Machining method for sealing tape of valve seat ring of cylinder cover

Abstract

The invention discloses a machining method for a sealing tape of a valve seat ring of a cylinder cover. The method comprises the steps: firstly roughly machining the bottom surface of the cylinder cover; roughly machining a positioning pin hole on the bottom surface of the cylinder cover; taking the positioning pin hole roughly machined on the bottom surface as reference to machine a closed plug hole on the cylinder cover as middle reference; taking the closed plug hole as the machining reference to finely machine a valve guide pipe bottom hole, a valve seat ring bottom hole, a bottom-surface positioning pin hole and the bottom surface of the cylinder cover on the same set of fixture of the same equipment to the final sizes; pressing the valve guide pipe and the valve seat ring; and finally taking the bottom-surface positioning pin hole and the bottom surface of the cylinder cover as the machining reference to machine an inner hole of the valve guide pipe and the sealing tape of an inner hole of the valve seat ring. The bottom holes of the inner hole of the valve guide pipe and the sealing tape of the inner hole of the valve seat ring are machined at the same time by using the machining references, the allowance for continued machining is uniform, and the coaxiality of the sealing tape of the valve seat ring relative to the inner hole of the valve guide pipe meets the process requirements.

Description

technical field [0001] The invention relates to the field of diesel engines, in particular to a processing method for a cylinder head valve seat ring sealing tape. Background technique [0002] Such as figure 1 As shown, the valve 4 is an integral part of the combustion chamber of the diesel engine, and is installed in the valve guide 2 of the cylinder head 3. The head of the valve 4 cooperates with the valve seat 1 to control the opening and closing of the passage of gas entering and exiting the combustion chamber. The valve 4 has to bear great alternating and impact loads as well as the erosion and corrosion of high-temperature and high-speed gas during work. The sealing requirements between the valve 4 and the valve seat 1 are very high. The processing of the annular valve seat ring sealing band 11 of the seat ring 1 becomes an important and difficult point in the processing of the cylinder head 3. Usually, the processing technology of the valve seat ring sealing band 11...

AI Technical Summary

Problems solved by technology

[0008] The disadvantage of the existing processing method is that when the valve guide bottom hole 22 and the valve seat ring bottom hole 12 are processed in step three, since the bottom surface 31 of the cylinder head and the positioning pin hole are not processed on the same fixture and the same equipment, it is impossible to guarantee the same. The positions of each conduit bottom hole 22 and valve seat ring bottom hole 12 on the cylinder head relative to the positioning pin hole on the bottom surface of the positioning reference are theoretical values, which always have a certain deviation and are difficult to control; After circle 1, when the valve guide inner hole 21 and seat ring inner hole sealing tape 11 are processed based on the positioning pin hole on the bottom surface according to the theoretical position designed on the drawing, the machining allowance is uneven, which may easily lead to the sealing of the processed seat ring. The circular runout of belt 11 relative to the inner hole 21 of the valve guide does not meet the requirements, that is, the coaxiality of the sealing belt 11 of the valve seat ring relative to the inner hole 21 of the guide does not meet the process requirements, which affects the operation of the valve 4 and further affects the performance of the diesel engine

Images