Views: 121 Author: Site Editor Publish Time: 2021-06-08 Origin: Site
Regular maintenance of diesel generators, such as 4 stroke 6 cylinder diesel engine, is an important measure to ensure the safe operation of equipment; it is an effective means to restore the technical performance of equipment, eliminate faults and eliminate hidden dangers, and extend the service life of equipment.
1. Equipment maintenance can not correctly judge and analyze the fault, blindly dismantle and unload.
Some maintenance personnel are unclear about the structure and principle of the equipment machinery (such as new staionary high speed 6 cylinder diesel engine), do not carefully analyze the cause of the failure, and cannot accurately determine the location of the failure. They blindly dismantled and unloaded the equipment. As a result, not only the original fault was not eliminated, but also new problems appeared due to poor maintenance skills and processes. For example, there was a failure of a 227KW 4 stroke diesel engine with insufficient power and mechanical failure. The maintenance personnel disassembled the PT fuel injection pump and fuel injector, and did not find the cause of the failure. The test was replaced by one fuel injection pump, and the failure remained. The final inspection failure is caused by impurities and excessive moisture in the diesel used. The disassembly resulted in a significant decrease in the performance of the PT fuel injection pump and insufficient power of the diesel generator.
Therefore, when the machine fails, it must be tested by the testing equipment. If there is no detection equipment, the traditional fault judgment methods and means such as "ask, see, check, and test", and the structure and working principle of the equipment can be combined to determine the most likely fault location. When judging equipment failures, the "exclusion method" and "comparison method" are commonly used, in order from simple to complex, first appearance and then interior, first assembly and then components, avoiding "blind disassembly and unloading".
2. The phenomenon of blindly replacing parts exists to varying degrees.
Considering the number of cylinders, speed and power of the diesel engine, it is relatively difficult to judge and eliminate equipment failures. For example, the specifications of the high speed 12 cylinder diesel engine and 6 cylinder 4 stroke diesel engine are different, and they are not handled in the same way when there is a situation. Some maintenance personnel have always adopted the method of replacement test, regardless of the large or small parts, as long as they are considered to be the parts that caused the failure, one by one replacement test. As a result, not only the fault was not eliminated, but the parts that should not be replaced were randomly replaced, which increased the maintenance cost. Some faulty parts can be restored to their technical performance through repairs, such as generators, air compressors, blowers, burners, gear oil pumps, etc., which can be repaired without complicated repair processes. During maintenance, the cause and location of the fault should be carefully analyzed and judged according to the fault phenomenon. The repairable parts should be repaired to restore the technical performance, and the practice of blindly replacing parts should be eliminated.
3. There are many phenomena that do not pay attention to detecting the fit clearance of parts.
In the maintenance of common diesel generators, the clearance between the piston and the cylinder sleeve, the "three clearance" of the piston ring, the top clearance of the piston, the valve clearance, the plunger clearance, the brake shoe clearance, the meshing clearance between the main and driven gears, the axial and Radial clearance, clearance between valve stem and valve guide, etc., have strict requirements for various models, and must be measured during maintenance, and parts that do not meet the clearance requirements must be adjusted or replaced.
In actual maintenance work, there are many phenomena of blindly assembling parts without measuring the fit clearance. This leads to early wear or ablation of bearings, burning of diesel generator oil, difficulty in starting or deflagration, broken piston rings, impact of machine parts, oil leakage, air leakage and other failures. Sometimes, due to improper clearance of parts, serious mechanical damage may occur.
4. When the equipment is assembled, the parts are sometimes reversed.
When servicing equipment, some parts are assembled with strict directional requirements; only proper installation can ensure the normal operation of parts. The external features of some parts are not obvious, and both positive and negative can be installed. In actual work, it is often reversed, resulting in early damage to parts, machinery not working properly, and equipment damage accidents.
5. The maintenance method is not formal, and "fixing the symptoms but not the cause" is still the habit of some maintenance organizations.
In the maintenance of equipment, some maintenance personnel do not take the correct maintenance method, and think that emergency measures are omnipotent, and replace "maintenance" with "emergency". An example is the frequently encountered "replacement by welding". Some parts can be repaired, but some maintenance personnel often save time, but often use the "welding dead" method; in order to make the diesel generator "vigorous", artificially increase the fuel supply of the fuel injection pump and increase the fuel injection of the injector pressure. These irregular maintenance methods can only be used for emergency, but cannot be used for a long time. The cause of the failure must be fundamentally detected, and a formal maintenance method should be adopted to eliminate the failure, which should be brought to the attention of the maintenance personnel.