Three-Point Pin Features and Types

Huyett Marketing Department
09/02/2020

Innovations in three‑point pin designs have accelerated in recent years, as these devices are now available in more styles and materials than ever before. Most of the designs have been made to improve the compatibility and flexibility of three‑point hitches found on the back of agricultural equipment. Three‑point hitches provide linkage between the power take off (PTO), hydraulics, and hauling capabilities of tractors to compatible implements which can be used for everything from plowing, sowing, and harvesting to mowing, snow removal, and chemical spraying.

Design Considerations

Combinations

Limited only by imagination

Tethers

Can be attached to most three‑point pins

Handle Style

Accommodates ergonomics and style choices

Swivel Lock

The swivel lock will "open" to insert the pin and gravity will allow it to fall perpendicular to the pin securing it without the risk of losing a mating part

Wire Lock

The pivoting wire snaps securely around the pin to prevent the pin from falling out

Reusability

Hitch pins accompanied by mating parts securely connect the two parts together while allowing for quick disassembly

Three-Point Pin Types

Single-Wire Snap

A less expensive version of the double‑wire snap pin. Pin is self‑locking requiring no mating pin.

Double-Wire Snap

Double‑wire snap pins are designed for heavier duty applications. Snap pins should not be used where lateral movement is present.

Single-Wire Tab Lock

Single‑wire snap pins provide a small cost savings vs. double‑wire snap pins. Protrusion of tab should be considered in application.

Double-Wire Tab Lock

Two wires are coiled over the end of the pin into a "tab" shape. This tab provides a lever for quick removal and reinstallation.

Coil Tension

The coiled design provides a spring resistance that helps maintain locking action in presence of lateral movement. A heavy duty version is also available when an application requires more locking strength.

Hitch

Big grip handle is ideal for trailers and wagons. Handle swivels for comfortable ergonomic use.

Color Handle Hitch

Handle is PVC coated in orange or red for an ergonomic grip and easy identification. Pin is heat treated for additional strength.

Swivel Lock

Swivel lock eliminates the need for a secondary part for fastening. These pins should not be used in high‑vibration environments.

Lynch

Single‑piece design uses a spring‑tempered ring that snaps securely in place for rigid control.

Quick Reference Guide

Snap pins are a self‑locking, one‑piece pin with either a rounded or square handle in a single or double wire strand. Tab style eases installation and removal. Hitch pins are used to attach trailers and various turf and agricultural implements, and are manufactured from heat treated steel.

Snap & Tab Lock

Common Names: Snap Pin, Snapper Pin, Wire Lock Pin, Click Pin, Lynch Pin, Lock Pin, Retainer Pin

Applicable Standards: None known.

Fabrication: Cold‑forging of the pin; wire forming of the loop; hand assembly.

How to Identify: Nominal diameter x effective length; single‑wire vs. double‑wire; square loop vs. rounded loop.

Common Uses: Three-point attachments on tractors and turf equipment. Moorings for sails, canvas, tarps, and grommeted covers. Best for frequent removal applications.

Comments: Handles are available in single‑wire or double‑wire versions with rounded or square shapes. Tab lock provides easy‑grip handle for removal.

Coil Tension

Common Names: Tractor Pin, Snap Pin, Snapper Pin, Three‑Point Pin, Lock Pin

Applicable Standards: None known.

Fabrication: Cold‑forging of the pin; welding of collar for heavy duty version; wire forming of the loop; hand assembly.

How to Identify: Nominal diameter x effective length; standard duty vs. heavy duty.

Common Uses: Heavy duty agriculture and industrial attachments, where the extra protrusion of the wire spring loop does not interfere.

Comments: Wire is coiled to allow lateral play for heavier duty stretching of wire lock mechanism. Welded collar acts as a stop for heavy duty applications. Pin shaft is grooved to mate with wire assembly for added strength.

Hitch

Common Names: Trailer Pin, Red Handle Pin

Applicable Standards: None known.

Fabrication: Cold‑forging; welding of collar; cross drilling; wire forming of handles; hand assembly; heat treatment; dipping of handle where applied.

How to Identify: Nominal diameter x effective length; handle shape.

Common Uses: Trailers, especially light duty commercial and agricultural. Use where frequent disconnect is needed.

Comments: Use with bridge pin. Numerous design styles and types. Loose fitting allows designs to be interchangeable.

Lynch

Common Names: Snap Pin, Self‑Locking Pin, Click Pin, Lock Pin

Applicable Standards: None known. DIN 11023 for metric.

Fabrication: Hot‑forging of the pin; formation of the wire; hand assembly.

How to Identify: Nominal diameter x effective length.

Common Uses: Lighter duty agriculture. More constrained length limits use to retaining rather than as a pivot or lock mechanism. Usually a round pin but square pins are available.

Comments: Lynch pins can be supplied with chain and cotter for fixed attachment eliminating accidental loss.

Using Three-Point Pins

When used in a three‑point hitch application, three‑point pins and their mating parts provide easy connects/disconnects between an implement and a tractor. Using tethers to semi‑permanently attach the pins to the hitch eliminates separate storage or potential loss.