What are the self-test methods and advantages of the fire pump


The self-inspection of the fire pump is also a very important part. If this aspect is not understood, it will have a great impact on the use of the fire pump. The work that needs to be done before the self-inspection method is; to understand the fire pump in advance, It is also necessary to detect and prevent some errors in the process of use. This kind of inspection is mainly divided into two types, one is the normal speed self-test method, and the other is the low-speed self-test method

1. Isokinetic self-test method.

Now this kind of fire pump generally adopts the method of self-calibration and constant speed during self-inspection, because this method has lower requirements and does not need to spend too much time on debugging. In the process of this constant-speed self-inspection, the The whole process of starting and running the fire pump. The above effect is better. Simulate the running process of fire water within a certain running time. There is a key link in these operations that needs special attention, that is, the fire pump will be released after the constant speed self-test , to prevent problems during use.

2. Low-speed self-test method.

This method has fewer inspections, so the use time is very short. When the self-inspection method is in a low-speed state, if the fire pump has a large volume and volume, the fire pump cannot be opened directly, and indirect guidance is required. When the inspection is in the early inspection work link, so the subsequent work is to check out the fault.

The use of fire pumps makes our transportation of liquids more convenient and fast. The use of these is also very obvious for heating effects.

Therefore, the use of XBD fire pumps has brought convenience to all aspects of our lives, and the liquid substances that can spread have led to the development of many projects. In addition, it can save labor. The installed fire pump series, sealing and corrosion resistance , so it is a very good guarantee for environmental protection, which and our country is now promoting environmental protection and health.

In addition, it can also transmit physical and chemical liquid substances, which greatly reduces labor costs and labor intensity, and is very helpful to the environment. Because of its relatively small scale, it can be applied anywhere, and the angle can be adjusted arbitrarily. Comes great convenience. We have great significance for everything, but I have to say that XBD fire pump has brought great convenience to our life, you can feel it from your mobile phone, the answer is no, the same Yes, now it is difficult to leave the fire pump, industrial development.

Multi-stage fire pump operation method and what are the characteristics between the suction pipe and the outlet pipe

The main purpose of the vertical fire pump is to transport clear water without solid particles, or a liquid that is particularly similar to water. Its function is to pressurize and deliver water to the fire protection system. Of course, it also has the function of drainage. The pressure range of the transported liquid is 0.2~2.25 MPa. The caliber range is; 50~; 200mm. The water flow range is 5~80L/s.

The main purpose:

Vertical fire pumps are mainly used in pipeline pressurized fire protection systems. They can also be used in industrial and urban water supply and drainage, high-rise building pressurized water, long-distance water, hot and cold water cycle pressurized heating, toilets and boilers, water supply and supporting equipment for air-conditioning and refrigeration systems equipment etc.

A new vertical multi-stage fire pump, including water inlet section, middle section, outlet section, impeller, main shaft and guide vane, the impeller is installed in the guide vane and discharge section through the main shaft, and the guide vane is set in the middle. Shell shape, the final stage impeller is directly installed in the volute.

The new vertical multi-stage fire pump has no final guide vane in the outlet section. The water is directly discharged from the end impeller, then enters the volute channel in the outlet section, and then discharged from the water outlet. This can improve the flow state of water, reduce energy loss, and improve Pump efficiency, greatly reducing the vibration and noise of the pump.

Fire pumps are mainly used in pipeline pressurized fire protection systems. They can also be used in industrial and urban water supply and drainage, high-rise building pressure water supply, long-distance water, hot and cold water cycle pressurized heating, toilets and boilers, air-conditioning and refrigeration system water supply and supporting equipment, etc.

(1) Two or more suction pipes, when one of the suction pipes is under maintenance or damaged, the rest of the suction pipes should still pass 100% of the total water consumption, production and fire water pump room life and share, when life and production For water use, 100% of fire-fighting water should still be guaranteed; for the fire-fighting water pump room set independently, when the suction pipe is damaged, other water suction pipes should still ensure 100% water consumption.

(2) High-pressure fire pumps, fire pumps, and fire pumps should have independent suction pipes to ensure that the fire pool or municipal pipe network can directly absorb water and provide fire water.

(3) Appropriately use the tank body to absorb water. This water absorption method is often used to fill the fire pump, which can quickly start the fire pump to ensure fire water. If there is any difficulty, reliable water filling equipment should be provided.

(4) In order to ensure that the circular pipeline has a reliable water source, the fire pump should not be smaller than two outlet pipelines and be connected with the circular pipeline. When two outlet pipelines are used, each outlet pipeline should be able to satisfy all water supply. As a maintenance process One of the outlet pipes, the rest of the pipe can still provide all the water. The outlet pipe of the pump and the loop system should be connected on different sections to ensure the safety of water supply.

The fire pump should run regularly or regularly, lubricate the part, and measure the pressure and flow after starting the fire pump. Therefore, set the fire pump outlet pipe to check and test the drain valve.

How to start the fire pump and how to deal with the noise
The starting methods of the fire pump can be divided into several starting methods, and each starting method has certain significance. When starting, you can choose from the following options. The starting relationship between the control room and the fire hydrant action button and the starting form of the fire hydrant pump related.

There are generally two ways to start the fire pump. One way is the diffusion bus mode. The start of the fire hydrant action button can be sent to the console of the fire control room according to the start signal of the fire hydrant linkage interface module located nearby. Fire hydrant activation switch output.

Directly output the switch of the fire hydrant action button to the fire pump starter box. These two starting methods can be used in the actual design. There is one method before wiring, but the address code programming of the fire hydrant linkage module should be performed under the bus system , to achieve the purpose of monitoring a large number of fire hydrants.

The latter method is simple and reliable, but the action signal of the fire hydrant needs to be fed back to the fire room. In the specific design, the designer can be selected according to the actual size of the actual project. The project scale is large and the construction form is complicated, so it can be used for the start of the former type. , the small size can be used after the start of work.

Pump noise is the irregular, intermittent, continuous or random noise generated by the pump during operation. The noise produced by the water pump will directly affect the lives of the surrounding residents, so how to eliminate the noise has become a crucial issue. Today, Shanghai Zibo Zhengji Pump Industry Co., Ltd. will teach you how to solve the noise of the water pump.

1. Distance noise reduction

The farther away the noise source is, the lower the noise will be. In the design, the water pump room should be set as far as possible outside the building and independently, so that it can be far away from the noise source. However, in reality, the water pump room is mostly set in the basement of the building, which requires us to There must be other methods.

2. Vibration isolation and vibration reduction can reduce noise

Isolate the noise source to isolate the noise generated by the water pump, and minimize the chance of the noise source being transmitted to other structures. The water pump is required to do a good job of vibration isolation and vibration reduction to isolate the vibration source caused by the pump work. At present, rubber vibration isolation pads and strong spring shock absorbers are commonly used; vibration isolation measures should be taken on the inlet and outlet pipelines of fire pumps, and rubber shock absorbers should be installed. Throat to reduce the noise transmitted along the pipeline. At the same time, the water distribution pipeline in the pump room must be equipped with vibration-isolated elastic supports to minimize the possibility of noise transmission. Vibration isolation and vibration reduction measures are effective in design and technical measures For a detailed introduction, relevant national standard atlases can be selected during design.

3. Sound insulation, sound absorption and noise reduction

The pump room located in an important building that requires noise should be further treated with sound insulation and sound absorption. Materials with good sound insulation performance should be used as building materials for the pump room, and materials with good sound absorption materials should be used for the walls of the pump room. Surface and roof are treated with sound-absorbing treatment to minimize noise.

Eleven Tips for Fire Pump Troubleshooting and How to Repair and Maintain
Fire pump does not turn on when starting

Reason: The packing is too tight or the impeller and the pump body are blocked by debris; the pump shaft, bearing, and leakage ring are rusted; the pump shaft is seriously bent. Remedy: Loosen the packing, dredge the water diversion tank: disassemble the pump body to remove debris or rust; correct the bent shaft or replace the pump shaft with a new one.

After starting, the water pump does not produce water

Reasons: There is air in the pump or gas accumulation in the water inlet pipe; the bottom valve is not closed tightly and the water is not filled, the vacuum pump packing is seriously leaking; the gate valve or flap door is not closed tightly. Remedy: remove debris, replace the damaged rubber pad, change the direction of the valve plate; press or replace the new packing, close the gate valve or flap the door; increase the amount of water until there is no air bubbles at the vent plug; replace the Cracked pipe water; reduce the head and press the nozzle of the water pump into the water 0.5 meters.

Insufficient flow

Reasons: the actual head of the fire pump exceeds the allowable head; the speed is not matched or the belt is slipping, and the speed is low; the installation angle of the blade of the axial flow pump is too small; the suction is too high; the bottom valve, pipeline and impeller are partially blocked or the impeller is defective; the outlet pipe Leakage is serious. Remedy: reduce the head, restore the rated speed, remove the dirt on the belt and adjust the belt tightness; adjust the blade angle, lower the installation position of the water pump; tighten the gland, seal the leak of the water pump, compress the packing or replace the packing; remove the blockage, Replace the impeller; replace the leak ring to block the leak.

The flow rate changes from large to small

Reason: The filter screen or bell mouth is gradually blocked by debris; the dynamic water level is lowered, and the submerged water depth of the water inlet pipe is not enough. Elimination method: remove sundries, increase the depth of the bottom valve into the water.

Overhaul and maintenance

1. After the fire pump is out of service, the remaining water in the pump and pipeline should be drained, and the internal soil should be cleaned to prevent the pump body and water pipe from bursting due to the freezing of accumulated water after freezing.

2. The iron castings such as the bottom valve and elbow of the fire pump should be cleaned with a wire brush, and then painted with anti-rust paint before painting, and then put them in a ventilated and dry place in the machine room or storage room after drying custody.

3. If it is driven by a belt, remove the belt, wash and dry it with warm water, and then hang it in a dry place without direct sunlight, and do not store it in a place with oil, corrosion and smoke. Under no circumstances should the belt be stained with oily substances such as engine oil, diesel or gasoline, and do not apply rosin and other sticky substances.

4. Check the ball bearings. If the inner and outer jackets are worn, moved, worn or spotted on the surface, they must be replaced. For those that do not need to be replaced, the bearings can be cleaned with gasoline or kerosene, coated with butter, and reinstalled.

5. Check whether the impeller of the water pump has cracks or small holes, and whether the fixing nut of the impeller is loose. If there is any damage, it should be repaired or replaced. If the impeller wears too much or has been damaged, it should generally be replaced with a new impeller. Partial damage can be repaired by welding, and the impeller can also be repaired with epoxy resin mortar. The repaired impeller should generally undergo a static balance test. Check the clearance at the impeller wear-reducing ring, if it exceeds the specified value, it should be repaired or replaced.

6. For pump shafts that are bent or severely worn, they should be repaired or replaced, otherwise it will cause imbalance of the rotor and wear of related parts.

7. Soak the removed screws in diesel oil, brush them with a steel wire brush, apply engine oil or butter, reassemble them or wrap them in plastic cloth and put them away (it can also be stored in diesel oil) to avoid rust or loss.

Fire pump fault elimination measures and how to set fire pump control

Usually in the maintenance process, the diagnosis of fire pump faults is a key link. Here are several common faults and elimination measures for everyone to diagnose fire pump faults in a targeted manner.

1. No liquid supply, insufficient liquid supply or insufficient pressure

1) The pump is not filled with water or not vented properly Elimination measures: Check whether the pump casing and inlet line are completely filled with liquid.

2) The speed is too low Elimination measures: Check whether the wiring of the motor is correct, whether the voltage is normal or whether the steam pressure of the turbine is normal.

3) The water head of the system is too high Elimination measures: Check the water head of the system (especially the friction loss).

4) Suction lift is too high Elimination measures: Check the existing net pressure head (too small or too long inlet pipeline will cause great friction loss).

5) The impeller or pipeline is blocked Elimination measures: Check for obstacles.

6) The direction of rotation is incorrect Elimination measures: Check the direction of rotation.

7) Air is generated or there is leakage in the inlet pipeline Elimination measures: Check the inlet pipeline for air pockets and/or air leakage.

8) The stuffing or seal in the stuffing box is worn, causing air to leak into the pump casing Elimination measures: Check the stuffing or seal and replace it if necessary, check whether the lubrication is normal.

9) Insufficient suction head when pumping hot or volatile liquid Elimination measures: Increase the suction head and consult the manufacturer.

10) The bottom valve is too small Elimination measures: Install a bottom valve of the correct size.

11) The immersion depth of the bottom valve or the inlet pipe is not enough Elimination measures: consult the manufacturer for the correct immersion depth. Use baffles to eliminate eddy currents.

The first interface control method: the fire module outputs DC24V active signal control (that is, the fire module logic starts the pump, according to the principle drawing of the control cabinet provided by the manufacturer, this control method can realize the mutual switching function of the main and standby pumps, that is It is reasonable to use a module to control the automatic start-up pump. We believe that this control method can meet the relevant fire protection regulations).

The second interface control method: emergency control (from the fire control center to the pump control cabinet): is this emergency control method controlled by the water pump control cabinet (each pump control cabinet only uses a set of hard pull wires for control), or According to the water pump control (leave one interface for each pump and use three sets of hard pull lines to control the start and stop of the three pumps respectively)? To make this control method clearer, I would like to ask: Does the "fire emergency control (hard pull line control)" need to be controlled by the mutual switching circuit in the pump control cabinet or directly through the respective pump buttons of the fire control center to forcibly start the pump? If the fire control center button is used to forcibly start the pump, can it pass the fire department's acceptance? If it fails, where is the relevant specification to prove this problem?

The third interface control method: through the pressure switch on the alarm valve to start the pump, this control method is not considered for the time being, and it is just a control description here.

The fire pump starts usually in the following ways:

1. The fire pump control cabinet in the pump room starts the pump directly.

2. The multi-line module of the fire alarm host is activated. There is a multi-line control panel on the panel of the alarm host, and the corresponding start and stop buttons are on it, which is the first situation you mentioned.

3. Control the start and stop of the pump by relying on the change of the pipe network pressure, including: electric contact pressure gauge, pressure switch, etc. This is the case. This is the third case you mentioned.

Fire pump power saving measures and how to make the fire pump run smoothly
1. Adopt high-efficiency and energy-saving water pumps and high-efficiency and low-loss motors, and improve the efficiency of transmission devices.

2. Correctly select the power of the pump motor. Prevent "big horses and small carts". Replace the overcapacity water pump motor. When the power of the motor is much greater than the actual need, the method of replacing the motor can be used to save electricity.

3. Choose a reasonable lift. When the head of the pump leaves too much margin. It will waste electric energy, so the head of the pump's operating point should be reasonably determined. 4. Reduce pipeline resistance. Eliminate redundant pipe fittings, unnecessary turns and sharp angles on the pipeline to reduce pipeline resistance and reduce unit power consumption for water delivery.

The methods to reduce pipeline resistance include:

①. Pipeline design should be reasonable.

②. Increase the pipe diameter or use double pipe drainage to reduce the flow rate.

③. Shorten the length of the pipeline as much as possible, reduce joints, elbows and valves, and especially avoid the appearance of sharp angles.

④. Improve the smoothness of the inner wall of the pipeline or add a coating.

⑤. Remove the dirt on the inner wall of the pipeline in time.

5. Water pump speed regulation saves electricity. The power consumption of the water pump is proportional to the cube of the speed of the unit, so the speed of the unit should be changed according to the actual load conditions. Can greatly save electric energy. Adopting pump speed regulation measures, the initial investment is relatively large, but the power saving effect is remarkable, especially suitable for large-capacity water pumps. It should be noted that the larger the head, the flatter the resistance curve, even if the speed changes slightly, the flow rate will change greatly, and the power saving effect is poor.

6. Transform the pump impeller. When the flow rate of the pump in use is larger than the actual flow rate required, and the speed control cannot be used or the price of the speed control device is uneconomical, the impeller of the original pump can be turned or replaced to reduce the flow rate and Head, in order to reduce the running power consumption of the pump.

If the feedwater pump is designed using the same conversion method, after obtaining the speed n of the required operating conditions, the individual arcs of the corresponding operating conditions can be converted according to the formula: or the rotating speed and multi-stage The characteristic curve of the fire pump's initial and final operating conditions is the first step in the design and calculation of the feed water pump. In order to make the feed water pump run quietly and reliably under all operating conditions, the extremely serious condition is to ensure that no cavitation occurs under each operating condition, and the guarantee condition for no cavitation should be given by the front Booster pump supply for the water pump. Design and calculation of pre-boosted fire pump The pre-boosted pump is referred to as the booster pump for short, it is placed before the suction of the boiler feed water pump, and provides the feed water pump with sufficient suction pressure to avoid cavitation under operating conditions . Before designing and calculating the booster pump, it is necessary to first confirm the design calculation flow and head value of the single-stage fire pump. It is precisely because of the connection between the booster pump and the feedwater pump that the exact design and calculation parameters of the booster pump are all related to the corresponding working condition parameters of the feedwater pump.

The impeller is eccentrically installed in the pump body. When the impeller rotates according to the correct direction, the water entering the fire pump body is thrown to the limit by the impeller. Due to the influence of centrifugal force, the water forms a uniform thickness similar to the pump cavity. closed water ring. The upper inner surface of the water ring happens to be tangent to the impeller hub, and the lower inner surface of the water ring just meets the top of the blades (actually, the blades have a certain insertion depth in the water ring). At this time, a crescent-shaped space is formed between the hub of the impeller and the water ring, and this space is divided into several small cavities equal to the number of blades by the impeller. If starting from the upper part of the impeller at 0°, then when the impeller of the fire pump rotates 180° before the rotation, the volume of the small chamber gradually increases from small to large, the pressure decreases continuously, and it communicates with the suction port on the suction and exhaust pan , when the pressure in the small chamber space is lower than the pressure in the pumped container, according to the principle of gas pressure balance, the pumped gas is continuously drawn into the small chamber, and it is in the process of inhalation.

When the inhalation is completed, it is isolated from the inhalation port, the volume of the small cavity is gradually decreasing, and the pressure is continuously increasing. exhaust. And the volume of the small cavity communicated with the exhaust port further reduces the pressure to further promote. When the pressure of the gas is stronger than the exhaust pressure, the compressed gas is discharged from the exhaust port. During the continuous operation of the pump, Continuously carry out the process of suction, compression and exhaust, so as to achieve the purpose of continuous pumping.

In the water ring pump, the auxiliary exhaust valve is a special structure, generally using a rubber ball valve, its function is to submerge the phenomenon of over-compression and under-compression generated during the operation of the pump. Both phenomena will cause excessive power consumption. In order to solve this problem, a rubber ball valve is generally installed under the exhaust port, so that when the fire pump chamber reaches the exhaust pressure prematurely, the ball valve will automatically open and the gas will be discharged, eliminating the over-compression phenomenon. Generally, when designing a water ring pump, the minimum suction pressure is used to determine the compression ratio, so as to determine the starting position of the exhaust port, so as to solve the phenomenon of insufficient compression.