Many little parts make up overhead lifting rigging setups. Apart from the larger pieces like ropes, slings, and chains, overhead lifting hardware includes many smaller parts that are necessary for holding these setups together. One such piece is the eye bolt.
The purpose of the eye bolt is to create a secure point of connection. They can be used as an anchor or as part of a push, pull, or hoisting apparatus. You’ll see eye bolts used in more than just overhead lifting. They are also used in industrial applications, construction, and even household projects.
Of course, the types of eye bolts used as overhead lifting hardware are far more heavy-duty than the types you’ll find lying around in someone’s garage. These types are only offered by an industrial hardware supplier, as they must meet specific weight load limits.
Here’s what you need to know about the different types of eye bolt hardware:
1. What is Industrial Eye Bolt?: The Basics of the Eye Bolt
The eye bolt is a type of screw that is held securely in place with a corresponding nut. Amazingly, the first type of bolt was made back in 400 BC – and the general design has changed very little over time. An eye bolt is characterized primarily by its rounded opening on one end – known as its “eye.”
The “eye” is offered in a variety of diameters and may be welded, forged, or bent into shape. Beneath the eye is the “shoulder” or “skirt”, which is a slightly widened area between the screw and the eye. This slightly thicker design helps to prevent the entire bolt from bending or warping.
The final part of the eye bolt is the shank, which is the threaded portion attached to the eye. This is where a bolt may be attached to hold the entire piece in place.
Every piece of industrial eye bolt hardware will have specific markings, typically on the eye. This will show the name or trademark of the manufacturer, the size or rated load, and the grade of the steel.
Eye bolts can be used in overhead lifting applications to secure wires, chains, straps, or cables together. It is very important to double-check the size or load rating on the eye bolt as a safety precaution when used for rigging purposes.
The angle of the rated load applied to the eye bolt is very important. If the load is applied at an angle higher than 45°, it will reduce the working load limit (WLL) of the hardware. Therefore, you must be very particular when purchasing eye bolt hardware and choose the type with the appropriate WLL for your intended use.
Now, let’s dive into the main types of industrial eye bolt hardware used for these applications:
Types of Industrial Eye Bolts
1. Shoulder Nut Eye Bolts
A shouldered eye bolt basically means that it has a defined shoulder between the eye and the shank – some eye bolts don’t have this. This eye bolt hardware type also comes with a traditional bolt piece that threads around the shank.
This kind of bolt is used for vertical in-line or angular lifts, as the shoulder adds extra support. Non-shouldered bolts are more prone to bending and are not approved for angular lifts.
Shoulder eye bolts often come in a galvanized finish to protect the forged carbon steel from corrosion. This material can be left out in the elements or exposed to water without oxidizing. They are available in a variety of sizes based on bolt diameter and shank length and have a working load limit of up to 24,000 lbs.
2. Shoulder Type Machinery Eye Bolts
A shoulder-type machinery eye bolt is differentiated by its intended purpose. Rather than being held in place with a threaded nut, it is made to be inserted into structures through equally sized holes. This allows the eye to be used as a lifting point for angular holds of up to 45°.
Most shoulder-type machinery eye bolts are made with carbon steel that is quenched and tempered. This means the metal is heated and formed into shape and then rapidly cooled in water to set it.
You can purchase a shoulder-type machinery eye bolt from an industrial hardware supplier in a variety of sizes depending on the weight load. The largest of these types of eye bolts have a maximum working load limit of 24,000 lbs.
3. Regular Nut Eye Bolts
The final type of eye bolt commonly offered by industrial hardware suppliers is the regular nut eye bolt. This is a traditional design that includes a nut for securement. However, the neck between the eye and the shank is quite long.
Regular eye bolts are drop forged, which helps to add strength as the shape is made from one continuous piece of metal. However, the long neck does make the eye bolt more prone to bending or warping under heavy loads, so it is not approved for angular loading. It should only be applied for vertical or in-line rigging lifts.
4. Other Types of Eye Bolts
You may see other types of eyebolts offered. However, these are not necessarily designed as overhead lifting hardware.
For instance, some types of eye bolts come with a bent eye, which means the opening is bent into shape rather than forged. This is far less secure and may bend under a heavy load, so it is not recommended for rigging.
You may also purchase screw eye bolts, which have a sharpened point at the end of the threaded shaft. This allows the bolt to be screwed into place so it can be inserted into structures made of wood or concrete. However, these are designed for lighter loads and are not approved for overhead lifting purposes.
Back to You
As with any type of overhead lifting hardware, you need to be sure you’ve got the right shape, size, and material for the job at hand. If you don’t, the results could be disastrous.
If you’re on the hunt for top-quality overhead lifting hardware including a variety of eye bolts, come to Elite Sales. We proudly carry a wide selection of eye bolts in different designs and diameters so you can find the exact type for your intended application. Plus, our knowledgeable staff is on-hand to answer any questions and point you in the right direction.