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Gas generator set fault prevention measures

August 03, 2022
1 Common faults and causes of diesel generator set for sale
1.1 abnormal water temperature of the cylinder liner
The manifestation sign of abnormal cylinder liner water temperature fault is the ECM control module or the upper computer reporting the cylinder liner water temperature alarm signal during the operation of the diesel generator set for sale, mainly including "high cylinder liner water temperature" and "low cylinder liner water temperature" 2 kinds of signals, and after the unit issued a warning The alarm signal is automatically switched to shutdown state for a period of time after the warning is issued. Among them, the causes of the high cylinder liner water temperature fault include the cooling water pipeline is blocked by scale; the cooling fan motor is damaged or stopped running; the water pipeline joint part is leaking; the temperature sensor is faulty or the monitoring accuracy is declining; the thermostat is faulty and failed; the cooling water level is too low for a long time without refilling cooling water, which affects the cooling effect. And the causes of low cylinder liner water temperature fault include heater failure failure, temperature sensor failure, failure to close the thermostat device in time, circuit failure, etc [1].
1.2 Starting difficulty
The manifestation signs of difficult starting fault are the absence of engine speed after the unit start command and energized operation, and the inability to start the equipment with stable voltage and the presence of coiling speed. The main reasons for this fault include cable disconnection, incoming air pressure value does not reach the starting standard, starter motor device failure, battery capacity is not enough, the spark plug is damp or end hole blockage, battery voltage can not drive the motor to start (air motor for compressed air, low pressure can not drive the motor), high voltage package short circuit and starting circuit is not working. For example, when the spark plug is in a wet state, it cannot effectively introduce high voltage electricity into the combustion chamber to produce a spark, resulting in the ignition system failure and the motor cannot start normally.
1.3 Abnormal exhaust gas temperature
Abnormal exhaust gas temperature failure is indicated by the ECM control module reporting the fault code "exhaust temperature too low" or "exhaust temperature too high", which indicates that the real-time exhaust temperature ofdiesel generator set for sale exceeds the safety threshold during operation and is out of control. Among them, the reasons for the high exhaust temperature fault include excessive deposits on the top of the cylinder piston and valve seat, the exhaust resistance value exceeds the allowed upper limit, the unit is in full load operation or overload operation for a long time, and the exhaust pipe is blocked. The causes of low temperature exhaust failure include abnormal condition of ignition system devices such as spark plugs and ignition harness, failure of temperature sensor and matching harness, and low real time cylinder pressure value.
1.4 burst
The manifestation sign of burst fault is that the control module reports "single cylinder burst fault" signal, or the corresponding fault code pops up on the unit display and system operation interface, and the unit will switch to the shutdown state after the burst fault occurs. The causes of the fault include high real time inlet temperature, the unit is not in 100% correction factor operation, excessive carbon deposits in the cylinder combustion chamber, excessive ignition advance angle, failure of the detonation sensor, cooling water temperature exceeds the standard, and runaway air-fuel ratio. For example, due to excessive ignition advance angle, during the operation of the unit, the gas is ignited before the piston reaches the upper stop, resulting in excessive pressure values during the compression stroke of the piston, which interferes with the piston stroke under the action of pressure values, and eventually a detonation fault [2].
1.5 load belt is not full or swing
Load band underfill and oscillation faults manifest themselves as the actual load does not reach this standard after the unit is ordered to run at 100% load, or the load oscillation exceeds ±50 kW range when the throttle is adjusted to the maximum. The main causes of this fault include stuck throttle and metering valve, thermal value correction factor not maintained at 100%, poor exhaust blockage and poor air intake, power sensor failure, single or multi-cylinder non-ignition due to non-compliant exhaust temperature, excessive intake manifold differential pressure and abnormal combustion filter [3].
2 gas generator set failure problems of effective preventive measures
2.1 Do a good job of daily inspection and maintenance work
In order to maintain the good operating conditions of diesel generator set for sale, timely detection of fault problems and abnormal operating conditions, it is necessary to establish a long-term maintenance and inspection system, do a good job of daily inspection and maintenance, staff strictly follow the requirements of the maintenance manual of gas generator sets provided by the manufacturer, check the operating conditions of the units, clean the dust and stains on the surface of the casing, replace the aging and wear parts, record the operating parameters of the units, compile the inspection log and upload the maintenance manual. parameters, compile inspection logs and report problems. In general, the inspection and maintenance of gas generator sets are to visually observe the surface cleanliness and operating conditions of the set, tighten the fasteners such as the foot nuts and flywheel screws, clean the surface dust and stains, measure whether the intake/exhaust valve clearance values are up to standard, turn the crankshaft with the coiling device to listen to the sound of each cylinder base part and judge the crankshaft rotation, and shake the crankshaft after closing the decompression mechanism to check Check the air leakage of cylinders. Next, check the gas tightness of all piping and the interface of gas, coolant, exhaust gas, lubricating oil and intake air, check the flexibility of the speed adjustment control lever, test the function of the monitoring device, remote control and shutdown device, add coolant and additives through the filling connector, discharge the air in the coolant holding chamber through the exhaust pipe during the operation of the cooling pump, and repeat the check of the coolant level. Again, add lubricating oil in the gas generator set, use the dipstick to measure the oil level, replenish the oil with the TEM system, and in case the oil level is too low, the monitoring system will issue a command not to allow starting and shutting down the engine. Finally, before the engine starts, carry out pre-lubrication operation, start the pre-lubrication pump in advance, and then start the engine after the pre-lubrication process is completely finished.
2.2 Organize preventive maintenance
According to the requirements of the gas generator set maintenance manual, regularly disassemble the gas generator set into several parts, check the degree of aging and wear of each part item by item, clean the dust and oil on the surface of the parts, replace the parts with serious wear and distortion, apply anti-rust oil evenly on the surface of the parts, as well as replace the failed pump water seal, cylinder liner water temperature sensor, thermostat, starting motor and other devices. After making sure there are no errors, the parts are assembled into a complete gas diesel generator set for sale in order, and the installation, relative position and interval distance of each part are checked in detail, and the functional test is carried out with electricity to observe the operating status of the set under different working conditions. In addition, comprehensive analysis of the gas generator set's service life, historical operating conditions, failure rate and other factors, the implementation of a graded technical maintenance system, different levels of disassembly and maintenance content, process steps are different. While playing the ideal preventive maintenance effect, it also reduces the workload of unit maintenance and avoids disrupting the normal operation of diesel generator set for sale due to frequent dismantling and maintenance work. For example, using the accumulated working time as the grading standard, primary technical maintenance work is carried out after the accumulated working time of gas generator sets reaches 100h, secondary technical maintenance work is carried out after the accumulated working time of the sets reaches 500h, and tertiary technical maintenance work is carried out after the accumulated working time of the sets reaches 1000h or 1500h [4].
2.3 Adopting diversified fault diagnosis methods
Multiple fault diagnosis methods such as partial stop method, comparison method, instrument diagnosis method, disassembly and inspection method and trial method are used to break through the limitations of a single diagnosis method. Among them, the partial stop method is to stop the operation of one or more devices during the operation of the unit and observe whether the operating condition of the unit changes or the external signs of the fault disappear, so as to determine the general location of the fault. The comparison method is to directly replace the thermostat, temperature (speed) sensor, starter motor, battery and other components and devices that may be faulty, and compare the operation of the unit before and after device replacement. Instrument diagnosis method is to use pressure gauge, combustion analyzer, oil detector, vibration detector and other instruments and equipment to measure the operating parameters of gas generator set, compare the measured value with the corresponding parameter index, and determine the type of fault and lock the fault point according to the deviation of the two. Iron content exceeds the standard when the probability of excessive wear cylinder liner failure, in aluminum content exceeds the standard when the probability of piston pull on the failure. Disassembly method is applicable to the conventional diagnosis method can not determine the type of fault, by the staff will power off, stop the gas generator set disassembled into a number of parts, check the operating conditions of each component, such as cylinder piston ring opening position, cylinder piston top deposits, cooling water lines, shock lines and plugs, etc., to determine the type of fault, lock all the fault points and find other hidden faults, this method The diagnostic efficiency is low, but the diagnostic accuracy is relatively high. The trial method is to make appropriate adjustments to the operating status and parameters of the gas generator set, and observe whether the overall and local working conditions of the set change before and after the adjustment, so as to determine the type of fault [5].
2.4 Develop emergency maintenance plan for gas generator sets
For the fault of high cylinder liner water temperature, check the operation status of heat sink motor, thermostat, temperature sensor and electrical circuit in turn, replace the abnormal rotating fan motor, new thermostat and temperature sensor in time, and if everything is normal, adjust the operating load downward. As for the fault of low water temperature of cylinder liner, if the water temperature is so low that the unit cannot be started normally, check the heater, shutdown relay and temperature control switch device as a priority, replace the abnormal device or part of the accessories, and then, check the sensor, electrical circuit and thermostat in turn to see if there is any fault problem and replace the failed device and accessories. For the unit starting difficulty fault, check whether the battery charge is sufficient, charge the battery or replace the fully charged battery, and check and tighten the battery line and plug. If the intermediate relay fails or the starter button has poor contact with the starter circuit, replace the intermediate relay and starter button with new ones and deal with the poor contact of the starter circuit. For abnormal exhaust temperature fault, if the exhaust temperature of the unit is too low during operation, focus on checking whether the spark plug and high voltage package components are operating normally, replacing the new ignition harness if necessary, and taking the interchangeable wiring test method to test the exhaust temperature harness and sensor conditions, and troubleshooting or replacing the new device according to the test results. In the exhaust temperature exceeds the standard, focus on checking the exhaust pressure value, the pressure value exceeds the standard indicates that the exhaust system is blocked, unblock the blocked parts and adjust diesel generator set for sale load down to the rated value can be. For the explosion fault, the first measurement of the intake gas temperature value, if the intake gas temperature far exceeds the rated threshold, then in accordance with the gas temperature exceeds the standard fault to investigate, in turn, check the thermal value and the gas concentration is matched, the thermal correction coefficient, the sensor detection value is accurate, observe the cylinder and valve seat parts of the distribution of carbon and clean, measure the cylinder internal leakage, according to the results of the inspection, the thermal correction coefficient will be adjusted To 100%, replace the failed sensor and the leaking cylinder. In order to solve the problem of insufficient load and oscillation, we first checked whether the differential pressure of the intake manifold exceeded the rated value, and judged whether there were problems of stuck throttle, stuck bypass valve and zero point drift according to the inspection results, and took targeted measures such as moving throttle and tightening valve flap. After that, the operating conditions of exhaust pipeline and three-way valve are further checked, and the three-way valve is replaced and the blocked pipeline is unblocked when the pipeline is blocked and the load is swinging abnormally. Finally, check the condition of fuel and air filters and measure the differential pressure of gas, replace the blocked parts and new metering valve, and adjust the heat value correction coefficient to 100%.
2.5 Build gas generator set condition monitoring and fault diagnosis system
First of all, in terms of unit condition monitoring, with the powerful logic operation and data processing capability of the system, diesel generator set for sale unit condition prediction test is carried out periodically to simulate the operating conditions of the gas generator unit in a period of time in the future based on the historical operating data, fault maintenance reports, equipment operating life, the rate of various types of faults, and the fluctuation of parameters before and after faults. Based on the prediction results, the system helps the staff to find out the possible fault problems in advance, determine the type of fault, analyze the cause of the fault and take corresponding measures to avoid the fault by relying on the prediction report. Secondly, in terms of fault diagnosis, the system has a large number of self-test signals, so that when there are large fluctuations of parameters, parameter overruns, or excessive deviations between real-time parameters and expected values during the operation of the unit, the system will automatically send alarm signals and analyze the operating parameters of the unit before and after the abnormal conditions, so as to determine the type of fault, lock the location of the fault point, display the fault code on the operation interface and generate fault self-diagnosis report on the operation interface to facilitate the subsequent manual diagnosis and on-site maintenance [6].
2.6 Do a good job of operating environment management
The external environment is an important influencing factor of the operating status of diesel generator set for sale, and the poor environmental conditions will interfere with the operating status of the units, which is also the main cause of the recurrence of some fault problems. Therefore, in order to ensure the safe and stable operation of gas generator sets, we must do a good job in operating environment management to create a suitable and stable working environment for the sets. Firstly, the gas generator set workshop is strictly managed in accordance with the explosion-proof workshop, and corresponding explosion-proof measures are taken for lighting fixtures, switchgear, lines and other electric and electrical equipment to avoid electrical fires, such as line short circuits, insulation failure and release of heat with the formation of electric arcs. Secondly, regularly clean the workshop floor, walls and ceilings and other parts of the dust and debris, requiring a bright and spacious workshop environment, and install ventilation equipment to improve workshop conditions. Finally, install combustible gas alarm devices at multiple points in the workshop, desulfurization, dehydration and dust removal treatment for the gas used in advance, and make sure that the gas contains less than 0.25m3 of sulfur before putting the gas into use.
3 Conclusion
To sum up, in order to effectively meet the increasing reliability requirements of gas generating sets, and to avoid the frequent occurrence of various types of failure problems and interference with the operating conditions during the operation of the sets. The staff needs to pay great attention to the problem of gas generator set failure, comprehensively grasp the common failure problems and causes, implement the above-mentioned failure prevention measures, and develop a perfect equipment operation management mode and long-term maintenance system on its basis, so as to clear the obstacles encountered during the large-scale application and promotion of gas generator sets.

Hubei Junvoch Industrial & Trade Co., Ltd

Final Words

As a result, the pointers above are necessary when selecting the best diesel generator for an industrial or commercial application. It is essential to choose the appropriate diesel generator set to assist you in increasing the productivity of your business and the amount of revenue you make.

So, if you are involved in purchasing the best diesel generator of the greatest possible quality and performance, do not hesitate to contact us. Additionally, seeing how a generator works will provide you with a more satisfying overall experience. When buying a diesel generator for industrial or commercial use, there are several different aspects to consider. Consult with experts to learn more about the solution that is the best fit for the application you have in mind.