Vlier S55N Threaded Spring Plunger 1/4-20 Steel Locking

Product Description

The VLIER S55N is a standard threaded spring plunger designed to provide controlled, repeatable positioning force in mechanical assemblies, jigs, fixtures, and tooling applications. The S55N features a 1/4-20 thread with a 1 inch thread length and a steel body, making it well suited for industrial environments that demand durability. The plunger nose is also steel, with a minimum diameter of 0.117 inches and a maximum of 0.118 inches. Initial end force is 1 pound, and final end force is 4 pounds, giving technicians a predictable engagement feel. A locking element is included to secure the plunger in its threaded bore once adjusted to the correct depth.

This spring plunger is commonly installed in machined holes and tapped bores in workholding fixtures, assembly jigs, tooling plates, and light mechanical indexing applications. The 3/16 inch projection provides enough travel for positive part location or detent functions without excessive protrusion. It is appropriate for both OEM assembly and maintenance replacement situations where a standard 1/4-20 threaded plunger with a locking feature is required. Machinists, tool-and-die technicians, and mechanical assemblers are the typical installers.

Key Features

• 1/4-20 thread size with 1 inch thread length for broad fixture compatibility
• Steel body and steel nose for durability in industrial environments
• Locking element secures plunger depth after adjustment
• 1 pound initial end force and 4 pound final end force for predictable engagement
• 3/16 inch plunger projection in standard length configuration
• Plunger diameter range of 0.117 to 0.118 inches for precise fitment

Compatibility

Designed as an OEM-style replacement or direct-installation threaded spring plunger for any application requiring a standard 1/4-20 threaded bore with a locking-style plunger element.

Installation Notes

Install into a properly tapped 1/4-20 threaded bore using a hex key or flat-blade tool compatible with the plunger body drive feature. Ensure the mating bore is clean and free of debris before threading in the plunger. Engage the locking element only after the plunger has been adjusted to the correct projection depth. Always power down or de-energize any machine or fixture before servicing installed plungers.