How does the diesel generator cooling system work?
The composition of the water cooling system of the portable diesel generator sets: the main components of the diesel generator that need to be cooled, including: the heat dissipation medium of the cylinder liner, the cylinder head, the lubricating oil, etc., are directly cooled by water, which is called a water-cooled diesel generator. A water-cooled diesel engine requires a very complex cooling water circulation system (such as: water tank, water pipe, fan, radiator, water pump and temperature controller, etc.).
Air cooling system for portable diesel generator sets. The air cooling system uses high-speed air flow to blow directly over the outer surface of the cylinder head and cylinder block, and dissipates the heat from the inside of the cylinder to the atmosphere to ensure that the generator works within the most favorable temperature range. Diesel generator cylinders and cylinder heads are made of aluminum alloy with good heat transfer. In order to increase the thermal area, each cylinder is generally manufactured separately, and many evenly arranged radiating fins are distributed on the surface of the cylinder and cylinder head to increase the heat dissipation area. Using the high-speed air flow when the engine is running, the heat is blown into the atmosphere. Due to the large power of diesel generators, more heat needs to be cooled, and axial fans with large power and flow are often used to strengthen the cooling of diesel engines. In order to effectively utilize the air flow and ensure uniform cooling of each cylinder, a shroud, a shunt plate and a cylinder liner baffle are installed on the diesel generator. Compared with the water cooling system, the air cooling system has the advantages of simple structure, light weight, few failures, and no special maintenance. However, due to the high material quality requirements, the cooling is not uniform enough, and the working noise is large, it is rarely used at present. It is widely used in construction machinery and agricultural equipment.
Why carry out AC dummy load for diesel generator set inspection and maintenance?
As an emergency backup power supply after a power outage, the diesel generator set is in a standby state most of the time. Once the power outage or mains failure occurs, the standby diesel generator set plays a vital role. However, we often find out that there is a problem with the performance of the diesel generator set after the power failure occurs, which shows that many users do not pay enough attention to the knowledge of the AC dummy load for the detection and maintenance of the diesel generator set.
Check the diesel generator set. By detecting the AC dummy load for maintenance of the diesel generator set, the unbalanced load capacity of the diesel generator set can be detected to ensure the steady-state voltage regulation rate, steady-state frequency regulation rate, transient voltage regulation frequency, voltage recovery time, and transient frequency. Adjustment rate, frequency recovery time, continuous operation detection of diesel generator sets.
Check UPS. Output voltage unbalance, output voltage regulation accuracy, overload capacity, dynamic voltage transient range, mains battery switching time, backup time, bypass inverter switching time.
Main functions of AC dummy load for inspection and maintenance of portable diesel generator sets
- Query function. Query diesel generator sets to retrieve abnormal records and query diesel generator set detection data.
- Online communication. The detector can be connected with the host computer through the RS232/RS485 interface.
- Intelligent control and data processing functions
1) Data dump: After the detection, the collected data can be dumped to the U disk;
2) Online monitoring of the electrical parameters of the device under test;
3) Function of data processing software: The data processing software is used together with the detector. The detection parameters can be set to analyze and process the electrical parameters, operating status and abnormal records detected by the detector; intelligent query, display and print charts.
4) Automatic detection can be achieved by setting parameters of the detection equipment.
Products of the same model can be connected in parallel. The device is equipped with an RS485 digital parallel interface, which is uniformly controlled by the host and records the detection process.
Shutdown protection function. The AC dummy load for diesel generator set inspection and maintenance is based on the general AC dummy load and load box, and an intelligent control system is added, which can perform protection settings such as phase loss, overvoltage and undervoltage, etc. Once the parameters detected by the equipment exceed the set parameters, the device will sound an alarm and automatically shut down for protection.
How many sensors are there in diesel generator sets?
There are three kinds of sensors in diesel generator sets: oil pressure sensor, temperature sensor and speed sensor. What is a diesel generator set oil pressure sensor?
The oil pressure sensor literally monitors the amount of lubricating oil in the diesel generator set. If the oil pressure of the diesel generator set is too low, then we need to check whether the oil pressure sensor is faulty. Diesel engines are lubricated by lubricating oil. Once the lubricating oil pressure is too low, various components of the diesel generator set will produce friction, causing component failures and heat denaturation and other failures, and serious damage to the diesel engine. Therefore, we should also regularly check whether the oil pressure sensor is normal when using the diesel generator set.
What are the methods of fuel supply and exhaust gas for portable diesel generator sets?
If you don’t have the wrench to loosen the joint in the pipeline, you can press the hand pump repeatedly until the pressure of the low-pressure oil circuit from the fuel pump to the fuel injection pump is high enough, and the fuel flows from the relief valve into the fuel return pipeline. The gas will be discharged from the overflow valve.
If the trailer generator does not have a suitable screwdriver or wrench to open the bleed screw on the fuel injection pump during driving, you can unscrew the hand fuel pump first, then loosen any pipe joint from the diesel filter to the fuel injection pump, and then Press the hand oil pump repeatedly to discharge smooth and air-free oil flow from the joint, then tighten the joint while pressing the hand oil pump, and then press the hand oil pump back to its original position.
Use a screwdriver or wrench to unscrew any of the exhaust screws on the upper ends of the fuel injection pump for several turns, and press the manual fuel pump by hand until the discharged diesel oil is continuous, smooth and without bubbles, and a “squeak” sound is heard. Then tighten the bleed screw, and manually press the oil pump back to its original position.
If you need to remove the air in the oil circuit on the way, you can first loosen the bleed screw on the fuel injection pump or loosen any joint between the diesel filter and the fuel injection pump, and then drive the mechanical fuel pump by starting. The leak point will spray smooth and bubble-free fuel, and then you can tighten the above leak point you loosened.
How to debug the diesel generator governor?
How to check and adjust the speed stability of diesel generator governor? The diesel generator governor is a device that automatically adjusts the fuel supply of the fuel injection pump. It can automatically adjust the fuel supply of the fuel injection pump according to the change of the external load of the diesel generator, so that the diesel generator runs at a relatively stable speed, so as to ensure that the diesel generator neither overspeed nor idling. cause downtime. So how to check and adjust the stability of diesel generator governor speed?
Method 1: Set the joystick at the calibrated speed position, and slowly increase the speed of the camshaft. When the fuel supply of the fuel injection pump begins to decrease (that is, the starting point of the speeder), immediately keep the speed of the camshaft unchanged, and then carefully adjust the speed of the camshaft. Observe the adjusting gear and adjusting gear rod, and there must be no swimming phenomenon.
Method 2: When the speed of the camshaft is 400r/min, 250r/min or any other speed, use the method of changing the position of the joystick to make the adjusting gear rod in the position of various oil supply amounts. At this time, check the adjusting gear and adjust the Gear rod, so that there is no swimming phenomenon.
Method 3: When the diesel engine is unstable at low speed, the low-speed stabilizer can be slowly rotated until the speed is stable and then fixed. The factory diesel engine has been adjusted. If it is not necessary, the user should not pull it. Adjustment is only necessary after dismantling and repairing. Note that the low-speed stabilizer should not be screwed in too much, so as to avoid the minimum stable rotation speed being too high.
Installation specification for smoke pipe of diesel generator set
- In order to prevent the condensate from flowing back into the unit, the horizontal layout smoke pipe should have a slope, and the low end should be far away from the engine; in the muffler and any other pipeline parts with condensed water dripping, such as the vertical turning of the smoke pipe, it should be set drain.
- When the smoke pipe passes through the flammable roof, wall or partition, an insulating sleeve and a wall jacket should be added.
- When conditions permit, most of the smoke pipes should be arranged outside the machine room to reduce radiant heat; all indoor smoke pipes should be equipped with heat insulation jackets. If limited by the installation conditions, when the muffler and the rest of the pipeline must be placed indoors, the entire pipeline should be wrapped and insulated with a 50 mm thick high-density thermal insulation material and an aluminum sheath.
- Thermal expansion should be allowed when the pipeline support is fixed.
Finally, it should be noted that the end of the exhaust pipe should be able to avoid rainwater dripping. The smoke pipe can be extended horizontally, the outlet can be repaired or the rain cap can be installed.
What is the function of the water tank of the portable diesel generator sets?
Everyone knows that the main function is to reduce the water temperature. If the water temperature cannot be lowered for a long time, the diesel generator will be considered bad.
The water tank of the diesel generator set is an important part of the water-cooled engine. As an important component of the cooling circuit of the water-cooled engine, it can absorb the heat of the cylinder block and prevent the engine from overheating.
Due to the large specific heat capacity of water, the temperature rise after absorbing the heat of the cylinder block is not much, so the heat of the engine passes through the liquid circuit of cooling water, uses water as a heat carrier to conduct heat, and then passes through a large area of radiating fins for convection. way to dissipate heat to maintain the proper working temperature of the diesel generator set engine.
When the water temperature of the diesel generator set engine is high, the water pump is repeatedly circulated to reduce the temperature of the engine. ) To achieve the purpose of protecting the engine, if the water temperature is too low in winter, the water circulation will be stopped at this time to prevent the engine temperature of the diesel generator set from being too low.