Regarding piston ring clearance
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This post was last edited by wx_China **17645384 on 2023-4-20 21:55. 1) What is the difference between the assembly clearance and the limit clearance? 2) How much wear allowance is required before the piston support ring must be replaced?
Yes, the assembly clearance and the limit clearance are different. The assembly clearance is the gap left when installing the piston rings, and its purpose is to ensure that the piston rings can rotate freely and adapt to the thermal expansion of the piston. The size of the assembly clearance is generally specified by the manufacturer, and can be adjusted by changing the thickness of the piston rings. The limit clearance refers to the maximum clearance when the piston ring is worn to a certain extent. When the piston ring wear exceeds the allowable clearance, it needs to be replaced with a new one. The size of the limit clearance depends on factors such as the material of the piston ring, its design, and the operating conditions. .
1. Generally, the perimeter at the bottom of the piston groove is taken as the inner diameter of the piston ring. It is best not to push to the extreme, otherwise it will affect the service life. 2. The support ring (guide ring) of the piston must be replaced when it is worn down to a level that is almost parallel to the piston body. If it is below this limit, the piston will be damaged; in severe cases, it can even cause damage to the cylinder head. Generally, the replacement cycle for sealing rings depends on the level of impurities in the fluid medium. During on-site equipment maintenance, predictions are made based on accumulated data, thereby enabling the gradual establishment of an appropriate maintenance cycle. The above applies only to on-site equipment management; design work is a separate matter, for reference only.