Vlier PRM12 Locking Pull Ring Plunger M12x1.75 Steel

Product Description

The VLIER PRM12 is a steel locking pull ring plunger designed for precision indexing, positioning, and holding applications in mechanical assemblies. The pull ring allows manual retraction of the plunger without tools, and the locking feature holds the plunger in the retracted position until released. The M12x1.75 threaded body installs into tapped holes in machine frames, fixtures, jigs, and tooling plates. With a plunger diameter of 8mm and a thread length of 1.4 inches (35.56mm), this plunger delivers an initial end force of 11 N and a final end force of 22 N, making it suitable for light-duty positive location tasks.

The PRM12 is used in industrial and mechanical fabrication environments where repeatable positioning is required. Typical applications include workholding fixtures, assembly jigs, rotary tables, drawer indexing mechanisms, and machine tool accessories. The pull ring design allows a single technician to retract and lock the plunger without reaching behind a panel or using a secondary tool, which suits tight-clearance installations. Machinists, toolmakers, and mechanical maintenance technicians are the primary installers.

Key Features

• Locking pull ring retracts and holds plunger in the retracted position for hands-free operation
• M12x1.75 thread size with 1.4 inches (35.56mm) thread length for secure installation in standard tapped holes
• 8mm plunger diameter with 12.7mm plunger projection for positive engagement
• 11 N initial end force to 22 N final end force for light-duty indexing and positioning
• All-steel construction for durability in industrial environments
• Compact body length of 51mm with a 25mm ring diameter for installations with limited clearance

Compatibility

Designed as a standard metric pull ring plunger for use in tapped M12x1.75 holes in machine frames, fixture plates, jigs, and mechanical assemblies requiring manual plunger retraction and locking.

Installation Notes

Installation is performed by threading the PRM12 body into a tapped M12x1.75 hole using the hex head and a standard wrench. De-energize or lock out any machinery before installing or servicing plungers in active equipment. Do not exceed the rated end force by over-tightening or substituting a stronger spring without verifying the assembly design. Confirm plunger alignment with the mating detent hole before applying load to avoid side-loading the plunger shaft.