Xinzheng Industrial Park,Qingyuan West Street,Weifang Economic Development Zone,Shandong,China
diesel generator  +86 15905360231    diesel generator
CURRENT LOCATION:HOME > Steyr generator > The compression ratio of diesel engine can not be ignored >
The compression ratio of diesel engine can not be ignored
Update:2017-02-27 Tags:the

Compression ratio of the total volume and the volume ratio of the combustion chamber for diesel alternator generatorengine cylinder, it changes, not only affects the performance and fuel economy of diesel engine, and affect its startup performance. Every diesel engine when the design rules for a the best compression ratio, but in use, because of the influence of the various relevant factors, the compression ratio tends to reduce. Now will be the main reason for the lower compression ratio and maintenance should be paid attention to some problems in the process of the paper are as follows:

One, the piston position at the end of the compression on the low side

(1) related parts fit clearance is too large. When the crankshaft main bearing and main journal, connecting rod bearing and connecting rod journal, liner and piston pin and piston pin and pin hole fit clearance is too large, in the process of compression, tend to cause the actual location of the piston top dead center down, resulting in a compression ratio. As a result, the repair should be the fit clearance control in the range of allowable values.

(2)Poor diction related parts deformation or main dimensions. When grinding crankshaft connecting rod journal, for example, did not adjust eccentricity, make after grinding crankshaft rotating radius; Connecting rod bending, to make the connecting rod, small end hole center distance shortened; Piston pin hole reaming partial, the piston pin hole centerline to the piston top plane distance. These factors, can create the position of the piston during compression on the check point down, compression ratio decreased. As a result, the repair shall comply with the specifications, ensure the quality of repair. Don't forget to check in to change at the same time, don't change or wrong with unqualified parts. When to change, should check the contents are: the radius of gyration of the crankshaft, connecting rod, small end hole center distance, the piston pin hole centerline to the piston top plane distance, the body on the plane and main bearing hole of the distance between the center line.

Second, the combustion chamber volume is larger

(1) the valve and valve seat serious wear and tear, the sink of the valve is too large (or even more than limit value). At this point should replace valve and seat.

(2)Cylinder cushion thickness exceed the design requirements, or to artificially increase the cylinder gasket thickness. Cylinder pad should be replaced to meet the requirements at this time.

(3) piston at the top of the pit (part of the combustion chamber) ablation defects, or change the wrong parts, pit volume is too large (or water injection correlation method to check). At this time with qualified piston should be replaced.

(4) the swirl chamber on the cylinder head loss, or quality is unqualified, the volume is too large (or water injection correlation method to check). A qualified cylinder head should be replaced at this time.

It is worth mentioning that in the above of the many factors led to the decrease of the compression ratio, often a single factor's influence is not big, but the superposition of multiple factors accumulation on the influence of compression ratio is big. As mentioned above, in order to make the diesel engine's compression ratio can be controlled within the prescribed scope, is the key to improve the quality of repair, to do a good job of repair, measurement and matching parts, within the scope of the technical requirements to allow, as far as possible choose small fitting clearance. When the engine start difficult, power decline, fuel consumption increase cylinder sealing, with gas and oil are normal, seems to find out the cause of the problem, don't neglect to examine the compression ratio.

Copyright Weifang Huaquan Power Machinery Co.,Ltd
Powered by Huaquan