Vlier S56N Threaded Spring Plunger 5/16-18 Steel Locking

Product Description

The VLIER S56N is a standard threaded spring plunger designed for indexing, positioning, and light-duty holding applications in industrial assemblies. It features a 5/16-18 thread with a 1 inch thread length and a steel body construction. The plunger nose is also steel, offering durability in repeated-cycle environments. Initial end force is 3 pounds, with a final end force of 15 pounds, giving the installer a defined engagement feel. A locking element is incorporated into the body to secure the plunger in position after installation without the need for additional fasteners. Machinists, tool and die technicians, and precision assembly professionals are the primary installers of this component.

The S56N is suited for use in jigs, fixtures, tooling plates, and mechanical assemblies where a reliable spring-loaded positioning point is needed. The 3/16 inch plunger projection keeps the engagement profile low, making it appropriate for tight-clearance applications. Its standard plunger length type and threaded body allow direct installation into tapped holes in steel, aluminum, or similar materials. It is commonly used in OEM equipment builds and maintenance replacement scenarios on production and assembly equipment.

Key Features

• 5/16-18 thread size with 1 inch thread length for direct installation into standard tapped holes
• 3/16 inch plunger projection for low-profile engagement in tight-clearance assemblies
• 3 pound initial end force and 15 pound final end force for consistent, defined positioning feel
• Steel body and steel nose material for durability in high-cycle applications
• Integrated locking element secures the plunger body after installation without jam nuts or adhesives

Compatibility

Designed as an OEM-style replacement or new-installation spring plunger for industrial jigs, fixtures, tooling plates, and mechanical positioning assemblies using a 5/16-18 tapped hole.

Installation Notes

Installation is performed by machinists or assembly technicians using a standard hex wrench or spanner tool appropriate for the plunger body drive style. Ensure the receiving tapped hole is clean and free of debris before threading in the plunger. The locking element should be engaged after the plunger is set to final position to prevent back-out under vibration. Do not exceed the specified final end force rating by over-compressing the plunger during assembly.