Analysis of internal leakage performance of spool valve based on size chain and part size distribution

In spool valves, there is a fit gap between spool and sleeve, and the spool valve internal leakage is inevitable. For the problem of excessive leakage after assembly of qualified parts, taking a certain type of jet pipe servo valve as an example, and the probability density curve of the leakage through mathematical derivation by establishing the dimension chain about the fit gap and combining with the probability distribution of the part dimensions is reached. Simulation of internal leakage of spool with different fit gaps using ansys fluent, combined with the different distribution laws of the component rings in the dimension chain, the probability density curve plot of the fit gap and the probability density distribution image of its leakage are derived.