What are Eye Nuts?
Eye nuts are female-threaded rings that screw onto a stud or bolt to create a rated attachment point for a shackle, hook, or sling. Ours are USA made by Ken Forging and drop forged for dependable strength.
Styles of Eye Nuts
- Style A: Compact general-purpose eye nut for straight, in-line loading.
- Style B: Heavier head and bell than Style A for higher capacity in the same thread sizes.
- Style D: Heavy-duty pattern with larger section for rugged service.
- Style E: Large eye opening for extra shackle or hook clearance (select sizes).
Materials and Finishes
- Forged carbon or alloy steel: Heat treated for strength in shop and field use.
- Stainless steel: 18-8 and 316 for marine or washdown environments.
- Corrosion protection: Zinc plated or hot-dip galvanized options.
How to choose the right Eye Nut
- Thread match: Pick the exact thread diameter and pitch for your stud or bolt.
- Working Load Limit: Choose a WLL that meets or exceeds your service load after any angle derating.
- Eye clearance: Confirm the opening fits the shackle pin or hook without binding.
Installation tips for Eye Nuts
- Seat the eye nut squarely on a flat surface or hardened washer.
- Engage full threads. A common target is at least one bolt diameter in steel.
- Align the eye with the direction of pull. Use pairs for multi-leg slings so pulls are in plane.
- For frequent off-axis pulls, choose a swivel hoist ring instead of a fixed eye.
Common applications
- Permanently threaded lifting points on machinery, molds, and fixtures
- Tie-downs on skids and transport frames
- Rigging picks where a compact female-threaded ring is preferred
FAQs about Eye Nuts
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Can eye nuts be used for lifting?
Yes, when used in line with their rated Working Load Limit and installed correctly. Avoid side loading unless the manufacturer allows it with derating.
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Eye nut vs eye bolt — what is the difference?
An eye nut threads onto an existing stud or bolt. An eye bolt is a one-piece male-threaded lifting point that screws into a tapped hole or passes through and nuts on the backside.
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How much thread engagement is required?
Use full engagement. A simple rule is at least one bolt diameter of threads in steel, more for softer materials.
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What size shackle fits my eye nut?
Choose a shackle whose pin sits freely in the eye without rubbing. Match or exceed the eye nut’s WLL.
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Stainless vs carbon steel — which should I choose?
Choose stainless for corrosion resistance in marine or washdown areas. Carbon or alloy steel is common for general indoor or outdoor use with protective coatings.