- Huyett Marketing Department
- 07/22/2020
- Updated 07/11/2024
When it comes to hitch pin clips, it is a somewhat misunderstood category of industrial pin fasteners. Some use the phrase to colloquially refer to bridge pins (or R-clips), cotter pins, or industrial hairpins; others use it to refer to a group of clips used with hitch pin connections, although the grouping varies. Here, we use the term to define a group of clips that attach to the ends of hitch pins, clevis pins, and other similar components with holes or grooves at the end. We will review the types of hitch pin clips, appropriate alternatives, and other important factors about these pin fastener components.
What is a Hitch Pin Clip?
Hitch pin clips are fasteners used to prevent hitch pins from becoming dislodged from their intended application. Whether securing trailer hitches or agricultural implements, these components are an important safety measure that reduces the risk of equipment breaking free and causing catastrophic damage, especially in applications with mobile, removable, or temporary components.
Download a copy of your
Hitch Pin Reference Guide here.
Types of Hitch Pin Clips
Huyett’s category of hitch pin clips includes bridge pins, grip pins hair pins, lock pins, and safety pins. Remember, you will sometimes see “hitch pin clips” used as an informal name for several of these individual clips. The fasteners’ practical uses are very similar, regardless of the naming conventions.
What Are Bridge Pin Clips?
Bridge pin clips (or R-clips; also informally called “hitch pin clips” elsewhere because they are most representative of the category) are the most common mating clip. Defined by their “R” shape and wire-formed body, they typically connect to the holes or grooves in hitch and clevis pins.
Installation is simple; they are pushed and pulled in and out of their mating hole (aided by the loop at the end of the “R”) with hands or a common tool to provide a secure temporary attachment. Installation is even easier since the end is bent upwards, removing the need to manually separate the open ends. These components are essential to have on hand for in-field work.
Bridge Pin Clip Uses
Bridge pins are a great retaining solution for drilled-hole applications, including nearly any variety of hitch pins as well as latches on hitch couplers. You can find them in three-point hitch systems or as an element of temporary connections. They can also be secured using cable tethers to prevent loss.
Double-Loop Pins
Double-loop pins are the heavy-duty version of a bridge pin that uses a double loop to distribute stresses evenly. They last longer and possess a wider application range.
What Are Grip Pin Clips?
Grip pin clips are very similar to bridge pins, except their unique design features a leg bent down perpendicularly to its long leg. It is that downwards bend that locks it into place and reduces the chances of the fastener backing out of its hole. As this pin is inserted into the mating pin, the leg snaps over the mating pin's tail, providing additional security. They are ideal for light to medium duty applications.
Grip Pin Clip Uses
Grip pins are designed for in-hole applications like those found in hitch and clevis pins and certain couplers, where a locking style pin is desired. These are intended for light/medium-duty applications, are reusable (if they are maintained and the bent leg does not lose its locking ability) and are an alternative to bridge pin clips if the additional locking mechanism is necessary.
What Are Industrial Hair Pin Clips?
Industrial
hair pin clips are designed specifically for grooved applications. As the most unique looking hitch pin clip, these components are not closed at any point – this makes them unsuitable for applications with holes. Instead, it would be pushed around a groove in a mating pin and the middle hump would settle into the groove. The loop at the top would still be used like the other loops, serving as an easy handle that would be pulled to remove the clip.
Hair Pin Clip Uses
Since hair pin clips do not close at the end, they are used with components like grooved clevis or grooved headless clevis pins. They should be used in light/medium-duty settings and those that require more specialized retention.
What Are Lock Pin Clips?
Lock pin clips are a variation of bridge pin clips that does not feature a second hump (or loop). Instead, they have an extended leg that aids installation and provides additional length for the component to pass through more than one hole. This is the only pin in this category manufactured to a specification (AA55487).
Lock Pin Clip Uses
Lock pin clips are ideal for drilled, untapped hole applications in military and aerospace environments. Their extended and beveled leg provides improved hole orientation as well as increased reach. The large ring-like loop at the end allows for the addition of a tether to minimize hardware loss.
What Are Industrial Safety Pin Clips?
Industrial
safety pin clips are self-securing industrial pins with a coiled end that provides tension once the straight leg is locked into the hook. They are quick and reusable options that are ideal in applications requiring temporary security.
Heavy-duty safety pin options provide additional tension for the self-lock.
Industrial Safety Pin Clip Uses
Safety pin clips are ideal for retaining clevis pins or as a component in anchor shackle systems. They are also commonly used on industrial and farm equipment, where temporary but durable connections are vital.
How to Use Hitch Pin Clips with Hitch Pins
While each clip will function slightly differently, their shared functionality is to connect to the ends of hitch or clevis pins, which have holes or grooves at the end. A typical use case for these fasteners would be a three-point hitch system:
- Three-Point Hitch System: The configuration found at the rear of a tractor, designed to raise, lower, or transmit rotational power to various attachments like buckets or tillers.
The term "three points" refers to the three connecting arms on the tractor that attach to these implements. In this system, a hitch pin is used to align the holes in the implement and the tractor arm.
The hitch pin clip is a key component in this system; it either threads through the hole or clips around the groove at the end of the pin to keep it from sliding out of the aligned holes. Since these hitch systems are mobile, it is all the more vital that the clip keeps the pin from detaching during use.
Hitch Pin Clip Alternatives
There are several pin fasteners that are sometimes included in hitch pin clip groupings because they can serve the same purpose; in other instances, they are left out because the design is unique enough to set them apart. Here, we list cotter pins, lynch pins, and snap pins as hitch pin clip alternatives for these reasons – they work well in hitch pin applications, but they are widely used in other settings because of their versatile design.
What Are Cotter Pins?
Cotter pins, often called split pins, are steel-formed fasteners designed retain mating components on shafts, whether it be on other fasteners, machinery, or automotive applications. These fasteners are available in many different styles, but the base functionality for most of them is the same: the straight legs are inserted into a hole on the shaft and then bent back around the shaft to keep it in place.
Design variations include different leg shapes and head styles; there are a few types (like bow-tie cotter pins, circle cotter pins, and ring cotter pins) with more unique shapes that offer additional functionalities. For instance, bow-tie cotter pins can be installed from either side, while ring cotter pins provide additional security with a metal loop.
What Are Lynch Pins?
Lynch pins are fasteners with a pin attached to a metal loop; the pin pivots up from the loop to open and insert into a mating component (like a hitch pin or trailer coupler). Once the pin is in place, the loop snaps back down to its closed position to lock itself in place. They are widely used in applications that require quick connection and disconnection without tools.
What Are Snap Pins?
Snap pins, similar to
coil tension pins and
tab lock pins, are fasteners with a pin head attached to a pivoting spring wire. The wire (which can be square or circular) pivots away from the pin during installation so the pin can be inserted into a mating hole; after insertion, the wire snaps back over the end of the pin. Serving similar functions as other hitch pin clip alternatives, these fasteners offer a kind of handle that is helpful when accessibility is a factor.
HITCH PIN CLIP REFERENCE GUIDE
| |||||
|---|---|---|---|---|---|
HITCH PIN CLIP TYPES
| COMMON NAMES
| COMMON USES
| MATERIALS/FINISHES
| WIRE DIAMETER
| COMMENTS
|
 | Hitch Pin Clip; Hair Pin Cotter; Cotter Key
| Retain
clevis pins and
hitch pins in three-point pin and similar temporary connections
| 300 series stainless steel; spring wire with plain or zinc finish
| Easier to remove and reuse than a cotter pin, and more heavy duty; available in a
double-loop style (a heavier-duty bridge pin version)
| |
 | Twist Clip; Self-Locking Pin
| Bent leg snaps over mating pin to lock in place in light-to medium-duty temporary connections
| Spring wire with zinc clear finish
| Bent leg is an easy self-locking device
| |
 | None known
| Retains clevis pins and hitch pins in temporary connections; specified for aerospace usage
| 316 stainless steel
| Manufactured from marine grade 316 stainless steel and is well suited for extreme environments
| |
 | Hair Pin Clip; Hitch Pin Clip; Retaining Pin
| Retains
grooved clevis pins and similar components with grooves; designed for medium-duty use
| Stainless steel; spring wire with zinc finish
| Inch: Between 0.020in 0.188in
| |
 | None known
| Retains clevis pins in anchor shackle and similar systems; used in quick connect/disconnect assemblies
| 300 series stainless steel; hard-drawn spring wire with zinc finish
| Inch: Between 0.047in - 0.243in
| Heavy-duty options available; can be attached to
steel tether lanyards to prevent loss
|
HITCH PIN CLIP TYPES | COMMON NAMES | COMMON USES | MATERIALS/FINISHES | WIRE DIAMETER | COMMENTS |
 | Split Pin; Cotter Split Pin; Cotter Key
| Used in clevis and hitch pins or to secure axles on machinery or vehicles
| Varies based on specific type
| Varies based on specific type
| |
 | Quick Pin; Linchpin
| Used with
three-point pins on tractor implements/trailer couplers; used in temporary equipment connections
| Carbon steel with zinc or black phosphate finish
| Reusable; available in light- and heavy-duty options
| |
 | Snapper Pin; Wirelock Pin
| Used with other three-point pins, PTO assemblies, and quick connect/disconnect settings
| 300 series stainless steel; low-carbon steel with black oxide or zinc finish
| Similar to
tab lock pins and
coil tension pins | |
