How to exclude the oil injection phenomenon of Cummins generator set

When a Cummins generator set is working, the exhaust pipe exhausts the exhaust gas to the outside while the "spray" oil phenomenon occurs. The generator set is an in-line pump 6-cylinder electronically controlled diesel engine. After the test start, the engine is controlled by the electronic control system to idle for 5 seconds before entering the working speed mode of 15r/mm. There is no abnormal sound in the engine during work, and the exhaust emissions are normal. Based on the inspection and maintenance process, the author uses the analysis method to find out the cause of the failure, so as to provide a reference for the maintenance of the engine unit and ensure the maintenance quality.

Fault analysis of exhaust gas turbocharger

First of all, the exhaust gas turbocharger of Cummins generator set is removed, and it is found that there is no oil trace inside the air intake end and the outlet port of the supercharger, but the outer edge of the impeller is worn, and the exhaust gas into the turbine port has no oil trace, and the outlet port has oil trace. Then, remove the exhaust manifold and observe the exhaust valve head without accumulating carbon. Finally, the intake manifold was removed to observe the intake valve head, no oil traces and accumulation of carbon, and the engine 1 cylinder cover was removed to find no wear on the cylinder liner.

Exhaust gas turbocharger mechanism

At present, the construction machinery engine is equipped with the exhaust gas turbocharger, which uses the exhaust energy from the engine to drive the turbine and drive the compressor coaxial with the turbine to rotate at a high speed, compresses the air filtered by the air filter, and pressurizes the air into the engine cylinder, which can increase the power by 30%, 50%, and reduce the fuel consumption by about 5%. Reducing the emission of CO, HC, CL particles and other harmful substances in the exhaust gas is conducive to improving the dynamic performance, economic performance and emission quality of the whole machine.

Jiangsu Meao Power Technology Co., Ltd. is an important manufacturer of diesel generators. The company mainly manufactures and sells diesel generator sets with power of 3-3000kW, mobile power station of 24-600kW, Marine emergency diesel generator set of 24-800kW, gas generator set, heavy oil generator set and all kinds of imported series, special series (trailer, static speaker, mobile lighthouse, container, etc.) diesel generator At the same time, we are engaged in generator set maintenance and after-sale service of generator set accessories.