Sliding vs. Locking Ring: Which Non-Return Valve Is Right for You?

摘要

One of the most important of the hundreds of details involved in the injection molding process is the non-return valve, or check ring. There are various versions: three-piece, four-piece, full-flow, ball-check, etc. In more recent years, sliding-and locking-ring types have been added to the list. Which one is right for you? They all have their issues, and the focus here is on the issues between sliding-vs. locking-ring types. The terms "non-return valve" and "check ring" will be used interchangeably, for both terms are common in the injection molding community. First, what is the purpose of the check ring and how does it work?