One of the most common hardware fasteners are eyebolts. They can be used in a variety of applications including providing a way to anchor equipment and machinery to surfaces, piping and any other kind of construction. If you were looking for a guide on what eyebolts are used for and just some of the industries that use them every day, then look no further.

 So what are eyebolts?

An eyebolt is a ring-shaped mechanical fastener with a threaded shaft and a ring-shaped head. Eyebolts are used to secure a rope, cable, or shackle through a bolt that is attached to a structure.

Eyebolts come in multiple different designs depending on their intended use. Here are some key terms that are worth understanding when choosing which eyebolt is right for you:

  • Eye: The eye is a loop formed at the top of a bar that can be either bent, welded, or forged to support the rope, cable or pulley.
  • Shoulder: This is the place where the eye and shank meet to prevent bending.
  • Shank – The shaft or bar that attaches to the eye.

 What are eyebolts used for?

An eyebolt is commonly put directly into a hole in a structure when lifting machinery. Multiple eyebolts can be used to reduce the tension of the load.

Some specific designs of eyebolts are as follows:

  • Anchor eyebolts: Anchor eyebolts have an anchor bolt that enables them to be secured to a masonry structure. The anchor eyebolt is ideal for nautical, industrial, and architectural applications.
  • Eye nut: An eye nut consists of the top ring part of the eyebolt fastened to a flat surface base rather than a bar. They are usually permanently mounted to industrial machinery or equipment and are mostly employed for lifting, rigging, lashing, or as an anchor point for other rigging equipment.
  • Pigtail eyebolts: These consist of a length of bar with a bent head, wherre the head is not bent all the way over, so it doesn’t fully close on itself, like a hook. This way, the rope or cable can be fastened without needing to be threaded through the end.
  • Roller eyebolt: The roller eyebolt consists of four rollers guiding the rope through it.
  • Screw eyes: Screw eyes utilise a wood screw instead of a machine screw and are commonly used to attach to plastic or wood. They are often used to hang picture frames.
  • Ringbolt: This eyebolt has a captive ring passing through the eye of the head, forming two chain links.

What are the benefits of using forged eyebolts?

  • Low-strength eyebolts: These consist of a length of bar with a bent head to form a ring shape. While these can carry some loads, they should not be used for heavy-duty lifting or off-axis loads. Even if the small opening between the bent head and bar is welded together, it can still be a cause for breakage.
  • High-strength eyebolts: Forged heads with a considerable shoulder are common on high-strength eyebolts. They can support substantial off-axis stresses thanks to the shoulder. In lifting applications where lifting slings with many legs are used to attach to several lifting eyes, the capacity to withstand off-axis weights is critical.

Eyebolts can either be forged or bent, and both applications greatly affect the maximum pressure they can support without breaking.

Forged Eyebolts

Forged eyebolts are battered into shape, altering the metal lattice’s ionic bonds, creating a more dense and durable material.

Bent Eyebolts

Bent eyebolts differ from regular forged eyebolts in that the head doesn’t form a closed-loop attached to a bar but rather consist of a bent loop stemming from the bar. As the process of bending this piece can sometimes alter the integrity of the metal, it is recommended that bent eyebolts be used for less high-performance uses and tensile loads, and instead op for reinforced forged eyebolts for things like angular-loading application and heavier support,

 So which eyebolt is right for me?

Used as a lifting point, eye bolts are one of the most common types of rigging hardware and can be used in rigging, anchoring, pulling, pushing, or hoisting applications.

There are several things you can consider to determine the eyebolt to use:

  • The application of the lift.
  • The material the eye bolt is being installed into
  • The angle of the vertical load
  • The weight and pressure of the tensile load

Although eye bolts are commonly used in industrial applications, it’s easy for damage or improper use if not properly installed and utilised. It can be confusing to understand what type of eye bolt to use for your application, and by understanding the type, design, and specifications of each eyebolt, you can ensure you are choosing the product that’s right for you.