Type of organization of the movement of production processes over time. Moscow State University of Printing Arts

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Organization of the production process over time

Concept and structure of the production cycle

The organization of the production process in time is a way of combining in time the main, auxiliary and service processes for processing the “input” of the organization into its “output”. The most important parameter of the organization of the production process in time is the production cycle of manufacturing an object of labor, providing a service or performing work from preparatory operations to final ones.

One of the most important tasks when constructing a production process over time is to achieve the minimum possible duration of the production cycle.

The production cycle (PC) is the period of time from the moment a product is launched into production until the moment it is completely manufactured, packaged, accepted and delivered to the warehouse. The production cycle is one of the most important indicators of the efficiency of the organization of main and auxiliary processes, affecting the production capacity and production program of the enterprise, the productivity of workers, the amount of working capital and other technical and economic indicators.

The main characteristics of the production cycle are its duration and structure. The duration of the production cycle is one of the most important characteristics of the level of organization of the production process. The production cycle for manufacturing a batch of parts is considered to be the time from the receipt of material into production until the completion of the manufacture of parts.

The production cycle duration indicator is widely used in in-plant planning: when justifying the size of the production program of an enterprise, workshop, or site; in the process of developing a calendar schedule for the movement of objects of labor; in the production process; when calculating the size of work in progress and the amount of working capital.

The duration of the production cycle for manufacturing products is the calendar period of time during which raw materials, basic materials, semi-finished products and components are transformed into finished products. The duration of the production cycle is expressed in calendar days or hours (if the labor intensity of manufacturing products is low).

Rice. 1. Structure of the production cycle.

The production cycle of any product includes:

1. The time spent on performing all technological operations for the manufacture of a product (technological cycle).

Technological operations are operations that result in changes in the appearance and internal content of objects of labor, as well as preparatory and final operations. Their duration depends on the type of production, its technical equipment, the progressiveness of technology, techniques and methods of work and other factors. The time required to complete technological operations is a technological cycle. The time it takes to complete one operation, during which one part is manufactured, is called the operating cycle.

2. Time to perform non-technological operations, i.e. time for transporting parts and assemblies, for recording and storing products, for monitoring product quality, etc.

3. The time of natural processes, if they are provided for by the technological process, when the labor process is absent, but the subject of labor changes, for example, cooling of parts in molds, drying of painted parts.

4. Break time is the time during which there is no impact on the subject of labor and there is no change in its quality characteristics, the product is not yet finished and the production process is not completed.

There are regulated and unregulated breaks. In turn, unregulated breaks, depending on the reasons that caused them, are classified into inter-operational (intra-shift), inter-shop and inter-shift (related to the operating mode). Interoperational breaks are divided into partition and waiting breaks.

Breaks in batching occur when parts are processed in batches: each part or unit, arriving at the workplace as part of a batch, lies twice: before the start and at the end of processing, until the entire batch goes through this operation

Waiting breaks are caused by inconsistency (non-synchronization) in the duration of adjacent operations of a technological process and occur when the previous operation ends before the workplace is freed up to perform the next operation.

Inter-shop breaks are due to the fact that the completion dates for the production of component parts of assembly units in different shops are different and the parts lie waiting for completeness. Completion interruptions occur in cases where parts and assemblies lie idle due to the incomplete production of other parts included in one set.

Inter-shift breaks are determined by the operating mode (number and duration of shifts) and include breaks between work shifts, weekends and holidays, lunch breaks, and rest breaks for workers.

Unregulated breaks are associated with downtime of equipment and workers for various organizational and technical reasons not provided for by the operating mode (lack of raw materials, equipment breakdown, absenteeism of workers, etc.) and are included in the production cycle in the form of a correction factor or are not taken into account.

In general, the duration of the production cycle of a batch of parts (D pc) is determined by the formula:

T pc = (T pz + T tech + T eat + T vsp + T per) - T sov, where

T pz - preparatory and final time, hour; T tech is the time of the technological cycle with a sequential type of movement of objects of labor, h; T eats - the time of natural processes. h; T ss - time of auxiliary operations, h, T per - time of organizational and technical breaks, h; T owls is the time of combined operations.

The ratio of time spent on various types of work and breaks in the production process is called the structure of the production cycle, which is determined by the nature of the product being manufactured, the features of the technological process of its production, and the type of production. Therefore, the structure of the production cycle is not the same at enterprises in different industries. Thus, in enterprises with a continuous production process (metallurgical plants), the working part of the cycle has the greatest share. At enterprises with a batch method of organizing production (mechanical engineering), the largest share of time in the production cycle is taken by breaks for various reasons, which often amount to 60-80% of the duration of the production cycle.

The duration of the structural components of the production cycle also depends on design-technological and organizational-economic factors.

The complexity of the design, dimensions, and weight of the product determine the number of production processes used, their relationships, the total labor intensity of the work, and therefore the duration of the production cycle. The duration of the production cycle depends on the equipment of the technical process with various types of tools and devices, which affects the processing time or assembly of the product.

Organizational and economic factors are associated with methods of labor movement in the production process (sequential or parallel), with the level of organization of workplaces (whether it is convenient for a worker to carry out labor movements), with material incentive systems (forms of remuneration and bonus indicators). Organizational and economic conditions have a decisive influence on the duration of auxiliary operations, service processes, as well as on the duration of various types of interruptions in the movement of objects of labor.

The economic significance of reducing the duration of the production cycle lies in the fact that its duration determines the size of work in progress, the cost of which is one of the most significant parts of the enterprise's working capital. So. at mechanical engineering enterprises with a relatively long production cycle, work in progress makes up 30-50% of working capital in the inventories of enterprises. At enterprises where the duration of the production cycle is especially long (shipbuilding plants, factories for the production of powerful energy equipment, etc.) , 60-80% of working capital is in work in progress.

Reducing the duration of the production cycle leads to a decrease in the need for working capital, since the longer the duration of the production cycle, the more working capital the enterprise requires, the longer the period of their turnover, the longer they are “dead” in production, i.e. remain motionless.

Reducing the duration of the production cycle leads to a reduction in the required warehouse space for storing work in progress, stocks of raw materials and materials, to improving the use of fixed assets, and reducing production costs

Calculation of production cycle duration

When determining the duration of a production cycle, the duration of its three components is usually calculated: the duration of the technological part of the cycle, the time of breaks for various reasons and the time of natural breaks, if they are provided for by the technological process. The remaining elements of the duration of the production cycle either have an insignificant value, for example, preparatory and final time, or they are carried out during breaks for various reasons, for example, time for carrying out transport operations, time for accounting and packaging of products.

The duration of the operational cycle for processing a batch of parts in one operation T o is determined by the formula:

where n is the number of parts in the batch, t is the processing time of one part, min, c is the number of workstations at which this operation is performed.

Factors influencing the duration of the technological cycle:

· labor intensity of the operations performed;

· standards for the duration of cycle elements, regulated breaks;

· a method of transferring batches of processed parts from operation to operation, from one workplace to the next, i.e. on the type of movement of objects of labor in the production process.

To construct a schedule for the movement of a batch of products according to operations for various types of movement, we determine the duration of the operational cycle for processing a batch of parts for various types of movement.

There are three main types of movement of objects of labor: sequential, parallel and parallel-sequential or mixed (see Fig. 2).

Rice. 2.Schedule of movement of objects of labor.

The sequential type of movement of objects of labor in the production process is characterized by the fact that when producing a batch of parts in a multi-operational technological process, it is transferred to each subsequent operation (workplace) only after the processing of all parts in the previous operation is completed. Parallelism here is allowed only when performing an operation of the same name on several workstations.

The duration of the technological cycle T c with a sequential method of combining operations is proportional to the size of the batch and the labor intensity of the operations and is determined by the formula:

where i is the index of operations; t i is the complexity of processing one item of labor in the i-th operation; n - number of parts in the batch, pcs.

The disadvantage of sequential movement is the long duration of the operating cycle. Each part waits for the entire batch to be processed before starting the next operation, resulting in a longer overall cycle. However, sequential motion is distinguished by its simplicity of organization and is widely used in single and mass production for batch processing of parts and assembly of components.

Example. Let us assume that it is necessary to process a batch of parts (P d) in the amount of 20 pieces, the number of operations is 4: the first operation lasts (t 1) - 0.5 minutes; second (t 2) - 2 min; third (t 3) - 1 min; fourth (t 4) - 3 min. The number of jobs at each operation is one. The fourth operation is performed at two workstations (C). Under these conditions, the duration of the technological cycle (T c.seq) in a sequential form will be:

T c.seq = 20 * (0.5 / 1+ 2 /1 +1 / 1 +3 / 2) = 100 min.

To reduce the duration of the production cycle, it is possible to transfer objects of labor (parts) from one operation to another in parts (transport, transfer batches). This transfer of objects of labor occurs with a parallel type of movement of labor in the production process.

The parallel type of movement is characterized by the fact that a batch of processed parts is divided into a number of transport batches. The first transport batch is launched into production at the first operation of the production process, and after processing is completed, it is immediately transferred to the second and subsequent operations, without waiting for the completion of processing of the entire batch of parts in the first and subsequent operations. In this case, it is necessary to ensure the continuity of processing of a batch of parts only for the most labor-intensive operation; in our calculation example, this is the second operation. The continuity of processing of parts of other transport batches for the first and the rest (in our example, these are the third and fourth operations) is not ensured.

The second transport batch is put into production for the first operation of the production process in such a way that the completion time of its processing in the first operation coincides with the completion time of processing of the first transport batch in the second operation, which in the accepted condition is the most labor-intensive. After processing in the second operation is completed, the second transport batch is transferred for processing to the third and subsequent operations (a sequential type of movement of parts in the production process is used). The same procedure for launching the third and fourth transport batches into the first operation.

The duration of the production cycle with a parallel method of combining operations is determined by the formula:

where p is the processing batch size; t main - time of execution of the longest (main) operation of the technological process.

With parallel movement compared to sequential movement, the duration of the operating cycle is significantly reduced. However, if during parallel movement the operations are not equal and not multiple in duration, i.e. are not synchronized, then in all operations, with the exception of the operation with the maximum duration, interruptions occur in the operation of equipment and workers. Complete elimination of such interruptions is achieved provided that operations are synchronized when:

Parallel motion is used in mass and large-scale production when performing operations of equal or multiple durations.

Based on the accepted conditions, the duration of the technological cycle with a parallel type of movement of objects of labor (T c.parall) in the example will be:

Tc.paral = 0.5·5+2·20+1·5+3/2·5=55 (min).

With a parallel type of movement of objects of labor, the duration of the technological cycle is sharply reduced compared to the sequential type of movement. Under the accepted condition, the duration of the technological cycle was reduced from 100 minutes to 55 (almost twice).

However, the parallel type of movement causes equipment downtime at workplaces where the duration of the operation is less than the most labor-intensive operation. These downtimes are greater, the greater the difference between the execution time of the longest (main) operation and the time spent on other operations. In this regard, a parallel type of movement is justified in the case when the time of various operations is approximately equal to or a multiple of each other, i.e. in conditions of continuous flow production.

The parallel-sequential type of movement of objects of labor is characterized by the fact that the entire batch of parts is not divided into transport (transfer) batches, but is put into production for the first operation and processed continuously. The execution of the subsequent operation (second) begins before the completion of processing of the entire batch of parts in the previous operation (first). With this type of movement of objects of labor, adjacent operations overlap in time due to the fact that they are carried out in parallel for some time.

With a parallel-sequential type of movement of objects of labor, the amount of overlapping time between two adjacent operations is determined, which is equal to the time for processing the entire batch of parts put into production, minus the processing time of one transport batch - according to the duration of the short operation between two adjacent ones.

The duration of the production cycle with a parallel-sequential method of combining operations is determined by the formula:

where is the time combination of two adjacent operations, min.

The combination S is determined by the formula (p=1):

where t min is the execution time of the shorter operation of two adjacent ones, min.

The duration of parallel execution of two adjacent operations (combination time) depends on the time shift of the beginning of the subsequent operation compared to the previous one. There are two possible cases here:

1) the duration of the subsequent operation is greater than or equal to the previous one (taking into account the number of backup jobs):

2) the duration of subsequent operations is less than the previous one:

In the first case, the part, after being processed in the previous operation, immediately goes into processing for the subsequent operation. By the time this part is processed in the second operation, another part will arrive from the first operation, etc. Thus, processing in the subsequent operation occurs without equipment downtime, which is the condition for the parallel-sequential movement of parts. The time for parallel execution of these operations will be:

In the second case, continuous work on the subsequent operation requires a certain accumulation of parts, which is associated with a greater shift in its start time than in the first case. The time for parallel execution of operations is equal to:

As we can see, in both cases, the time for parallel execution of related operations is equal to the number of parts in a batch without one, multiplied by the duration of the smaller operation. If the last operation is denoted by, then in the general case for any pair of adjacent operations:

For m - operations of such combinations there will be m-1. And then, finally, we can write:

Under the accepted condition, the overlap time between the first and second operations will be:

S 1 =0.5 · (20 - 1) = 9.5 min.

Between the first and second operations, the short operation is considered to be the first one, lasting 0.5 minutes.

We determine the overlap time between other related operations:

S 2 =1·(20-1)= 19 min.

S 3 =1·(20-1)= 19 min.

Between the second and third, between the third and fourth operations, the same third operation, lasting 1.0 minutes, is considered short, therefore it is taken into account in calculating the amount of overlapped time.

The amount of overlapped time will be:

9.5+ 19+19 = 47.5 (min).

The duration of the technological cycle with a parallel-sequential type of movement will be:

T c.p.p. =100 - 47.5=52.5 (min).

The parallel-sequential type of movement of objects of labor eliminates the disadvantages of the sequential type, where the production cycle takes a long time, performing short operations when processing a batch of parts. However, a mixed type of movement requires careful organization of the production process over time, since it is necessary to constantly maintain at the calculated level minimal, but sufficiently reliable reserves of objects of labor (parts) between operations to ensure uninterrupted operation of adjacent workplaces

Analysis of the characteristics of the types of movement of objects of labor allows us to draw the following conclusions:

firstly, the level of parallelism, continuity and the size of the technological cycle significantly depend on the type of movement of objects of labor in the production process;

secondly, in the presence of unsynchronized operations, all types of movement of objects of labor do not provide a minimum duration of the technological cycle, and therefore have large reserves of rationality;

thirdly, increasing the size of the batch of processed parts is especially advisable when there is a parallel type of movement of objects of labor, since in this case the technological cycle increases more slowly than the batch size;

fourthly, changes in time standards for operations significantly affect the duration of the technological cycle, however, this influence is economically contradictory for various types of movement of a batch of parts. So. Reducing the labor intensity of short operations with parallel-sequential movement of objects of labor increases labor productivity (output) in these operations, but at the same time causes production losses due to the lengthening of the technological cycle due to the increase in the storage of parts at workplaces where the labor intensity of operations is higher .

All types of movement of objects of labor do not take into account the duration of various types of breaks that occur in production. Breaks can be divided into groups: inter-operational (intra-cycle), inter-cycle breaks due to incompleteness of work in progress, breaks due to delays in completing part of the auxiliary operations and routine breaks. Interoperational breaks include breaks due to batching and breaks due to the serial loading of equipment, the so-called waiting breaks.

Breaks due to batching are due to the very nature of working in batches of parts. Each part, arriving at the workplace as part of a batch, lies twice, once before the start of processing, waiting for the turn to arrive, and another time - after the end of processing, waiting for the end of processing of the last part in the batch. For example, processing of a batch of 100 parts on a lathe begins; the labor intensity of processing the part is 5 minutes. The eighth part waited for processing to begin (sat) for 35 minutes (7 years * 5 minutes). After completing the operation, the eighth part will wait for the completion of processing of the last, hundredth part for 460 minutes (5 minutes * 92 parts).

Interruptions due to the serial loading of equipment when processing a batch of parts occur in cases where their processing is completed at one workplace and the parts are transported to another workplace for further processing. However, this workplace is currently occupied by the processing of a batch of parts for another serial product. For example, after processing on a lathe, the batch is transported to the milling workplace. However, the milling machine is busy processing a batch of 200 parts for another product. In this case, the hundredth part is being processed and the operation duration is 4 minutes. The delivered batch of parts will lie at the milling machine for 400 minutes.

The average value of interoperational delay is determined empirically and varies within significant limits. This value depends on the number of operations performed at the workplace, i.e. on its seriality coefficient (level of specialization).

Interruptions due to incompleteness of work in progress occur with a complex-assembly planning system, when finished parts and assemblies lie idle due to the lack of other blanks and parts included together with the first ones in one set.

Poor organization of workplaces, untimely supply of materials and tools, poor quality of technical documentation or delays in its preparation, deficiencies in repairs - all this can lead to forced breaks, and, consequently, to an increase in the duration of the production cycle. Regular breaks are regulated by the operating mode of the enterprise (lunch breaks, between shifts, non-working shifts, non-working days). These breaks will be the smallest in a continuous work week. Breaks associated with the operating mode of the enterprise are usually taken into account by converting the production cycle, calculated based on working hours, into calendar time, while maintaining the proportionality of all components of the cycle.

It must be borne in mind that the duration of the production cycle of the entire product is not the arithmetic sum of the cycle times for manufacturing parts and assemblies, since many of them are processed or assembled simultaneously, in other words, in parallel.

Ways to reduce production cycle time

One of the urgent tasks of all enterprise services is the development of measures related to reducing the duration of the production cycle. The reduction must be carried out simultaneously in two directions: reducing the working period of the cycle and completely eliminating or minimizing various breaks. The weight of practical measures to reduce the duration of the production cycle follows from the principles of constructing the production process, primarily from the principles of proportionality, parallelism and continuity. There are two main directions for reducing the duration of the production cycle

Technological progress causes a reduction in the duration of the production process as a result of the introduction of more modern technological processes; completely eliminating some operations or replacing some with others that are more productive; intensification of the duration of the production process.

The duration of natural carding is significantly reduced as a result of replacing them with appropriate technological operations.

Reducing labor intensity can be achieved by changing the starting materials. Reducing preparatory and final time is achieved by introducing the flow method of organizing production, standard and universal devices. Reducing the duration of quality control of performed operations is achieved by their mechanization and automation, combining the time for performing technological and control operations.

Technical progress is expressed in increasing the manufacturability of the design, which is manifested in the maximum approximation of the design to the requirements of the technological process.

Improving the organization of production often has a decisive influence on the duration of the production cycle, since the amount of interoperational breaks in enterprises with batch or single methods of organizing production can be several times greater than the duration of the technological cycle. The main ways to improve the organization of labor and production include:

rational layout of workplaces, in accordance with the sequence of technological operations and improving the organization of the transfer of parts from operation to operation within a site or workshop;

reducing the time of interruptions caused by equipment failures, which requires a clear organization of scheduled preventive maintenance of equipment;

3. acceleration of auxiliary processes through their extensive mechanization and automation, due to which they are not only completed faster, but also increase the reliability of servicing the main processes;

improving the work of the transport sector in order to organize uniform transport services for all workshops during all shifts by organizing circular flights, introducing a fixed schedule, transport operations, using counting containers, automatic scales, and introducing containers;

organizing a preparatory shift, during which equipment is set up, preparation for the production of materials, tools, devices,

introduction of daily shift planning and organization of work according to an hourly schedule;

improving the organization of production in service and auxiliary farms;

introduction of parallel and parallel-sequential methods of transferring parts in the production process;

determining the most rational procedure for launching a batch of products into production, which leads to a reduction in the time it takes for parts to sit at work stations;

organization of a flow production method, which is characterized by the complete absence of interoperational storage, in the case of complete synchronization of production operations, or a significant reduction in interoperational storage in conditions of partial synchronization of the operation, that is, on discontinuous production lines.

increasing the level of specialization of jobs, which makes it possible to eliminate or significantly reduce the waiting time for the release of jobs occupied by operations for the production of batches of parts for another serial product; at the same time, equipment changeovers are eliminated and thereby the preparatory and final time, which is an integral part of the working time of the cycle, is reduced.

The discovery of reserves for reducing the duration of the work cycle is facilitated by photographs of the working day of those employed in various stages of the work cycle, which will make it possible to determine the actual duration of the working time of the cycle and the time of breaks, both dependent and independent of the workers. To identify reserves for reducing the production rate, data from special observations or data from planning and accounting documentation can be used.

Measures to reduce the duration of the PC provide a comprehensive economic effect. They create the preconditions for improving the use of production capacity and reducing the share of overhead costs in the cost of a unit of production. Thus, reducing the duration of all elements of the PC is an important condition for improving many technical and economic indicators of the enterprise.

Bibliography:

1. Avrashkov L.Ya. Adamchuk V.V., Antonova O.V., et al. Enterprise Economics. - M., UNITI, 2001.

2. William J. Stevenson Production Management. - M., ZAO “Publishing House BINOM”, 2000.

3. Gruzinov V.P., Gribov V.D. Enterprise economy. Textbook.-M.:IEP, 2004.

4. Kalacheva A.P. Organization of enterprise work.-M.: PRIOR, 2000.- 431 p.

5. Sergeev I.V. Enterprise Economics: Textbook. allowance. - 2nd ed., revised. and additional - M.: Finance and Statistics, 2004. - 304 p.

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1 Organization of the production process in time and space Moscow State University of Transport (MIIT). Institute of Economics and Finance

2 The production cycle is a complex of basic, auxiliary and service processes organized in a certain way in time, necessary for the manufacture of a certain type of product. The duration of the production cycle is the calendar period of time during which a material, workpiece or other processed item goes through all the operations of the production process or a certain part of it and is transformed into a finished product. Moscow State Transport University (MIIT). Institute of Economics and Finance

3 The structure of the production cycle includes the time of the working period and the time of breaks. During the working period, the actual technological operations and preparatory and final work are carried out. The working period also includes the duration of control and transport operations and the time of natural processes. The duration of breaks is determined by the labor regime, inter-operational storage of parts and shortcomings in the organization of labor and production. Moscow State Transport University (MIIT). Institute of Economics and Finance

4 Inter-operational waiting time is determined by breaks in batching, waiting and picking. Batch breaks occur when products are manufactured in batches and are due to the fact that the processed products lie until the entire batch has gone through this operation. In this case, it is assumed that a production batch is a group of products of the same name and standard size, launched into production within a certain time during the same preparatory and final period. Moscow State Transport University (MIIT). Institute of Economics and Finance

5 Wait interruptions are caused by inconsistent durations of two adjacent process operations. Packing interruptions are caused by the need to wait for the time when all the blanks, parts or assembly units included in one set of products will be manufactured. Picking interruptions occur during the transition from one stage of the production process to another. Moscow State Transport University (MIIT). Institute of Economics and Finance

6 In general, the duration of the production cycle is expressed by the following formula: Tt = Tt + Tpz + Te + Tk + Ttr + Tmo + Tpr, where Tt is the time of technological operations; Тпз – time of preparatory and final work; Te is the time of natural processes; Tk – time of control operations; Тtr – time of transportation of objects of labor; TMO – time of interoperative bedtime (intra-shift breaks); Tpr – time of breaks due to work schedule. Moscow State Transport University (MIIT). Institute of Economics and Finance

7 The duration of technological operations and preparatory and final work together form the operating cycle. An operating cycle is the duration of a completed part of a technological process performed at one workplace. The production cycle of a part is called simple. The production cycle of an assembly unit or product is called complex. The cycle can be single-operational or multi-operational. Moscow State Transport University (MIIT). Institute of Economics and Finance

8 The cycle time of a multi-operation process depends on the method of transferring parts from operation to operation. There are the following types of movement of objects of labor in the process of their manufacture: sequential; parallel-serial. Moscow State Transport University (MIIT). Institute of Economics and Finance

9 Sequential The entire batch of parts, the type of movement is transferred to the subsequent operation of labor items after the processing of all parts in the previous operation is completed. Parallel type of movement of objects of labor Parts are transferred to the Parallel sequential type of movement of objects of labor Parts from an operation to the next operation by a transport batch immediately after finishing its processing in the previous operation. The operation is transferred in transport batches or individually. Moscow State Transport University (MIIT). Institute of Economics and Finance

10 Reducing the duration of the production cycle can be achieved by implementing constructive, technological and organizational measures. Constructive measures include: widespread use of standards; the use of functional-cost analysis, which simplifies structural elements and increases the manufacturability of the design; simplification of the designs of products and their elements, unification and standardization of assembly units and parts, increasing the level of blockiness of products, reducing the proportion of mechanical processing of parts. Moscow State Transport University (MIIT). Institute of Economics and Finance

11 Technological measures include: the use of advanced technological processes and advanced technological equipment; reducing the time of natural processes by replacing them with appropriate technological processes; mechanization and automation of control and transport and warehouse operations; reducing processing allowances and increasing the accuracy of parts manufacturing; reducing the duration of processing stages; mechanization and automation of operations, including auxiliary ones; introduction of multi-position tools and devices, universal adjustment devices. Moscow State Transport University (MIIT). Institute of Economics and Finance

12 Organizational measures include: increasing the degree of parallelism in the execution of production cycle operations (parallel production of parts, parallel assembly of assembly units); reducing the duration of breaks; computerization of production processes; increasing the share of technically justified time standards, maintenance standards, and material consumption standards. Moscow State Transport University (MIIT). Institute of Economics and Finance

13 The production structure of an enterprise is a set of production units of the enterprise that are part of it, as well as the forms of relationships between them. In modern conditions, the production process can be considered in two of its varieties: as a process of material production with the final result - commercial products; as a process of design production with the final result - a scientific and technical product. Moscow State Transport University (MIIT). Institute of Economics and Finance

14 The nature of the production structure of an enterprise depends on the types of its activities, the main ones of which are the following: research; production; research and production; production and technical; managerial and economic. The priority of relevant activities determines the structure of the enterprise. The composition of the divisions of an enterprise specializing in production activities is determined by the design features of the products produced and the technology of their manufacture, the scale of production, the specialization of the enterprise and the existing cooperative ties. Moscow State Transport University (MIIT). Institute of Economics and Finance

15 The production structure is developed taking into account the logistics goals of the enterprise and must meet the logistics requirements. The main ones are: the formation of production modules and ensuring their interaction within the framework of the production chain of manufacturing and marketing of products; structuring of storage systems; placement of equipment along the technological process towards its completion; minimization of production process stages (production process integration); use of technologically flexible equipment. Moscow State Transport University (MIIT). Institute of Economics and Finance

16 In modern conditions, the form of ownership has a great influence on the structure of the enterprise. In the Russian Federation, private, state, municipal and other forms of property are equally recognized and protected. Currently, various forms of organizations are widespread. There are small, medium and large enterprises, the production structure of each of them has corresponding features. Moscow State Transport University (MIIT). Institute of Economics and Finance

17 Federal Law of July 24, 2007 No. 209-FZ “On the development of small and medium-sized businesses in the Russian Federation”. Small and medium-sized businesses include legal entities; the average number of employees for the previous calendar year should not exceed the following limit values: from one hundred one to two hundred and fifty people inclusive for medium-sized enterprises; up to one hundred people inclusive for small enterprises; Among small enterprises, microenterprises stand out - up to fifteen people. Moscow State Transport University (MIIT). Institute of Economics and Finance

18 Decree of the Government of the Russian Federation dated July 22, 2008 No. 556 “On the maximum values ​​of revenue from the sale of goods (work, services) for each category of small and medium-sized businesses” established the maximum values ​​of revenue from the sale of goods (work, services) for the previous year without accounting for value added tax for the following categories of small and medium-sized businesses: micro-enterprises - 60 million rubles; small enterprises - 400 million rubles; medium enterprises - 1000 million rubles. Moscow State Transport University (MIIT). Institute of Economics and Finance

19 The structure of large and medium-sized enterprises includes workshops and production facilities. A workshop is the main structural unit of an enterprise, administratively separate and specializing in the production of certain parts and products, or in the performance of technologically homogeneous or identical-purpose work. The workshop includes production areas, which are a group of workplaces united according to certain characteristics. Moscow State Transport University (MIIT). Institute of Economics and Finance

20 The enterprises are divided into: Main workshops (procurement shop) processing shop (assembly shop) Auxiliary tool shop (repair and mechanical shop) power shop Servicing shops and facilities transport shop (warehouse) metrological service laboratories for various purposes The workshop includes production areas, as well as auxiliary and service units . Moscow State Transport University (MIIT). Institute of Economics and Finance

21 At large enterprises, divisions are formed in the production structure that unite a group of workshops and specialize in performing certain technological operations or manufacturing a group of parts and products. Such divisions were called production, and the structure of the enterprise was called multi-production. Moscow State Transport University (MIIT). Institute of Economics and Finance

22 The modern period of development of industrial production determines the need to facilitate the process of equipment changeover, speed up material flows, and reduce the time required for the development of new products. The solution to these problems is ensured by the use of new structural solutions: the use of a new type of production structure, called “cellular structure”; the formation in production of autonomous groups of highly qualified workers into a single team, who have a high degree of independence and are responsible for the areas of work assigned to them. Moscow State Transport University (MIIT). Institute of Economics and Finance

23 The organization of workshops and sections is based on the principles of concentration and specialization. Specialization of workshops and production areas can be carried out by type of work - technological specialization (for example, a foundry shop, a thermal shop or a galvanizing shop) or by type of manufactured products - subject specialization (for example, a body parts shop, a shaft section, a gearbox manufacturing shop). If a complete cycle of manufacturing a product or part is carried out within a workshop or site, this division is called subject-closed. Moscow State Transport University (MIIT). Institute of Economics and Finance

24 With technological specialization, high equipment utilization is ensured, high production flexibility is achieved when developing new products and changing production facilities. At the same time, operational production planning becomes more difficult, the production cycle is lengthened, and responsibility for product quality is reduced. The technological principle is recommended to be used in the following cases: when producing a large range of products; with their relatively low serial number; if it is impossible to balance equipment and labor; with a large number of control operations and a significant number of changeovers. Moscow State Transport University (MIIT). Institute of Economics and Finance

25 The use of subject specialization makes it possible to concentrate all work on the production of a product part within one workshop or area, and increases the responsibility of performers for the quality of products and the completion of tasks. Subject specialization creates the prerequisites for organizing continuous and automated production, ensures the implementation of the principle of direct flow, and simplifies planning and accounting. However, it is not always possible to achieve full equipment utilization; restructuring production to produce new products requires large expenses. Moscow State Transport University (MIIT). Institute of Economics and Finance

26 The subject principle is recommended to be applied in the following cases: when producing one or two standard products; with a large volume and a high degree of stability in the production of products; where possible, there is a good balance between equipment and manpower; with a minimum of control operations and a small number of changeovers. Moscow State Transport University (MIIT). Institute of Economics and Finance

27 Closed workshops and areas also have significant economic advantages, the organization of which makes it possible to reduce the duration of the production cycle for the manufacture of products as a result of the complete or partial elimination of counter or return movements, and to simplify the planning system and operational management of production progress. Moscow State Transport University (MIIT). Institute of Economics and Finance

28 Based on the production structure, a master plan for the enterprise is developed. The master plan is the spatial arrangement of all workshops and services, as well as transport routes and communications on the territory of the enterprise. Moscow State Transport University (MIIT). Institute of Economics and Finance

29 The master plan of the enterprise is developed taking into account the following basic principles: the requirements for the rational organization of production processes, the fullest use of the enterprise area and the use of advanced modes of transport are taken into account; the buildings of workshops and warehouses should be located along the technological process in order to ensure the shortest path for the movement of materials and finished products; buildings of auxiliary workshops should be located near the buildings of the main workshops, which have the largest amount of equipment; buildings are located in relation to the cardinal directions and wind rose in such a way as to provide the best conditions for lighting and ventilation. Moscow State Transport University (MIIT). Institute of Economics and Finance

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PRACTICAL LESSON

Organization of production processes over time

There are three types of movement of objects of labor in the process of their manufacture:

- consistent;

- parallel;

- series-parallel.

At sequential type of movement the entire production batch of parts is transferred to the subsequent operation after finishing processing of all parts in the previous operation.

Technological process for processing part A , The launch batch for which is assumed to be n = 9 pieces consists of five operations. The execution time of each operation is correspondingly equal to:

t1 = 2 min, t2 = 1 min, t3 = 4 min, t4 = 3 min, t5 = 1 min.

The total processing time for one part is 11 minutes.

The duration of the operational cycle for processing a batch of parts A in this case is the sum of the time spent by the entire batch of parts at each workplace.

In general, the cycle duration for the sequential movement of objects of labor is determined by the formula:

,

Where n- number of parts in the production batch;

m- number of operations in the technological process;

- lead time i- th operations;

- amount of equipment for i- th operations.

min

The movement diagram of a batch of parts A under given conditions and with a sequential form of organization of the production process is shown in Fig. 1.

Rice. 1. Movement of a batch of parts A with a sequential form of organization of the production process

The duration of the operational cycle for processing a batch of parts A in this case (as can be seen from the graph) is the sum of the time spent by the entire batch of parts at each workplace.

The sequential form of organizing the production process over time has its advantages and disadvantages.

Advantages:

- absence of interruptions in the operation of equipment and workers at each operation, the possibility of their high load during the shift;

-the number of accounting and planning units is small, because parties are not split up.

Flaws:

- long interoperational waiting times due to lack of parallelism in the processing of parts

Tmo = (n - 1) t pcs;

- large volume of work in progress;

- the longest cycle time due to the fact that with this form the parts lie longer than they are processed. This disadvantage is eliminated with a parallel form.

It is used for small batches and low labor intensity of work.

At parallel type of movement Each part from a production batch, after processing in the previous operation, is immediately transferred to the subsequent operation individually or in small parts according to p- pieces (the so-called transport or transfer batch). In our example p = 3.

The flow diagram of a batch of parts to work stations with this form is shown in Fig. 2.

From this diagram it follows that the duration of the operating cycle for the example we are considering can be presented in the form of three components: A, B, C. Each of these components, in turn, can be represented as follows:

Operating cycle component B here is nothing more than the processing time of a batch of parts without one transfer batch ( n- p) in the third operation, the execution time of which is the longest of all operations in the technological process of processing the part.

Summing up all the components of the cycle, we get:

In general, the cycle duration with a parallel type of movement of objects of labor is equal to:

- duration of the longest operation.

min

Advantages:

- the shortest cycle;

- clear rhythm of the production process and the absence of laying down parts in all operations except the first and last, when transferring parts piece by piece from operation to operation.

Disadvantage: the possibilities of using the method are limited, since a prerequisite for its implementation is equality or a multiple of the duration of operations. Otherwise, interruptions in the operation of equipment and workers (in all operations except the main one) are inevitable, which significantly impairs the efficiency of using the latter.

It is used in continuous production, in assembly, where it is easier to synchronize operations, i.e. align their duration with each other.

If the condition for complete synchronization of technological processes is not feasible, then in this case a parallel-sequential form of organization is rational.

Rice. 2. Movement of a batch of parts A with a parallel form of organization of the production process

At parallel-sequential type of movement parts are transferred from operation to operation in transport (transfer) batches. In this case, there is a partial overlap of the execution time of adjacent operations, and the entire batch is processed at each operation without interruptions. The production cycle is longer compared to a parallel one, but less than with the sequential movement of objects of labor.

The part processing diagram for the example we are considering is shown in Fig. 3. From this diagram it is clear that there are two possible combinations of adjacent operations in time.

The first option is when the execution time of the previous operation is less than the execution time of the subsequent operation. With this option, we begin constructing a diagram of the movement of parts to the next workplace by processing the first transfer batch of parts there.

The second option is when, on the contrary, the execution time of the previous operation of the technological process is longer than the execution time of the subsequent operation. With this option, we begin constructing a diagram of the movement of parts to the next workplace from the last transfer batch of parts.

From the diagram in Fig. 3 it can be seen that the duration of the production cycle for processing a batch of parts with the considered form of organization of the production process can be represented as the cycle duration with a sequential form minus the time of overlap of processing of the part at adjacent workplaces, i.e. How:

For the example we illustrate, the total overlap time is:

In turn, the overlap time can be represented as the processing time of a production batch of parts without one transfer batch p at the first workplace, i.e. How

Likewise:

Therefore, the total overlap time can be defined as

In general, the cycle duration for sequential-parallel movement of objects of labor is calculated by the formula:

In the example we are considering, the duration of the production cycle is:

Thus, the parallel-sequential form of organization of production processes combines the advantages of both sequential and parallel forms of organization of production processes over time. The serial-parallel type of movement of objects of labor is widely used in procurement, processing and assembly shops with significant labor intensity of products and large production batch sizes.

It should be noted that in conditions of single production the sequential form is predominant, in conditions of mass production - parallel, and in conditions of serial production - parallel-sequential.

Rice. 3. Scheme of movement of a batch of parts in a parallel-series form

Study of the influence of various factorsfor the duration of the production cycle

Work order

1. Production batch size

The size of the production batch plays a significant role in the cycle time of the production process. As the production batch increases, the cycle time also increases.

Production batches available in sizes of 10 pcs, 20 pcs, 30 pcs, 40 pcs, 50 pcs. and 70 pcs.

It is necessary to calculate the cycle time for three methods of transferring parts from operation to operation.

Draw a graph of the dependence of the cycle duration on the size of the production batch Tc (n).

Draw a conclusion.

Using formulas (1-3), cycle times were calculated for different production batch sizes. The calculation results are shown in Table 2.

Table 2 Results of cycle time calculations for various production batch sizes

Fig 4 - Graph of cycle time depending on the size of the production batch for various types of movement of objects of labor

The dependence graph for the sequential type of movement of objects of labor has a steeper slope, therefore, the cycle duration for this type of movement changes more rapidly.

With a parallel type of movement, the cycle duration will be minimal.

The durations of cycles for parallel and series-parallel types of movement differ slightly (for these conditions).

2. Transfer lot size

The size of the transfer lot plays an important role in cycle time. With a production batch of 20 pcs. the number of parts in a transfer batch can be: 1,2,4,5,10,20 pcs.

Draw a graph of the dependence of the cycle duration on the size of the transfer batch Tc (r).

Draw a conclusion.

The results of calculating the cycle duration using known formulas are presented in Table 3. Since there is no transfer batch in the sequential type of movement, we make calculations for series-parallel and parallel types of movement.

Table 3 Results of calculation of cycle duration for different transfer lot sizes

With a parallel type of movement, the cycle duration is less than with serial-parallel movement (all other things being equal).

If the size of the transfer batch coincides with the size of the production batch, then the cycle duration for parallel and serial-parallel types of movement will be equal and will be equal to the cycle duration for sequential movement.

Rice. 5 - Graph of cycle duration for different sizes of transfer batch and types of movement of objects of labor

The smaller the transfer lot size, the shorter the cycle time.

3. Number of jobs per operation

The cycle time of the production process also depends on the number of jobs. As the number of jobs increases, the cycle time decreases.

We change the number of jobs - 1,2,4,5,10,20, i.e. there are 5 operations: in the first case, there will be one workplace at each operation, then two, and so on up to twenty workplaces at each operation.

Construct a graph of the dependence of the cycle duration on the number of TC jobs ().

Draw a conclusion.

We assume the size of production and transfer batches to be the same as in the initial data of task No. 1.

Table 4 Results of calculation of cycle duration for different types of movement for different numbers of jobs

Movement type	number of jobs at each operation

Rice. 6 - Graphs of cycle time depending on the number of jobs at each operation

The more jobs are involved in performing an operation, the shorter the cycle time.

With an increase in the number of jobs, the cycle duration changes according to a power-law (nonlinear) dependence.

With a very large number of jobs, the difference between cycle times for different types of movement of objects of labor becomes insignificant.

4. Order of operations

There is a production batch of 9 pieces, a transfer batch of 3 pieces.

The complexity of each operation is different.

According to the initial data of problem No. 1 we have:

Table 5

Enter the transaction numbers in the first column:

a) according to increasing labor intensity;

b) in descending order of labor intensity;

c) we put the values ​​of maximum labor intensity in the middle,

d) we put the minimum labor intensity values ​​in the middle;

d) in order

e) enter in reverse order - 5;4;3;2;1

Based on the results obtained, we draw conclusions.

Table 7 Results of calculation of cycle duration for different order of execution of work operations

	Ascending	descending	maximum in the middle	minimum in the middle	By	in reverse order

As we see from Table 7, the order of operations does not affect the cycle duration for sequential and parallel types of movement of objects of labor. processing batch part production

The order of operations should be taken into account if the accepted type of movement of objects of labor is serial-parallel. Since the time of their combination depends on the order of operations (the short one is selected from two adjacent ones). The shortest cycle duration with a series-parallel type of movement is observed in cases where operations are arranged in increasing or decreasing labor intensity, and also when the most labor-intensive operation is in the middle.

Calculating cycle times for a simple manufacturing process

The production cycle for manufacturing a batch of parts takes into account not only the operational cycle, but also natural processes, breaks associated with the operating mode, and other components. In this case, the cycle for the considered types of movement is determined by the formula:

where Top is the duration of the operating cycle, calculated using one of the formulas (2), (3), (4), depending on the type of movement of objects of labor, hours;

Tcm - duration of one work shift, hours;

f is the number of shifts during which a given production batch is manufactured;

Te - duration of natural processes (taken from technological process maps), hours;

Tmo is the average inter-operational waiting time (determined based on statistical data for a specific production), h. ;

Tzakh - time of entry into other workshops (set according to actual data for a specific production), days. ;

Nper is the coefficient for converting working days into calendar days (1.4).

Initial data for practical task No. 3 are given in Table 8

The duration of the operating cycle is:

- with sequential movement of objects of labor:

min = 76.67 hours

- with parallel-serial:

min = 29.17 hours

min = 22.83 hours

The duration of interoperative treatment is 2 hours (according to the initial data).

The duration of natural processes is not indicated in the source data. There is also no data on the time of entry into other workshops. For this reason, we do not take these cycle components into account in the calculation.

The duration of the production cycle for manufacturing a batch of parts will be:

With a sequential type of movement of objects of labor:

With series-parallel type of movement:

With parallel type of movement:

Cycle duration is rounded to the nearest larger number. So, with a sequential type of movement of objects of labor, the duration of the production cycle will be 15 days, with a series-parallel type - 7 days. And with parallel 6 days.

The order completion time will be:

For a sequential type of movement of objects of labor

For series-parallel type of movement:

For parallel type of movement:

Let's show it on the graph (Fig. 4)

Fig. 7 - Lead time for an order for a batch of parts of 200 pieces for various types of movement of objects of labor

Determining the cycle time of a complex process

The production cycle of a product includes cycles of manufacturing parts, assembling components and finished products, and testing operations. In this case, it is generally accepted that various parts are manufactured simultaneously. Therefore, the production cycle of the product includes the cycle of the most labor-intensive (leading) part. The production cycle of a product can be calculated using the formula:

where T c.d- production cycle for the production of the leading part, calendar. days;

T c.b- production cycle of assembly and testing work, calendar. days

To calculate the cycle time of a complex software product, it is necessary to know the assembly composition of the product, as well as data on the assembly time of this product, the assembly of assembly units and the duration of parts manufacturing cycles.

A graphical method can be used to determine the cycle of a complex production process. For this purpose, a cyclic schedule is drawn up.

The production cycles of simple processes included in complex ones are pre-established. According to the cyclic schedule, the period of advance of some processes by others is analyzed and the total duration of the cycle of a complex process for the production of a product or batch of products is determined as the largest sum of cycles of interconnected simple processes and interoperational breaks.

The cyclogram is constructed in the reverse order of the technological process, i.e. construction and calculation are carried out from right to left at a given moment of release of the product (device).

On the graph from right to left on a time scale, cycles of partial processes are plotted, starting from testing and ending with the manufacture of parts.

When constructing a schedule, it is necessary to take into account the reserve time between sections and workshops. If parts in a workshop are manufactured on the same equipment, then they are shown sequentially on the graph.

The cycle duration of the entire product (device) is determined on the graph according to the longest chain.

The standard value Tc is the basis for determining the order and timing of the supply of parts and assembly units for product assembly, the basis for intra-shop planning and organizing control over the progress of assembly.

TC allows you to establish the amount of work in progress and the working capital associated with it.

Construct a cyclogram of a complex production process if the deadline for delivery of a batch of products to the finished goods warehouse is November 23.

The initial data are given in table. 9, 10.

Table 9

Duration of assembly production cycles

Table 10

The duration of interoperational delays during assembly operations, testing, and production is 1 day.

Assembly operations are performed sequentially.

Batch size - 30 products.

Parts are stored in an intermediate warehouse (when transferred from workshop to workshop) for 4 days.

Using the initial data, fill out table 11

Table 11 Duration of production of parts and assemblies

Time, days
Assembly units
Time, days

Fig. 8 - Scheme of a complex process

A cyclogram of a complex process is presented in Figure 9.

Rice. 9 - Cyclogram of a complex process

Let us determine the duration of a complex process analytically using formula (6):

The leading part is part D1, since it takes the most time to manufacture. This part is processed in workshop No. 1 for 15 days, and then in workshop No. 2 for 25 days. The part lies between workshops for 4 days. We get:

Tt.d = 15+4+25 = 44 days.

The production cycle of assembly work consists of 5 operations that are performed sequentially. 1 day is spent between assembly operations. Test work lasts 25 days and it takes 3 days to release the product. We get:

Tt.b = (1+2.5+10+0.5+0.5)+1 4+1+25+1+3 = 48.5 days

The total duration of the complex process is:

Tc = Tc.d + Tc.b = 44+48.5 = 92.5 days

It takes 92.5 days to produce one product. If finished products are to arrive at the warehouse on November 23, then production of the product must begin on August 21.

The production of 30 products will cost:

92.5 30 = 2775 days or 92.5 months or 7.7 years

Bibliography

1. Organization of production and enterprise management: textbook / O.G. Turovets et al. - M.: INFRA-M, 2003. - 528 p.

2. Theoretical foundations of production management: textbook. allowance / Yu.M. Soldak, F.I. Paramonov -M.: BINOM, Laboratory of Knowledge, 2003. -280 p.

3. Organization, planning and production management / N.I. Novitsky, V.P Pashuto -M.: Finance and Statistics, 2007 -575 p.

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The basis for organizing the production process over time is the production cycle.

Production cycle- time interval from the beginning to the end of production. This is the time during which objects of labor put into production are transformed into finished products. The time spent by objects of labor in the form of inventories is not included in the production cycle.

The time costs included in the production cycle are shown in Fig. 1.

Production time Tpr consists of the duration of technological operations Ttech, natural processes Test, auxiliary operations – preparatory and final Tp-z, transport Tt and control Tk.

Break times Tper is divided into breaks during working and non-working hours, the so-called regulated breaks.

Breaks during working hours consist of partition breaks Tpar and interoperational breaks Tmo and intershop T MC expectations.

Breaks in batching are associated with the processing of objects of labor in batches. Objects of labor in a batch are not processed simultaneously, but one or several pieces at a time. Each product waits its turn for processing, after which it waits for the entire batch to be processed. For example, if objects of labor are processed in batches of 20 pieces, then the first product is processed, 19 are waiting in line for processing. Then, after processing is completed, each product awaits the end of processing of the entire batch.

Waiting breaks occur when items of labor arriving at a workplace cannot be processed due to its busyness. Waiting breaks can be intra- and inter-shop.

Breaks during non-working hours are determined by the operating hours of the enterprise.

Figure 1 – Structure of the production cycle

The structure of the production cycle, i.e. the composition and ratio of the elements included in it, depends on the characteristics of the product, the technological processes of its manufacture, the type of production and a number of other factors.

In continuous production (metallurgical, chemical, etc.), the largest share in the production cycle is production time. In discontinuous (discrete) production, breaks often account for 70...75% of the total duration of the production cycle. As serial production increases, the proportion of breaks decreases.

There are simple production processes, consisting of a number of sequential operations without overlapping cycles, and complex ones, occurring with overlapping cycles.

The duration of a simple production cycle is generally calculated as the sum of its constituent elements:

Shopping center = Ttech + Tp-z + Tt + Tk + Test + Tper .

The time for carrying out control and transport work may partially or completely coincide with the time of breaks. The overlap time of individual elements of the production cycle is not included in its duration, so the duration of the cycle is usually less than the sum of all its components.

The basis of the production cycle is technological time, which, together with batch breaks, amounts to operating cycle.

The duration of the operating cycle depends on the number of items of labor in the batch being processed, the processing time of each, the number of workplaces at which this operation is performed, and on how the items of labor of the batch are transferred from operation to operation. There are three types of movement of batch products through technological process operations:

· consistent;

· parallel;

· parallel-serial.

Sequential The movement of objects of labor is characterized by the fact that a batch of objects of labor is transferred from operation to operation completely. Each subsequent operation begins only after the processing of the entire batch in the previous operation is completed (Fig. 2, a).

Figure 2 – Movement of objects of labor through technological process operations

The duration of the operating cycle is:

Then the last = n ´ å t,

Where n– the number of items of labor in the batch;

å t- the standard time for performing all operations with each object of labor.

The disadvantage of sequential movement is the long duration of the operating cycle. The advantage is ease of organization.

Parallel type of movement is characterized by the fact that objects of labor are transferred to a subsequent operation and processed immediately after the previous operation is completed, regardless of the readiness of the entire batch. At the same time, the duration of the operating cycle is significantly reduced, but it is difficult to achieve synchronization in the execution of operations, resulting in interruptions in the operation of equipment and workers (Fig. 2, b). The duration of the operating cycle in this case is equal to:

That's steam = å t + (n- 1 tmax,

Where tmax– time of execution of the longest operation.

Parallel-serial (mixed) movement is characterized by the fact that the processing of objects of labor in the subsequent operation begins before the end of processing of the entire batch in the previous operation, i.e. there is some parallelism in the execution of operations. In this case, the condition is set that the batch is continuously processed at each workplace. (Fig. 2, c). The duration of the operating cycle in this case is calculated as follows:

That's steam = å t + (n- 1) ´ (å td - å tk),

where å td– time of a long operation;

å tk– short operation time.

That's steam < That's steam < Then the last.

Having calculated the duration of the operating cycle, we begin to determine other components of the production cycle.

The duration of natural processes is taken according to the minimum time for their implementation in accordance with the requirements of technology.

The control or transportation time is usually overlapped by the inter-operational waiting time or is taken based on experimental data, taking into account measures to improve control and inter-operational transportation methods.

Interoperational breaks are calculated using various methods: experimental, statistical, graphical, analytical.

Intershop breaks are determined based on experimental data, based on specific production conditions and the adopted operational planning system.

The duration of complex production processes is determined mainly by a graphical method and is equal to the largest sum of cycles of sequentially interconnected simple processes and inter-cycle breaks.

The duration of the production cycle is an important indicator of the level of organization of the production process and has a significant impact on the economics of production.

Reducing the duration of the production cycle reduces the need for working capital employed in work in progress, ensures more complete use of equipment, and increases the production capacity of sections, workshops and the enterprise as a whole.

The duration of the production cycle is reduced in two ways:

· reduction of working period;

· minimizing various interruptions.

The most significant reserves for reducing the duration of the production cycle are:

1 – use of the most efficient technological processes;

2 – increasing the level of mechanization and automation of technological processes;

3 – rationalization of auxiliary work (transport, control, preparatory and final work, etc.).

Organization of the production process over time is a way of combining in time the main, auxiliary and servicing processes for processing the organization’s “input” into its “output”.

The most important parameter of the organization of the production process in time is the production cycle of manufacturing an object of labor, providing a service or performing work from preparatory operations to final ones.

The duration of the production cycle consists of working time and break time. The working period for manufacturing an object of labor consists of the time of technological operations, transport and warehouse operations and control operations. In turn, the time of technological operations consists of preparatory and final time and piece time.

Preparatory-final time is spent at the beginning of the work shift on preparing the workplace, debugging equipment, fixtures, installing tools, and at the end of the work shift on removing fixtures, tools, etc. This time is spent on a batch of items of labor processed during a shift.

Breaks during working hours are divided into natural processes (drying, normalization after heat treatment and other operations that occur without human intervention), organizational breaks (waiting for a workplace to become free, delay in the delivery of components, etc.), regulated breaks (lunch breaks, rest, etc.).

The duration of the production cycle for manufacturing a product as a whole is calculated after constructing a schedule for the complex process of assembling a product and calculating the duration of production cycles for manufacturing piece parts or their batches. This work is performed by technologists.

For example, the duration of the production cycle for the manufacture of a batch of parts of the same name is determined as the sum of all operations of preparatory and final time, piece time (this takes into account the simultaneous execution of the same operation at several workplaces, the parallel execution of all operations, the planned coefficient of overfulfillment of production standards), time of natural processes, transportation, quality control, breaks.

The main factors for reducing the duration of production processes are:

Simplification of the kinematic diagram of the product, increasing the level of blockiness for products of large-scale and mass production. “Simplicity of design is a measure of the designer’s intelligence.”

Simplification and improvement of technological processes for manufacturing products;

Unification and standardization of the component parts of the product, its structural elements, elements of technological processes, equipment, tooling, production organization;

Deepening detailed, technological and functional specialization based on unification and increase in the production program of products and its components;

Reducing the specific gravity of machined parts;

Analysis of compliance with the principles of rational organization of production processes: proportionality, parallelism, continuity, straightness, rhythm, etc.;

Mechanization and automation of time recording, control and transport and warehouse operations;

Reducing the time of natural processes by replacing them with appropriate technological processes;

Reducing inter-operational breaks;

Increasing the share of technically sound time standards, service standards, and resource consumption standards. Encouraging time savings and meeting quality requirements.

The organization of production processes over time is based on an analysis of compliance with the principles proportionality, continuity, parallelism, straightness, rhythm, etc..

1. Proportionality- a principle, the implementation of which ensures equal throughput of different workplaces of the same process, proportional provision of workplaces with information, material resources, personnel, etc.

Let's look at an example. The initial capacity of workplaces for the production of a batch of parts from four operations was as follows (Fig. 1.4.1).

M 1 = 0 M 2 = 15 M 3 = 6 M 4 = 10 pcs./shift

Rice. 1.41.. The production process for manufacturing parts consists of four operations:

1, 2, 3 and 4 - workplaces;

M 1, M 2, M 3 and M 4 - the corresponding capacity of workplaces (parts per month).

The throughput (power) M of the technological chain was 6 parts per shift. Moreover, the 3rd workplace is the bottleneck.

The power of the 2nd workplace is used at 6 x 100% / 15 = 40%, the power of the 1st and 4th workplaces is used at 6 x 100% / 10 = 60%

What needs to be done to improve the proportionality of the process?

There are four directions:

1. revision of the part design in order to ensure proportionality of operations in terms of labor intensity;

2. revision of the technological process, processing modes;

3. development and implementation of organizational measures to replace equipment and redevelop the site;

The need for these parts is 10 pcs. per shift.

In this example, another machine with the same productivity needs to be installed at the 3rd workplace. Then its capacity will be 12 pcs. per shift. For 2 units (about 80 minutes) this workplace will need to be loaded with another part, the 2nd workplace will need to be loaded by 30%.

If similar parts are found for additional loading of the 2nd and 3rd workplaces, then the power line will meet the proportionality requirements.

The principle of proportionality should be remembered when resolving any issues, since “the speed of the squadron is determined by the speed of the slowest ship.”

Proportionality is determined by formula 1.4.1:

np = A min/Amax, (1.4.1)

where: A min is the minimum throughput, or parameter of the workplace in the technological chain (for example, power, type of work, volume and quality of information, etc.);

Amax - maximum throughput.

Let us give an example of assessing the proportionality of the technological chain by type of work (Table 1.4.1).

Table 1.4.1

Example of proportionality assessment

Name	Job categories
Type of work
Worker grade

Analysis of the table data shows that in the first workplace the worker’s grade is lower than the required grade of work in technology, which means there is a high probability of defects. In the third workplace, on the contrary, work of the third category is performed by a worker of the fourth, which means that there is an overexpenditure of wages, since the worker must be paid according to his category. And at the last workplace, often the most responsible one, the finishing work of the fifth category is performed by a third-class worker. Saving on wages is fraught with the possibility of marriage.

According to actual data, the proportionality of the technological chain at the narrowest 4th place is equal to: 3 x 100/5 = 60%. This means that it is necessary to implement organizational measures to ensure compliance between job categories and workers.

2. Continuity- the principle of rational organization of processes, determined by the ratio of working time to the total duration of the process according to formula 1.4.2.

N = T slave / T c, (1.4..2)

where: T work - duration of working hours;

Gc - the total duration of the process, including downtime or keeping the object of labor between workplaces, at workplaces, etc.

3. Parallelism- the principle of rational organization of processes, characterizing the degree of combination of operations over time.

Types of combinations of operations: sequential, parallel and parallel-sequential (Fig. 1.4.3).

V = T steam / T last

4. Straightness- the principle of rational organization of processes, characterizing the optimal path of passage of the subject of labor, information, etc.

It is recommended to determine the straightness coefficient using formula (1.4.4).

5. Rhythm- the principle of rational organization of processes, characterizing the uniformity of their implementation over time.

K = EK g A / EK "", (1.4.5)

rhythm f 1 p’ 4 7

where Vf is the actual volume of work performed for the analyzed period (decade, month, quarter) within the plan (above the plan is not taken into account);

V" n - planned volume of work.

Let's give an example of rhythmicity assessment (Table 1.4.2).

The rhythmicity coefficient is equal to:

* rhythm = (5 + 10 + 20)/(20 + 20 + 20) = 35/60 = 0.58.

Table 14.2

Rhythmicity assessment (million rubles)

Analysis of the table data shows that, although the plan was exceeded by 8% in a month, the team worked poorly, 84% of the plan was done in the last ten days, there were storming and defects in work.

One of the ways to improve the listed indicators of the rational organization of production and management processes is increased process repeatability and operations.

In turn, a method for increasing the repeatability of processes is unification and typification of diverse partial processes.

The benefits of increasing process repeatability stem from the fact that the end results in mass production are better than in single production.

The listed principles of rational organization of processes are the main factor in increasing the organization of the management system, which is characterized by the degree of quantitative certainty of connections (entropy) between the components of the system. To reduce uncertainty, it is necessary to clearly record in all management documents (plans, programs, assignments, standards, regulations, instructions, etc.) the connections between management bodies and managed objects. Connections in the management system are established after constructing a tree of goals up to level IV and translating qualitative requirements into quantitative ones. To improve the clarity of coordination work, it is recommended to use network management methods.

CONTROL QUESTIONS

1. How can we explain the need to comply with the 22 principles of process rationalization?

2. Why is it necessary to ensure the innovative nature of the organization’s development?

3. How is compliance with the principle of quality-oriented processes ensured?

4. What is the essence of the principle of process adaptability?

5. What is process centralization?

6. What is the rational relationship between the motives of personnel management?

7. Why is it necessary to rank management objects?

8. How is process responsiveness ensured?

9. What is process regulation?

10. In what ways is the proportionality of processes achieved?

11. Why is it necessary to analyze the straightness of structures and processes?

12. How is process parallelism ensured?

13. What is rhythm?

14. What is the production process?

15. How does an object of labor differ from a tool?

16. What types of production processes do you know?

17. What are the relationships between different types of processes?

18. Why is it recommended to divide the main production process into preparatory, transformative and final?

19. What is the production process in space?

20. What is the production process in time?

21. What will be the score at the output of the system if its input is “five” and the process is “four”?

22. How can you “connect” organizational and production structures? Why is this necessary?