Knowledge Base & Engineering Resources

FAQ - Grooved Pins

Frequently Asked Questions About Grooved Pins

Grooved Pins

Q: Where would you use a Grooved Pin?

A: In thousands of places. Here are a few examples:

  • Hinges for rotation
  • Valves for a T-turn
  • Sprinklers as a fulcrum pin
  • Latches for rotation
  • Heat Sinks for locating pins
  • Firearms for holding together the trigger and hammer
  • Conveyor Chain for linking tracks together
  • Hand Tools as swivel pins in universal joints
  • Pumps for spring anchors and locating pins
  • Shaft for locating pin for gears or other attachments
  • Locks for tamper proof assembly

Q: Why would I use a Grooved Pin?

A: There are many reasons:

  • They require only a straight hole, without the need for close tolerances.  The expanded diameter allows for relaxed tolerances in the application hole
  • There are no reaming, milling, or tapping operations involved, keeping production costs low
  • They withstand sever shock and vibration
  • They are solid
  • They are made in different groove types to suit different applications
  • They can provide a smooth bearing surface for rotation
  • They are easy to install.

Q: How does the Grooved Pin work?

A: The expanded diameter gets pressed back to its original size (nominal diameter) when the pin is inserted into the hole.  The pin then tries to return to the expanded diameter but is constrained by the hole's wall.  This constraining action causes a locking fit, which resists sever shock and vibration.

Q: What kind of materials are our standard pins made of?  Surface treatment?




1215 Low Carbon Steel

Cadmium, Zinc, Nickel, Oil, Black Oxide, None.

303 Stainless Steel Passivation, None.
6150 Alloy Steel Cadmium, Zinc, Nickel, Oil, Black Oxide, None

Q: What is the shear strength for Grooved Pins compared to Spring Pins?

A: The Groov-Pin shear strength is up to twice the shear strength of a spring pin of the same diameter.  The shear resistance of alloy steel Groov-Pins can be 40% higher than that of a heavy-duty spring pin.

 Q: What size hole should a Grooved Pin be installed in?

A: The suggested hole size can be found on page 7 in the Grooved Pin Catalog.

 Q: What is the tolerance for overall length and straightness of Grooved Pins?

A: The tolerance for overall length is +/-.010 inch and for straightness +/-010 per inch.

 Q: With what kind of equipment can I install a Grooved Pin?  How much force is required?

A: The Groov-Pin can be pressed in by hammer, air cylinder, or hydraulic press.  For the required insertion force see chart found on page 12 in the Grooved Pin Catalog.

 Q: What is the difference between Tapered Groove and Parallel Groove?

 A: A parallel groove has more engagement between the pin to the hole walls.  A parallel groove has higher pullout strength but requires a higher insertion force.

 Q: How are Grooved Pin dimensions and characteristics measured?


Overall Length Caliper
Pin Diameter Micrometer
Expansion Diameter Ring Gage
Groove Length Caliper