A device for checking a fire pump for leaks. Centrifugal pump test

Operation and maintenance of fire truck pumps is carried out in accordance with the “Manual for the Operation of Firefighting Equipment”, manufacturer’s instructions for fire trucks, fire pump certificates and other regulatory documents. centrifugal fire pump

When receiving fire trucks, it is necessary to check the integrity of the seals on the pump compartment. Before deployment to a combat crew, it is necessary to run-in the pumps when operating on open water sources. The geometric suction height when running pumps should not exceed 1.5 m. The suction line should be laid on two hoses with a suction mesh. Two pressure hose lines with a diameter of 66 mm should be laid from the pump, each for one hose 20 m long. Water is supplied through RS-70 trunks with a nozzle diameter of 19 mm.

When running in, the pressure on the pump must be maintained at no more than 50 m. The pump is run in for 10 hours. When running in pumps and installing them on fire reservoirs, it is not allowed to direct the barrels and jets of water into the reservoir. Otherwise, small bubbles form in the water, which enter the pump through the mesh and suction line and thereby contribute to the occurrence of cavitation. In addition, the pump parameters (pressure and flow), even without cavitation, will be lower than under normal operating conditions.

Run-in of pumps after a major overhaul is also carried out within 10 hours and in the same mode, after a routine repair - within 5 hours. During the run-in, it is necessary to monitor the readings of instruments (tachometer, pressure gauge, vacuum gauge) and the temperature of the pump housing at the location where the bearings are installed. and seals. After every 1 hour of pump operation, it is necessary to turn the oiler 2...3 turns to lubricate the seals. Before running in, the oiler must be filled with a special lubricant, and transmission oil must be poured into the space between the front and rear bearings.

The purpose of running-in is not only to break in the parts and elements of the transmission and fire pump, but also to check the functionality of the pump. If minor faults are found during running-in, they should be eliminated, and then further running-in should be carried out.

If defects are discovered during running-in or during the warranty period, it is necessary to draw up a complaint report and present it to the fire truck supplier. The procedure for submitting a complaint report to the supplier plant is set out in the “Manual on the operation of fire fighting equipment”. Before drawing up a complaint report for a major defect, you must call a representative of the supplier plant by telegram.

If a representative of the plant does not arrive within three days or notifies by telegram that it is impossible to arrive, a unilateral complaint report is drawn up with the participation of a specialist from a disinterested party. It is prohibited to disassemble the pump or other components in which a defect is found until a representative of the plant arrives or the plant receives a complaint report. The warranty period for fire truck pumps in accordance with OST 22-929-76 is 18 months from the date of receipt. The operating life of the PN-40UA pump before the first major overhaul according to the passport is 950 hours.

The running-in of pumps should end with testing them for pressure and flow at the rated speed of the pump shaft. It is convenient to carry out the test on special stands at the PA technical diagnostic station in technical service units (units). If there are no such stands in the fire brigade, then the test is carried out at the fire department. In accordance with OST 22-929-76, the reduction in pump pressure at rated flow and impeller rotation speed should not be more than 5% of the rated value for new pumps. The results of running in the pump and testing it are recorded in the fire truck log.

After running in and testing the fire pump, maintenance of pump No. 1 should be carried out. Particular attention must be paid to changing the oil in the pump housing and checking the fastening of the impeller. Every day, when changing the guard, the driver must check: - the cleanliness, serviceability and completeness of the components and assemblies of the pump and its communications by external inspection, the absence of foreign objects in the suction and pressure pipes of the pump; - operation of valves on the pressure manifold and water-foam communications; - the presence of grease in the stuffing box and oil in the pump housing; - lack of water in the pump; - serviceability of control devices on the pump; - illumination in the vacuum tap, lamp in the pump compartment lighting lamp; - pump and water-foam communications for “dry vacuum”.

To lubricate the oil seals, the oiler is filled with lubricants such as solidol-S or pressolidol-S, CIATI-201. To lubricate the ball bearings of the pump, general purpose transmission oils of the type: TAp-15 V, TSp-14 are poured into the housing. The oil level should match the mark on the dipstick. It is recommended to change the oil after 100...120 hours of pump operation.

When checking the pump for “dry vacuum”, it is necessary to close all taps and valves on the pump, turn on the engine and create a vacuum in the pump using a vacuum system of 73...36 kPa (0.73...0.76 kgf/cm2). The vacuum drop in the pump should be no more than 13 kPa (0.13 kgf/cm2) in 2.5 minutes. If the pump does not pass the vacuum test, it is necessary to pressure test the pump with air under a pressure of 200...300 kPa (2...3 kgf/cm2) or water under a pressure of 1200...1300 kPa (12...13 kgf/cm2 ). Before crimping, it is advisable to moisten the joints with a soap solution. To measure the vacuum in the pump, it is necessary to use an attached vacuum gauge with a connecting head or thread for installation on the suction pipe of the pump or a vacuum gauge installed on the pump. In this case, a plug is installed on the suction pipe.

When servicing pumps during a fire or during a training exercise, it is necessary to: place the machine on a water source so that the suction line is, if possible, on 1 sleeve, the bend of the sleeve is smoothly directed downward and begins directly behind the suction pipe of the pump (Fig. 4.32.); to turn on the pump when running the engine needs to squeeze the clutch, turn on the power take-off in the driver's cabin, and then turn off the clutch with the handle in the pump compartment; *immerse the suction mesh in water to a depth of at least 600 mm, make sure that the suction mesh does not touch the bottom of the reservoir; *check before drawing water that all valves and taps on the pump and water-foam communications are closed; *take water from the reservoir by turning on the vacuum system, for which do the following: - turn on the backlight, turn the handle of the vacuum valve towards you; - turn on the gas-jet vacuum apparatus; -increase the rotation speed using the “Gas” lever; - when water appears in the sight glass of the vacuum valve, close it by turning the handle; - use the “Gas” lever to reduce the rotation speed to idle speed; - smoothly engage the clutch using the lever in the pump compartment; - turn off the vacuum apparatus; - use the “Gas” lever to increase the pressure on the pump (according to the pressure gauge) to 30 m; - smoothly open the pressure valves, use the “Gas” lever to set the required pressure on the pump; -monitor instrument readings and possible malfunctions; - when working from fire reservoirs, pay special attention to monitoring the water level in the reservoir and the position of the suction mesh; - after every hour of pump operation, lubricate the oil seals by turning the oiler cap 2...3 turns; - after supplying foam using a foam mixer, rinse the pump and communications with water from a tank or water source; - it is recommended to fill the tank with water after a fire from the water source used only if you are sure that the water does not contain impurities; -after work, drain the water from the pump, close the valves, install plugs on the pipes.

When using pumps in winter, it is necessary to take measures against freezing of water in the pump and in the pressure fire hoses: - at temperatures below 0? C, turn on the heating system of the pump compartment and turn off the additional engine cooling system; - in case of a short-term interruption of water supply, do not turn off the pump drive, keep the pump speed low; - when the pump is running, close the pump compartment door and monitor the control devices through the window; - to prevent freezing of water in the sleeves, do not completely block the trunks; - disassemble the hose lines from the barrel to the pump without stopping the water supply (in small quantities); - when stopping the pump for a long time, drain the water from it; - before using the pump in winter after a long stay, turn the motor shaft and transmission onto the pump using the crank, making sure that the impeller is not frozen; - warm up frozen water in the pump and hose line connections hot water, steam (from special equipment) or exhaust gases from the engine. Maintenance No. 1 (TO-1) for a fire truck is carried out after 1000 km of total mileage (taking into account the above), but at least once a month.

The fire pump in front of TO-1 is subject to daily maintenance. TO-1 includes: - checking the fastening of the pump to the frame; - checking threaded connections; - checking the serviceability (if necessary, disassembling, lubrication and minor repairs or replacement) of taps, valves, control devices; - incomplete disassembly pump (removing the cover), checking the fastening of the impeller, keyed connection, eliminating clogging of the flow channels of the impeller; - changing the oil and refilling the oil seal; - checking the pump for “dry vacuum”; - testing the pump for intake and supply of water from an open water source.

Maintenance No. 2 (TO-2) for a fire truck is carried out every 5,000 km of total mileage, but at least once a year. TO-2, as a rule, is performed in technical service units (units) at special posts. Before carrying out TO-2, the vehicle, including the pumping unit, is diagnosed on special stands.

TO-2 includes performing the same operations as TO-1, and, in addition, provides for checking: - the correctness of the readings of control devices or their certification in special institutions; - the pressure and flow of the pump at the rated speed of the pump shaft at a special stand at the technical diagnostic station or using a simplified method with installation on an open water source and using pump control devices.

The pump flow is measured by water meter shafts or estimated approximately by the diameter of the nozzles on the barrels and the pressure at the pump. The pump pressure drop should be no more than 15% of the nominal value at rated flow and shaft speed; - tightness of the pump and water-foam communications on a special stand, followed by troubleshooting.

Rated by: 4 people

Pumps of fire trucks and motor pumps are tested during each maintenance No. 2 (after a run of 5000 km, but at least once a year) according to the methodology set out in the Manual on the technical service of the State Fire Service. The following conditions must be met during testing:

before starting the tests, it is necessary to check that the installation of pumps and pipelines were carried out in accordance with the requirements of the accompanying technical documentation for the fire truck;

valves, gate valves, and drain valves for water and foam communications of a fire truck must be in good condition and easy to close and open. The serviceability of the pump seal lubrication system is checked. Leaks at connections and controls are not allowed;

the shaft rotation speed of fire truck pumps should not exceed the nominal (specified in the technical documentation) by more than 5%;

the head pressure in the suction pipe of the pumps should not exceed 4.0 kg s/cm2 (0.4 MPa), and for pumps with a shaft seal with plastic packing 8.0 kg s/cm2 (0.8 MPa);

the pressure at the outlet of the fire truck pump should not be more than 11.0 kgf/cm2 (1.1 MPa);

tightness with a rotating impeller is checked by hydraulic pressure created by the pump itself at rated speed;

The start-up of pumps on fire trucks and motor pumps must be carried out with the valves on the pressure pipes completely closed;

the pumps of fire trucks equipped with a gas-jet vacuum system are started only after water appears in the vacuum tap;

If a malfunction is detected during the inspection period, the fire truck pump is immediately turned off. Further tests are carried out after troubleshooting.

Fire trunks, fire columns, branches, adapters, water collectors, etc.

The strength and tightness of the housings of the specified equipment must be ensured at a hydraulic pressure 1.5 times higher than the working pressure, and the tightness of the connections at the working pressure. At the same time, the appearance of traces of water in the form of drops on the outer surfaces of parts and at joints is not allowed.

The frequency of such tests is carried out once a year.

Personal respiratory and vision protection equipment

RPE is tested (checked) within the time limits according to the methodology established by the Manual on the gas and smoke protection service of the State Fire Service.

Fire protective suits

Fire protective suits are tested (checked) within the time limits and according to the methodology established by the manufacturer and the operating instructions.

Manual fire escapes

Manual fire escapes should be tested once a year and after each repair. Before using them in competitions, certificates are submitted for them. The use of manual fire escapes that have malfunctions, damage to main parts or have not passed the test is not permitted.

During testing, a retractable ladder is placed on solid ground, extended to its full height and leaned against a wall at an angle of 75° to the horizontal (2.8 m from the wall to the ladder shoes). In this position, each knee is loaded in the middle with a load of 100 kg for 2 minutes. The rope must withstand a tension of 200 kg without deformation.

After testing, the retractable ladder should not be damaged and the elbows should extend and lower without binding.

The specifics of admitting manual fire escapes to PPP competitions are stipulated by the Rules for holding PSP competitions.

When testing, the assault ladder is suspended freely by the end of the hook and each string at the level of the 2nd step from below is loaded with a load of 80 kg (160 kg in total) for 2 minutes. After testing, the assault ladder should have no cracks or residual deformation of the hook.

When testing, a stick ladder is installed on solid ground, leaned at an angle of 75° to the horizontal and loaded in the middle with a load of 120 kg for 2 minutes. After removing the load, the ladder-stick should not have any damage and should fold easily and tightly.

To test manual fire escapes, a dynamometer can be used instead of hanging a load.

After complete completion of all installation work, installation of the necessary instrumentation, automation, lubrication systems, ventilation devices and the floor of the top covering, a trial run and testing of the pump unit begins.

Before start-up, check the tightening of fastening bolts, threaded connections and seals. Check the lubrication in the system and remove dirt deposits and dust with compressed air. Clean, fresh oil is poured into the crankcase, clutches and gearbox. Manually rotate the clutch, while controlling the smoothness of rotation and the absence of jerking. If the unit is designed to supply hot substances, then before starting it is necessary to warm up the pump with steam with a temperature of at least 40°C from the pumped liquid. The valve located on the pressure pipeline regulates the performance and pressure of the unit's fluid. The first start-up of the pump must be carried out at low load.

The sequence of operations for starting centrifugal pumps is as follows:

• Close all existing valves and taps on all pipelines and instrumentation, except for the valve on the suction pipeline, which can be closed to a maximum of 80%;
• Open the taps to the cooler, oil seals and bearings to supply lubricant to them;
• Open the air outlet valve. Fill the pump and suction pipeline with working fluid;
• Close the air outlet valve. If there is a bypass, open it;
• Start the engine and open the pressure gauge valves;

ATTENTION! It is prohibited to start pumps with the cooling system turned off and not filled with working fluid. It is prohibited to operate the pump for more than 2-3 minutes with the pressure pipeline valve closed.

• When the required shaft rotation speed and nominal pressure on the pressure pipeline are reached, the valve of the pressure pipeline is opened. It is necessary to open it gradually in order to minimize the passage of liquid, thereby avoiding overheating of the engine and pump. If there is a bypass, then it is shut off;
• By monitoring the uniform increase in the load on the engine using instrumentation, open the valve on the pressure pipeline to the operating value.

ATTENTION! If an overload occurs, you must immediately turn off the unit, identify and eliminate the causes of the malfunction.

• To stop, slowly close the valve on the suction pipeline, then on the pressure pipeline and turn off the electric motor.

During operation, it is necessary to monitor the instrument readings. Resistance in the supply line, due to a valve that is not fully open or a blockage, can lead to an increase in pressure.

A uniform oscillation of the instrument needles, except for the voltmeter, indicates normal operation. In case of air leaks in the system, observed sharp jumps instrument arrow. In this case, it is necessary to check the tightness of the connections.

Malfunctions in the pump, as a rule, lead to an increase in the current consumed by the motor.

If knocking or overheating of the pump occurs, it is necessary to stop the unit, identify and eliminate faults.

During a trial run, the test must be controlled:

• Noises and knocks;
• Leaks of working fluid;
• Coolant and lubricant leaks;
• Bearing lubrication and temperature;
• The oil temperature should not exceed 60°C;
• The temperature of rubbing parts and bearings should be no more than 65°C.

The test is considered successfully completed if the pumping unit has operated smoothly and steadily for 2 hours. Next, industrial tests are carried out for 4 hours at full operating load.

List of generally accepted abbreviations (explanations):

• PA - fire truck;
• GVA is a gas-jet vacuum device designed to create a vacuum in the cavity of a centrifugal pump when drawing water from an open water source. It operates using the energy of exhaust gases from an internal combustion engine, directed instead of a PA muffler to a gas-jet pump, the vacuum chamber of which is connected by pipelines to the cavity of a centrifugal pump;
• PN - fire pump;
• Gearbox - gearbox;
• PTO - power take-off, designed to transmit torque from the gearbox input shaft to the PN, activated in the driver's cab by a separate lever. Attached to the gearbox instead of the top cover.
• G-600 - hydraulic elevator, designed for collecting water from hard-to-reach water sources and cleaning up excessively spilled water after extinguishing fires, is a water-jet pump;
• PS - foam mixer. On pumps of the PN-40 series, a foam mixer of the PS-5 brand is installed (provides 1-5 foam generators GPS-600), designed for introducing a foaming agent into the water flow at a concentration of 4-6%, located between the pressure manifold and the suction pipe PN, has in its design water-jet pump and dispenser, can take foam concentrate both from the PA foam tank and from an external container;
• vacuum valve, found in the literature under the name vacuum tap, vacuum shutter, designed to connect and disconnect the cavity of a centrifugal pump with a GVA vacuum chamber, installed on the PN pressure manifold;
• pressure gauge - a device for measuring pressure, installed on the pressure manifold PN, calibrated in kgf/cm2;
• pressure vacuum gauge - a device for measuring pressure, both positive and negative, installed on the suction pipe PN, calibrated in kgf/cm2;
• drain faucet - a plug-type faucet, installed in the lower part of the PN housing to drain water after work, in addition, installed on the pipelines of the additional cooling system of the PA engine;
• tachometer - a device for measuring the number of revolutions of the PN shaft, calibrated in revolutions per minute (rpm), there are mechanical and electrically driven.

Fire pump

Preparing a fire truck for work

When preparing a PA upon arrival at the place of work, you must:

1. Set the PA to the handbrake;
2. Install wheel chocks under the wheels.
3. Attach the necessary hose lines;
4. Set the gearbox lever to neutral position;
5. Turn on the ignition by turning the key to the right until it clicks;
6. Turn on the starter and start the engine.
7. Press the clutch pedal and engage the PTO (to do this, move the gearbox lever towards you and smoothly release the clutch pedal);

Further operations to start the pump depend on operating conditions (water supply from a tank, open reservoir or hydrant). To avoid failure of the clutch release bearing, prolonged operation of the power transmission with the clutch depressed is not allowed.

Checking the fire pump for leaks

When testing a fire pump for leaks:

1. Make sure there is no water in the pump. (If there is water in the pump cavity, intense vaporization is possible in a deep vacuum, as a result of which the creation of a vacuum is impossible). Drain the water through the pump drain cock with the vacuum valve open.
2. Start the engine.
3. Check the tightness of the closure of the drain valve, valves on the pressure pipes, pipes of the foam tank and additional cooling, valves from the tank and into the tank.
4. Turn the handle of the vacuum valve to the “toward” position until it stops. (In this case, the cam of the vacuum valve shaft will press on the rod of the lower valve, which will lead to the connection of the pump cavity through the pipeline with the vacuum chamber of the GVA).
5. Enable GVA. (The valve in the gas distribution mechanism will change its position, open the gas outlet hole into the gas jet vacuum apparatus and close the gas outlet hole into the muffler).
6. Use the throttle control lever to increase engine speed to maximum. (When passing large quantity exhaust gases through the nozzle, vacuum chamber and GVA diffuser, a vacuum is created in the vacuum chamber and in the cavity of the pump).
7. When the gauge needle (see Fig. 1) moves from “0” to 34 between 0 and -1 (which corresponds to 550 -570 mm Hg), Not When releasing gas, turn off the vacuum valve.
8. Reduce engine speed. (At high engine speeds, the exhaust gases press the valve closing the muffler opening so hard that it is impossible to turn off the HVAC).
9. Turn off GVA.
10. Check the readings of the arrow on the pressure-vacuum gauge. If the vacuum changes by more than 100 mmHg within 2.5 minutes. the pump is considered leaky.

Rice. 1. Pressure and vacuum gauge readings when testing the pump for “dry vacuum”. Scale divisions from 0 to -1 are shown conventionally.

Additional explanations:

1. When checking the pump, you should pay attention to the fact that the time required to create the required vacuum should not exceed 20 seconds. The reason for the slow creation of vacuum in the pump cavity may be a decrease in the flow area of ​​the vacuum system due to its clogging or incomplete opening of the vacuum shutter valve due to wear of the cam and valve stem.
2. Vacuum gauges used on fire pumps do not have graduations such as 550 mmHg. and 100 mm Hg. Art. Division “-1” corresponds to -760 mm Hg. Art., or -10 m. water. Art. Taking this into account, the vacuum is brought to 3/4 of the scale to the left of zero. This will correspond to 550 mm Hg.

To determine the causes of vacuum system malfunctions, you can use the following techniques:

• make sure that the pressure-vacuum gauge is working properly. For example, replace it with a known good one (that has passed verification) or test it on another pump.
• Pressurize the pump with water from another pump with a pressure of 8 - 10 kg/cm2. Inspect the pressure pump and repair the leak. If the pump is sealed, then it is necessary to check the tightness of the vacuum system. Create a pressure of 4 - 7 atmospheres with the pump, open the vacuum valve. Inspect the vacuum system. There should be no leaks at the connection points and along the length of the pipeline.
• Check the serviceability of the valve of the gas distribution mechanism; gases should not pass into the siren and into the muffler when the GVA is running.
• The state of the flow section of the pipelines is determined by the amount of water leaving the GVA diffuser when it is supplied under pressure through an open vacuum valve.

Working with a pump without installing a PA on a reservoir

(Water supply from tank)

1. Connect the hose lines to the pressure pipes (in this case, you should strive to keep the number of bends when laying the hoses to a minimum).
2. Using a wrench, check the tightness of the plug on the suction pipe of the pump, as well as valves, gate valves and taps.
3. Open the vacuum valve to allow air to escape from the cavity of the fire pump. (An air lock at the top of the pump cavity prevents water from filling the pump.)
4. Open the tank valve. After water appears in the sight glass of the vacuum valve or from the GVA diffuser, close the vacuum valve.
5. Engage the clutch and increase the speed until the pressure on the pressure gauge is 2 - 3 kgf/cm2.
6. Smoothly open the valve in the hose line.
7. Slowly add gas and bring the pressure to the required value.

Operations upon completion of work:

1. Reduce engine speed to minimum.
2. Disengage the clutch.
3. Close the water supply valve to the pressure line.
4. Close the water supply valve from the tank.
5. Turn off the PTO and the car engine.
6. Open the drain valve from the pump and the vacuum valve.
7. Disconnect the hose lines.
8. Place plugs on the pressure and suction pipes.
9. Clean the hoses and hose equipment from dirt and place them in place with mandatory fastening.
10. Close the compartments securely.

Upon arrival at the garage you should:

1. Replace wet sleeves with a second set, and rinse and dry used ones.
2. Refill the tank with fuel.
3. Fill the oil can to lubricate the pump seals and check the oil level in the pump crankcase.
4. Wash the car thoroughly, clean it of dirt, put the equipment in order.

Typical mistakes when performing the exercise.

1. An attempt was made to supply water to the line without first filling the pump with water. (The presence of air in the pump cavity can lead to a delay in the supply of water to extinguish the fire, making it impossible to create the required pressure).
2. Air release through vacuum - valve when the pump is turned on.
3. Turning the pump on and off at high engine speeds.

Taking water from a reservoir

1. Lower the sleeves with the mesh into the pond. The suction mesh must be lowered at least 300 mm below the water level (to avoid air leaks), but not to the bottom of the reservoir.
2. Check the closure of the drain valve, all valves, valves and taps.
3. (Rotation of the pump shaft when creating a vacuum in the pump cavity is unacceptable).
4. Open the vacuum valve “pull” and turn on the illumination of the inspection window.
5. Turn on the gas jet vacuum apparatus.
6. Use the throttle lever to increase engine speed to maximum. (The characteristic noise of a working HVAC can be heard).
7. When water appears in the viewing window (you can also be guided by the change in the sound of the operating HVAC), wait a short time until the air bubbles stop escaping, then close the vacuum valve (pull-away position).
8. Engage clutch.
9. Turn off GVA.
10. Using the throttle lever, set the water pressure on the pressure gauge to 2-3 kgf/cm.
11. Smoothly increase the pressure to the required value.
12. If necessary, turn on additional cooling of the engine, and first open the drain valve on the pipeline connected to the suction cavity, then open the valve on the pipeline from the pressure cavity of the pump, when water appears from the open drain valve on the pipeline, close it, and open the valve on the pipeline connected to suction cavity. (This operation will prevent air from entering the additional cooling system into the pump cavity).

Typical errors during operation.

1. Insufficient engine speed during HVAC operation.
2. Reduce rotation speed until the vacuum valve closes.
3. High pressure when opening pressure valves.
4. Premature closing of the vacuum valve.
5. Attempts to turn on and off the HVAC at high engine speeds.
6. Engaging and disengaging the clutch at high engine speeds.

Additions and clarifications.

1. After water appears in the inspection window, it is recommended to move the vacuum valve handle to the “away” position at any time of the year in order to purge the vacuum system of water.
2. With low water pressure in the pump, it is easier to open the pressure valves and there is less chance of a water column breaking.
3. When working with one hose line, it is more convenient to connect it to the left branch pipe, because control levers are located on the left.
4. The suction line along its entire length must have a slope towards the reservoir. If in some place it turns out to be raised as a result of being laid through obstacles (bridge railings, reservoir hatch, etc.), then an air plug remains at the upper bend point of the sleeve. When water is introduced into the line, it can cause the water column to break or cause the pump to operate unstably for some time. This must be anticipated in advance when installing the car.

Taking water from a reservoir with a faulty vacuum system

1. Place the car near a pond in compliance with safety measures.
2. Attach the suction arms and suction mesh.
3. Check the closure of the drain cock, all gate valves, valves and the plug valve of the foam mixer.
4. Turn on the power take-off.
5. Disconnect the clutch from the pump compartment.
6. Open the vacuum valve “towards you” and turn on the illumination of the inspection eye.
7. Open the “out of the tank” valve.
8. When water appears in the sight glass, wait until the release of air bubbles stops and close the vacuum valve.
9. Engage clutch.
10. With a pen throttle valves set the water pressure to 1 - 1.5 kgf/cm2 using the pressure gauge.
11. Smoothly open the pressure valve.
12. Carry out activities upon completion of work and arrival at the garage.

Fire truck vacuum system diagram

Vacuum system of a fire truck: 1- body of a gas-jet vacuum apparatus; 2- engine exhaust pipe; 3 — siren resonator (if the siren is gas-jet); 4- dampers; 5‑pipeline; 6 — hole for purging the system after work; 7- vacuum valve body; 8‑cam roller (eccentric); 9- viewing peephole; 10- valve; 11- diffuser; 12 – nozzle; 13‑socket and light bulb.

Note. The position of the lever is in position 1a for purging the vacuum system in winter time; position in position 2a to create a vacuum in the cavity of the fire pump.

Typical errors during operation:

1. An attempt was made to fill the suction line when the suction strainer valve is not closed.
2. Untimely closing of the tank valve.
3. Filling the suction line while the pump is running.

1. The likelihood of a water column breaking is reduced if the valve from the tank is closed after water is supplied to the line.
2. When filling the suction line, the suction strainer valve must be securely closed.

If this condition cannot be met, water can be collected by ringing the tank for which:

1. Close all valves and drain cock;
2. Engage clutch;
3. Open the valve “out of the tank” completely and the valve “into the tank” ¾ of the way;
4. Set the average speed of the pump shaft (2000-1500 rpm according to the tachometer). After filling the suction line and pump with water, the pressure on the pressure gauge will increase sharply and the sound of the engine will change;
5. Smoothly open the pressure pipe valve;
6. Close the “out of the tank” and “into the tank” valves;
7. Set the required pressure.

Filling a tank with water from an open water source

This exercise differs from the usual supply only in that instead of a valve on the pressure pipe, a valve “into the tank” is opened.

However, it must be remembered that internal area the walls of the AC-40 (130) 63B tank truck is 10 m 2. With such an area, even a slight excess pressure (0.5 kgf/cm2) creates a breaking force of 5000 kg.

In order not to rupture the tank, it should be filled under low pressure of 1.5-2 atm. In this case, the control tube has time to pass excess water when the tank overflows.

When water appears from the control tube, the gas is immediately reduced and the clutch is engaged. After this, the valve “to the tank” is closed.

If it is necessary to speed up the filling of the tank, it is necessary to open the lid of the top hatch of the tank and only then increase the pressure. In addition, the initial opening of the valve “into the tank” must be done at minimum pressure.

Water supply

Water supply by fire tankers from a reservoir using a hydraulic elevator

A hydraulic elevator ring for supplying water from a reservoir can be constructed according to the following schemes:

1. Pump - hydraulic elevator - pump.
2. Pump - hydraulic elevator - branching - pump.
3. Pump - hydraulic elevator - tank - pump.

In addition, the hydraulic elevator can be used to remove water from premises by installing the car on a water source.

Starting the hydraulic elevator according to the scheme: “pump-hydraulic elevator-pump”.

Rice. 2. Work according to the “Pump - hydraulic elevator - pump” scheme.

1. Close all taps, valves and valves.
2. Open the tank valve.
3. Engage clutch.
4. When the hose suitable for the water collector of the suction pipe is filled with water, wait some time until the pump operation stabilizes. (The inevitable, with this scheme, air entering the pump cavity makes it difficult to create a closed ring of water in the system. The air will come out through the hydraulic elevator after some time).
5. Close the “out of tank” valve.

Starting the hydraulic elevator according to the scheme: “pump - hydraulic elevator - branching - pump”.

1. Install the tanker at the work site, connect the hoses, branch, hydraulic elevator and trunk.

Check the connections for correctness and eliminate any sharp bends on the sleeves.

Rice. 3. “Working with a hydraulic elevator according to the pump - hydraulic elevator - branching - pump scheme.”

1. Turn on the PTO and disengage the clutch from the pump compartment.
2. Open the tank valve.
3. Release the air from the pump cavity through the vacuum valve, and then close it.
4. Engage clutch.
5. Fully open the valve in the hydraulic elevator pressure line.
6. Increase the pump shaft rotation speed to 2000-2500 rpm.
7. When the hose suitable for the branch is filled with water, slightly open one of the side valves of the branch to release air, and then close it.
8. Fully open the central branch valve that supplies water to the pump.
9. Close the “out of the tank” valve.
10. If necessary, adjust the pump shaft rotation speed, bringing it to 2000-2500 rpm. (At such speeds, the pressure in the suction cavity will be at least 2 - 4 kgf/cm2).
11. Smoothly open the pressure valve to the barrel, making sure that the pressure in the suction cavity of the pump does not fall below 0.5 kgf/cm2.

Starting the hydraulic elevator according to the “pump - hydraulic elevator - tank - pump” scheme

1. Install the tanker at the work site, connect the hoses, hydraulic elevator and barrel.

Check the connections for correctness and eliminate any sharp bends on the sleeves. Use pressure-suction hoses lowered into the tank to avoid kinks (see Fig. 4.).

Rice. 4. “Working with a hydraulic elevator according to the pump - hydraulic elevator - tank - pump scheme.”

1. Close all taps and valves.
2. Turn on the PTO and disengage the clutch from the pump compartment.
3. Open the tank valve.
4. Release the air from the pump cavity through the vacuum valve, and then close it.
5. Fully open the valve in the hydraulic elevator pressure line.
6. Engage clutch.
7. Increase the pump shaft rotation speed to 2000-2500 rpm.

When the water returns to the tank

1. Fully open the valve into the pressure line of the barrel.
2. Set the water pressure on the pressure gauge to 8 kgf/cm2.
3. Monitor the water level in the tank: when it decreases, close the pressure valve to the barrel, and when it increases, open it more and slightly reduce the speed of the pump shaft if the water pressure at the barrel is sufficient.

Additions and clarifications.

This method is the most reliable; it allows you to open the valve to the barrel immediately when starting the system and briefly remove the hydraulic elevator from the water, which is necessary when removing water from the premises.

However this method applicable when working with only one G-600 hydraulic elevator, since the diameter of the tank-pump pipe is only 80 mm. and it cannot ensure the operation of two hydraulic elevators.

On currently produced fire trucks, the diameter of the tank-pump pipe is increased, or two pipes with a diameter of 80 mm with separate valves are installed.

In addition, constant monitoring of the water level in the tank with the help of an observer is necessary. Monitoring the water level using level sensors is not operational, which does not allow balancing the flow of water and its consumption. In previous methods of working with a hydraulic elevator, this balance is obtained automatically.

Water harvesting using a hydraulic elevator with vehicle installation at a water source

If there is a water source (hydrant or reservoir), it can be used when cleaning (pumping) water from the premises. To do this, water from the water source is pumped into the pressure line of the hydraulic elevator, and from the hydraulic elevator to the drain.

Rice. 5. Scheme of water harvesting using a hydraulic elevator.

This scheme is more reliable in operation than a closed hydraulic elevator ring and does not require special skills in operation. In some cases, when the pressure in the hydrant is 3 - 4 kgf/cm2, water can be removed without installing the car at the water source, by connecting the pressure line of the hydraulic elevator directly to the fire column.

Maximum use of fire truck power when pumping water

When carrying out emergency rescue operations, as well as in other cases, if the water level in a flooded room is high and it is possible to collect water using suction hoses, then the following scheme for using hydraulic elevators can be recommended.

Rice. 6. Scheme of vehicle operation at maximum power during pumping.

In this case, the volume of pumped water per second when using the PN-40U pump will be about 70-75 l/sec.

Supply of air-mechanical foam without installing a fire truck on a pond

1. Connect the hose line to the foam generator.
2. Check that the plug on the pump suction pipe is tightly tightened. Close all valves and taps.
3. Open the vacuum valve (pull towards yourself) to ensure air escapes from the cavity of the fire pump.
4. Open the valve from the tank. After water appears in the viewing window of the vacuum valve, close it.
5. Engage clutch.
6. Smoothly open the pressure valve into the hose line.

11. Reduce pressure to 1.5 - 2.5 kgf/cm2.

12. Close the valve for supplying foam concentrate from the foam tank.

Failure to perform the operations of washing the foam mixer leads to polymerization and subsequent hardening of the foam concentrate in the dispenser!

1. Carry out the actions necessary to complete the work.

Supply of air-mechanical foam with installation of a fire truck on a pond

1. Place the car near a pond in compliance with safety measures.
2. Attach the suction arms and suction mesh.
3. Lower the sleeves with the pond mesh. The suction mesh must be lowered at least 300 mm below the water level (to avoid air leakage), but not to the bottom.
4. Check the closure of the drain valve, valves and plug valve of the foam mixer.
5. Turn on the power take-off.
6. Disconnect the clutch from the pump compartment.
7. Open the vacuum - the valve "pull" and turn on the backlight.
8. Turn on the gas jet vacuum apparatus.
9. Use the throttle lever to increase engine speed to maximum. (The characteristic noise of a working HVAC can be heard).
10. When water appears in the viewing window, wait a short time until air bubbles stop escaping, then close the vacuum valve - away from you.
11. Reduce engine speed to idle speed.
12. Engage clutch.
13. Turn off GVA.
14. Using the throttle lever, set the water pressure on the pressure gauge to 1-1.5 kgf/cm2.
15. Open the plug valve of the foam mixer.
16. Set the dispenser arrow to the number corresponding to the number of foam generators supplied.
17. Open the valve on the “foam tank - foam mixer” pipeline.
18. Smoothly open the pressure valve into the hose line.
19. Increase pressure to 6 kgf/cm2.

After supplying foam, without turning off the pump:

1. Reduce pressure to 1.5 - 2.5 kgf/cm2.

Close the foam concentrate supply valve from the foam tank.

Foam mixer cleaning operations!

1. Open the tap on the water tank-foam mixer pipeline.
2. Turn the handwheel of the foam mixer dispenser in any direction, making at least 4 - 5 full turns.
3. Make sure that the foam generator comes out pure water no signs of foaming agent.
4. Close the plug valve of the foam mixer.
5. Carry out the actions necessary to complete the work.

Additions and clarifications

As you noticed, operations for supplying air-mechanical foam, at the initial stage, are no different from operations for supplying water, with or without installing a fire truck at the water source. But at the same time, when supplying air-mechanical foam, it is necessary to even more carefully control the removal of air from the pump cavity before engaging the clutch.

If there is even a small amount of air in the pump cavity, in the presence of a foaming agent, the pump impeller whips up air-mechanical foam when rotating, which fills the free space.

This can also happen if the flushing of water and foam communications is carried out poorly and the water is not drained from the pump.

IMPORTANT:

The presence of a foam plug in the pump cavity makes it impossible to supply water or foam to extinguish a fire!

It takes considerable time to remove it using a gas-jet vacuum apparatus or by releasing it through pressure pipes.

Video about fire pumps