A company had a press used for forming steel bumpers for large trucks. The circuit was designed with a logic-type prefill valve. This valve was used to bypass the cylinder’s retraction flow of 290 gpm back to tank. It also featured a low-pressure closing spring to reduce any vacuum on extension. The 4-way directional valve only had to be sized to handle 55 gpm to retract the cylinder and provide tonnage after the ram encountered the steel plate.
While running production, the ram started to stutter badly on extension but still ran smoothly on retraction.
Can you identify what was the problem? We welcome responses of all kinds directly to Robert Sheaf at firstname.lastname@example.org or to email@example.com. The solution will be provided in conjunction with our December 2023 issue.
Filed Under: Components Oil Coolers, Valves & Manifolds