Vlier PR500 Locking Pull Ring Plunger 1/2-13 Steel

Product Description

The VLIER PR500 is a locking pull ring plunger designed for precision indexing and positioning applications in industrial assemblies. Threaded at 1/2-13 with a 1.4-inch thread length, this plunger features a 5/16-inch (0.312 inch) plunger diameter and delivers an initial end force of 2.5 pounds building to a final end force of 5 pounds. Constructed from steel for durability under repeated actuation cycles, the PR500 uses a pull ring locking mechanism that holds the plunger in the retracted position until deliberately released. It is installed by machinists, toolmakers, and maintenance technicians working with fixtures, jigs, and machine components.

The PR500 is suited for use in manufacturing fixtures, assembly jigs, machine tool components, and industrial equipment where repeatable positioning and secure plunger lockout are required. The pull ring design allows the operator to retract and lock the plunger without tools, making it practical for applications requiring frequent manual adjustment. With a 2-inch body length and 1.26-inch ring diameter, it fits standard threaded bores in steel and aluminum fixtures across a range of light-to-medium industrial settings.

Key Features

• Locking pull ring mechanism holds plunger retracted without tools
• 1/2-13 thread size with 1.4-inch thread length for secure installation in standard threaded bores
• Initial end force of 2.5 pounds progressing to 5 pounds final end force for reliable indexing
• Steel construction for durability in industrial environments
• 0.5-inch plunger projection provides positive engagement with mating holes or slots
• Compact 2-inch body length suits tight fixture envelopes

Compatibility

Designed as an OEM-style replacement or direct installation component for industrial fixtures, jigs, and positioning assemblies that accept a 1/2-13 threaded spring plunger with locking pull ring actuation.

Installation Notes

Installation is performed by machinists or maintenance technicians using a wrench on the hex head. De-energize or lock out any associated machinery before servicing fixtures containing this plunger. Apply thread-locking compound or torque to the specified fixture design requirements - do not overtighten, as this may restrict plunger travel or damage the locking ring. Verify plunger projection and end force meet the positioning requirements of the application before final assembly.