Why is the diesel engine fire pump very hot after starting for a while?

As people's awareness of fire protection continues to increase, various enterprises, units, and individuals pay more and more attention to fire protection systems, and diesel engine fire pumps are also favored by more and more people. With the development of the fire fighting equipment industry, the various automation performances of diesel engine fire pumps are becoming more and more perfect. The diesel engine fire pumps developed so far have various automation, intelligence, remote control, automatic alarm and other functions.

We all know that when a fire breaks out, the circuit is very easy to be forced to short circuit or open circuit. At this time, if it is an electric diesel engine equipment, it will not be able to start, which will affect the normal operation of the fire pump equipment, which may cause huge losses.

In contrast, the diesel engine pump set has greater advantages and is independent of the power supply system. There may be various problems in the operation of the equipment, among which excessive temperature is one of the common phenomena. The professional technicians of Shanghai Xizhiquan summed up the following several possibilities that lead to the overheating of the diesel engine fire pump.

1. Overwork;
2. The oil radiator is blocked, resulting in poor heat dissipation;
3. The adjustment switch of the oil temperature is improperly operated, and the engine oil is not well dissipated;
4. The cylinder leaks, and high-temperature gas enters the oil pan, causing the temperature of the oil in the oil pan to rise;
5. The cooling fan of the air-cooled machine has not played an effective role. It may be that the speed is too low, which leads to an increase in the body temperature of the diesel engine.


In order to better ensure the reliable operation of the fire protection system, it is inseparable from perfect daily management. Although with the development of science and technology, the current diesel engine fire pump has various intelligent features, zjbetter's perfect management is essential, and regular inspection is very important.

Diesel fire pumps have four "automatic" advantages
Diesel engine fire pumps can be used for emergency water supply in community buildings or factory warehouses. When a fire occurs, the power supply fails, and the electric fire pumps cannot be put into use normally, the diesel engine fire pumps can be automatically started and put into operation according to the signal to provide fire water supply to ensure Fire extinguishing is carried out normally.
Diesel engine fire pump is a kind of electromechanical integrated equipment that is directly driven by fire pump and can start and complete water supply in a short period of time. The pump set is driven by diesel and does not need an external power supply. It is suitable for various fire water supply occasions such as agricultural irrigation, emergency rescue, smelting, hangars, petrochemical oil depots, liquefied gas stations, and textiles. Especially when the power supply is not satisfactory, diesel engines are used. Driving water pumps is a reliable and guaranteed equipment choice.

The diesel engine fire pump has a high degree of automation and can be connected to the control center according to the needs. It is easy to install and use, easy to maintain and maintain, and also has automatic, manual and fault self-checking functions. The whole process monitors the working status, can restore the function of automatic restart after failure of starting, automatic pre-lubrication and pre-heating, making the equipment start-up safer and more reliable.

Diesel engine fire pumps are equipped with various automatic functions to meet the requirements of national standards, ensuring long-term normal standby of the equipment and putting it into fire fighting work at any time. The four "automation" advantages of Xizhiquan diesel engine fire pump are summarized:

1. Automatic operation: When the diesel engine pump unit receives an effective fire signal or remote control start signal, the equipment will automatically start and run; when the electric fire pump power supply system is powered off or loses a signal, the unit will automatically stand by. Start for 10S, if it cannot start and run, it will stop for 10S, and then restart, the unit will automatically repeat three times

2. Automatic charging: Stand by in the automatic position at ordinary times. If the battery voltage is too low, it can use the mains to automatically charge; when the battery voltage is sufficient, it will automatically stop charging to avoid damage to the battery and ensure the smooth start of the unit.

3. Automatic alarm: multiple startup failure alarm, diesel engine low oil pressure alarm, diesel engine water temperature super high alarm, diesel engine overspeed alarm, battery low voltage alarm, charging failure alarm, fuel shortage indication alarm

4. Automatic preheating: make the diesel engine in a hot engine standby state to ensure emergency work at low temperature

Fire-fighting facilities play a key role in the safety of buildings and the safety of people's lives and property, so the management and maintenance of fire-fighting facilities is very important. We usually have a variety of fire-fighting tools in common fire-fighting facilities. For example, gas fire extinguishing system, foam fire extinguishing system, dry powder fire extinguishing system and sprinkler system, etc., tools for evacuation and escape, and tools for flame retardant and fire prevention. Today I will tell you about the fire pump unit in the category of fire fighting.

As a manufacturer of fire pumps for more than ten years, zjbetter is mainly engaged in products such as XBD electric fire pump sets, XBC diesel engine consumption pump sets, 3CF fire pump control cabinets, SDC fire dual power water supply equipment, and W fire stabilized pressure water supply equipment. The fire pump is an integrated device that directly drives the fire pump with power and can start and complete the water supply in a short period of time. With the continuous development of technology, today's fire pumps use intelligent control equipment to connect to the control center, which has a higher degree of automation and is safer and more reliable.
So how to choose between electric fire pump and diesel engine fire protection? In fact, these two types of equipment are not either-or, but complementary to each other. In other words, the diesel engine fire pump set can provide double insurance for the electric fire pump set, because it increases the emergency capability of the fire pump set. When a fire alarm occurs or the mains power is cut off, the diesel engine fire pump unit can automatically start the water supply to extinguish the fire according to the signal, which is suitable for more fire water supply occasions. In the case of no electricity or power failure, it is a safer choice and guarantee to choose a diesel engine to drive a fire pump.

Zjbetter’s diesel engine fire pump sets are equipped with diesel engines with good starting characteristics, strong overload capacity, compact structure, convenient maintenance, simple use, and high degree of automation. There are many brands available for selection. Imported diesel engines include American Cummins, Caterpillar, etc. Le, Volvo, Daewoo, Doosan, Fiat, Hatz; domestically produced diesel engines include Dongfeng Cummins, Quanchai, Shanghai Diesel, Weichai Power, Isuzu, Yuchai, CSIC, Beijing Beinei, etc. The diesel engine fire pump can be installed together with the fire control cabinet. It has a high degree of automation, complete functions, automatic fault alarm, accepts the start signal, completes the start procedure by itself, and quickly puts into operation.

Zjbetter diesel engine fire pump adopts a number of new technologies, new materials, and new structures. It is quick to start, easy to use, and stable in operation, which can meet the needs of fire water supply in various emergency situations. If you are purchasing a fire pump, it is recommended that you can use the electric fire pump as the main fire pump and the diesel engine fire pump as the backup fire pump. For more details about fire pumps, please contact our customer service on the homepage of the zjbetter official website.

The diesel engine fire pump adopts a large-capacity fuel tank, which can greatly increase the continuous running time of the generator. When there is no power supply or the power is cut off, it can be used in conjunction with the electric fire pump. Today's diesel engine fire pumps have a high degree of automation, superior technology and performance, complete protection functions, and simple operation. In addition to the previous manual control, equipped with a complete set of intelligent control cabinets, the diesel engine fire pump has the advantage of automatic control. When the self-start signal is input or the start button is pressed manually, the self-start, unit operation, fault shutdown protection, etc. are automatically completed.
The diesel engine fire pump is driven by the diesel engine through an elastic coupling. It has the advantages of reasonable structure, high efficiency, good cavitation performance, small vibration, low noise, stable and reliable operation, and convenient assembly and disassembly. As a fixed fire fighting equipment, diesel engine fire pump has been widely used in fire rescue.

However, during the operation of the diesel engine fire pump, there will be blue smoke, which is usually caused by the burning of engine oil after the diesel engine has been used for a long time. With the increase of the blue smoke, the diesel engine should be repaired in time; There is moisture, or moisture leaks into the combustion chamber, causing changes in combustion, resulting in light blue smoke from the diesel engine fire pump.

Let's analyze it in detail:

1. The air filter is blocked, the air intake is not smooth or the oil level in the oil basin is too high, which reduces the amount of gas entering the cylinder and changes the normal ratio of the fuel mixture gas, resulting in incomplete combustion of fuel with more oil and less gas, causing exhaust leakage blue smoke.

2. Long-term low load, running below 40% power, the gap between the piston and the cylinder liner is too large, so that the lubricating oil in the oil pan is easy to escape into the combustion chamber, mix with the fuel mixture in the cylinder, and change the normal state of the mixture Ratio, incomplete combustion, causing blue smoke.

3. If too much lubricating oil is added to the oil pan, the lubricating oil will easily enter the combustion chamber during the operation of the diesel engine, and blue smoke will also be produced.

4. The piston ring is stuck or worn too much, and the elasticity is insufficient. When installing, the chamfering direction of the piston ring is reversed, so that the engine oil enters the combustion chamber, and the blue water vapor smoke is emitted after the lubricating oil is burned.

5. The vent hole between the crankcase breather and the atmosphere is blocked, resulting in high pressure of the crankcase exhaust gas, and the engine oil goes up to the combustion chamber to participate in the combustion, and blue smoke comes out.

6. The cylinder head gasket near the oil passage leading to the cylinder head is burned, the piston cylinder liner is worn, and the piston ring is matched, which will cause the lubricating oil to go up the combustion chamber and burn together with the fuel mixture.

In short, the "blue smoke" of the diesel engine fire pump is actually a signal that your equipment needs to be cleaned, inspected, repaired or replaced. Because the diesel engine fire pump is a precision instrument, if there is a problem, you can contact the manufacturer or a professional technician to operate it, and do not do it blindly.

The countermeasures for common failures of fire pumps are summarized, and I hope to give you some references when needed.

1. Countermeasures to prevent fire pump air binding

Centrifugal fire pumps need to be manually filled with liquid before starting to clear the air accumulated in the pump casing. When filling the pump, ensure that the bottom valve of the suction line is well closed; For fire pumps, it is necessary to ensure that the automatic filling pump system works normally; regularly check the tightness of the suction pipeline to prevent the air from being sucked in due to poor sealing, and to avoid air binding during the operation of the pump and affect the work.

2. Countermeasures to prevent fire pump cavitation

Control and adjust the installation height of the pump so that the installation height between the suction port of the pump and the liquid surface does not exceed the maximum allowable installation height, especially for mobile fire pumps, if they cannot absorb and discharge liquid normally, the installation height may be inappropriate. It can be solved by reducing the installation height or reverse installation;

Or add a small-capacity storage tank in front of the pump to increase the height of the liquid level and increase the static pressure, thereby shortening the distance between the liquid level of the suction storage tank and the suction port of the pump to prevent cavitation;

It can also prevent cavitation by reducing the flow resistance loss on the pump suction line. Shorten the length of the suction pipeline as far as possible within the allowable range, reduce the number of pipe fittings such as elbows and valves, and appropriately increase the diameter of the suction pipeline;

By improving the strength and abrasion resistance of the pump material, it can also effectively reduce the erosion of the pump caused by cavitation, so as to reduce the damage caused by cavitation to the pump and prolong its service life. In the selection of the impeller, it is possible to choose high hardness and high elasticity materials with strong cavitation resistance.
3. Prevent overloading of the motor of the electric fire pump

Correctly select the supporting motor that matches the performance parameters of the pump to prevent the motor from being too small and overloaded for a long time; before starting the pump, check whether the outlet valve is fully closed to prevent the motor from being burned due to excessive starting current; The technical parameters of the motor require maintenance, check the power supply voltage and the current of each phase, and ensure that the error is within the allowable range.

4. Prevent abnormal vibration and wear of the fire pump

The fire pump should be installed firmly, and its firmness should be checked regularly, especially the anchor bolts or backrest bolts, to prevent the fasteners from loosening;

Strengthen monitoring by monitoring the vibration waveform of the pump during operation, regularly check and repair the wear between the impeller and the sealing ring, and discover and eliminate hidden dangers in time; when the vibration of the pump is found to be abnormal after starting, it should be decisively analyzed for cavitation phenomenon, whether the impeller is balanced, whether the pump shaft and the motor shaft are concentric or whether the shaft has been deformed, and then take corresponding measures.

5. Prevent leakage of fire pump seals

A small leakage of the centrifugal fire pump will generally not cause an accident, but it will affect the supply efficiency of fire fighting water or foam. Therefore, the fire pump with packing seal should be used to strengthen the inspection of sealing packing;

If it is found that the seal is not tight, the packing should be replaced in time to prevent the fire pump from leaking during operation and affecting its performance.

The basis for fire pump selection should be based on the process flow, water supply and drainage requirements, and consider five aspects, namely, liquid delivery volume, device lift, liquid properties, pipeline layout, and operating conditions.
1. The head required by the installation system is another important performance data for the selection of fire pumps. Generally, the head needs to be enlarged by 5%-10% to select the type.

2. The flow rate is one of the important performance data for selecting a fire pump, which is directly related to the production capacity and delivery capacity of the entire device.

3. The pipeline layout conditions of the device system refer to some data such as the height of the liquid delivery, the distance of the liquid delivery, the direction of the liquid delivery, the lowest liquid level on the suction side, the highest liquid level on the discharge side, etc., as well as the pipe specifications and their length, material, pipe fitting specifications, and quantity etc., in order to carry out the calculation of the comb head and the check of NPSH.

4. Liquid properties, including the name of the liquid medium, physical properties, chemical properties and other properties. Physical properties include temperature c density d, viscosity u, solid particle diameter and gas content in the medium, etc., which relate to the head of the system, effective gas Calculation of corrosion residue and suitable pump type: Chemical properties mainly refer to the chemical corrosion and toxicity of the liquid medium, which is an important basis for selecting the pump material and the type of shaft seal.

5. There are many operating conditions, such as liquid operation T, saturated steam force P, suction side pressure PS (absolute), discharge side container pressure PZ, altitude, ambient temperature, whether the operation is intermittent or continuous, and the position of the fire pump is Fixed or removable.