Vlier PHB56 Threaded Ball Plunger 5/16-18

Product Description

The VLIER PHB56 is a threaded ball plunger designed for controlled end-force applications in mechanical assemblies, tooling fixtures, and positioning systems. The body is machined from steel with a zinc-plated finish and houses a stainless steel ball measuring 0.156 inches in diameter. The 5/16-18 thread allows direct installation into tapped holes without secondary hardware. With an initial end force of 4 pounds and a final end force of 9 pounds, the PHB56 delivers predictable, repeatable detent or indexing force across its 0.04-inch maximum ball reach. Body length is 0.72 inches. This plunger is installed by machinists, toolmakers, and mechanical assembly technicians.

The PHB56 is suited for controlled end-force applications where consistent ball engagement is required. Typical uses include detent positioning in jigs and fixtures, panel alignment, drawer stops, and light-duty indexing mechanisms. The zinc-plated steel body resists corrosion in light-duty industrial environments, while the stainless steel ball provides durability at the contact point. This plunger fits any application requiring a 5/16-18 threaded mounting hole and controlled spring force within the stated range.

Key Features

• 5/16-18 thread for direct installation into standard tapped holes
• Stainless steel ball, 0.156 inches in diameter, for wear resistance at the contact point
• Controlled end force: 4 pounds initial, 9 pounds final
• Maximum ball reach of 0.04 inches for precise detent travel
• Zinc-plated steel body for corrosion resistance in light-duty environments
• Compact 0.72-inch body length suits space-constrained assemblies

Compatibility

Designed for use in any mechanical assembly or fixture requiring a 5/16-18 threaded ball plunger with controlled end force in the 4- to 9-pound range.

Installation Notes

Install using a hex key or wrench appropriate for the body drive style into a clean, properly tapped 5/16-18 hole. Ensure the receiving hole is free of debris before threading in the plunger. De-energize or lock out any machinery before servicing assemblies that contain this component. Do not exceed the rated ball reach, as overextension can reduce service life or affect detent force consistency.