Guidelines for the proper use of lifting eyes

Lifting eyes, also commonly known as eye bolts, have widespread use in industrial plants. They are commonly used on dies, cabinets, compressors, heat exchangers, motors, molds, and other equipment to facilitate their movement, either when being installed or moved to a different plant location.


Key Concepts
  • Only forged lifting eyes have certified capacities.

  • Never exceed rated capacity.

  • Lifting eyes must have traceability markings.

Forged vs. bent wire
Safety inspections
Dangerous alterations
Tips for smart lifting eye usage

Lifting eyes, also commonly known as eye bolts, have widespread use in industrial plants. They are commonly used on dies, cabinets, compressors, heat exchangers, motors, molds, and other equipment to facilitate their movement, either when being installed or moved to a different plant location.

In a world increasingly conscious of product litigation, it is critically important to understand the proper selection and use of lifting eyes. It obviously pays the plant engineer to be aware of the risks when an undersized lifting eye is used; the correct size is abused, altered, or improperly loaded; or a bent wire eye is substituted for a forged one (Fig. 1). If recommended guidelines are not followed, the failure of a lifting eye can result in loss of property, personal injury, or even death in extreme cases.

Forged vs. bent wire

Whenever lifting is to be accomplished with a threaded eye bolt or lifting eye, a forged product should be used as compared to a carbon steel or bent wire eye bolt. Bent wire eyes, even if welded, are made from low-carbon steel. They can open up or stretch under load and are not designed or intended for lifting. They have no rated capacity associated with them.

Bent wire eyes are not physically tested, and because of their low carbon steel content, they exhibit very poor mechanical properties. They may be specified for nonlifting or nondynamically loaded applications, but they should never be used where product integrity and worker safety is of concern.

A situation may occur where a standard forged lifting eye that is properly sized for an existing tapped hole does not possess the rated capacity to safely handle the load to be lifted. What are the options? It may be possible to use an alloy forged lifting eye whose rated capacity is from 8% to 25% higher than a comparable standard forged lifting eye.


Using an undersized forged lifting eye or a bent wire substitute can lead to distortion of the eye, shank, or threads and is a leading cause of catastrophic failure. For this reason, manufacturers and ASTM Rated Capacity Tables (see table) state the maximum working load for various sizes of forged lifting eyes or eyebolts to aid in selection. A supplier/manufacturer of lifting eyes can supply these charts.

Never exceed rated capacity . It is a good idea to post a capacity table in work areas where lifting eyes are used and make it an active part of a safety program.

Even though the greatest load bearing capacity is in the plane of the eye and along the centerline of the shank, a properly sized but misused lifting eye can fail. It is important never to lift outside the plane of the eye. Lifting at an angle from the shank's centerline significantly reduces the lifting eye's capacity. Even a 45-deg angle reduces capacity. In any case, never exceed a 45-deg angle.

There are two types of capacities given for lifting eyes: Riggers and Engineering. The Riggers Capacity refers to the actual load a single lifting eye can lift. It varies with the angle between the leg of the lifting rig and the shank of the lifting eye.

Engineering Capacity refers to the allowable tension in the leg of the lifting rig as it is applied to the eye and is specifically useful when the load distribution is nonuniform, when nonsymmetrical slings are required, or when the lifting eyes are not placed on the top surface of the load.

Engineering Capacity must be calculated using trigonometry and vector analysis based on the actual loading configuration. More complete information describing how these working loads are determined may be found in ANSI B.18.15 Standard, Metric Straight Shank Lifting Eyes .

It is mandatory that the tapped receiving hole for the threads on the lifting eye have the proper major pitch and minor thread diameters, hole depth, and configuration (Fig. 2). The eye should not wobble while being screwed in nor should it take excessive force to screw in the lifting eye.

To prevent unscrewing due to twist of a cable and applied load on the hoisting device, the lifting eye should be screwed into the tapped hole with firm hand pressure and the eye aligned with washers, if necessary, so the applied load is in the plane of the eye.

Do not use a "Cheater Bar" to tighten the lifting eye. Installation instructions must be followed to ensure the initial load on the lifting eye hasn't unseated the eye. If this happens, the eye should be unloaded and properly reseated. The hole for the lifting eye must have a counterbore to ensure snug seating of the shoulder of the lifting eye. Washers can be used to ensure snug seating of the eyebolt shoulder as long as there is a 90% minimum thread engagement.

Safety inspections

Can lifting eyes be reused? Yes, but with caution. Before each use lifting eyes should be inspected and replaced if any of the following is detected:

  • Elongated or bent eye section

  • Elongated or bent shank

  • Nicks or gouges

  • Obvious wear

  • Worn, corroded, and/or distorted threads

  • Cracks found by nondestructive testing, or magnetic particle inspection.

    • Lifting eyes that are being replaced should be destroyed by melting, crushing, or cutting clear across the eye. There are no other acceptable means of eliminating defective lifting eyes from possible reuse. The lifting eye should also be removed from service and destroyed when the name and/or trademark of the manufacturer is no longer readily identifiable to guarantee proper reference for continued usage.


      Once the proper size forged lifting eye is identified, a source of supply should be determined. Beyond price and delivery considerations, insist on full compliance for proper traceability. Traceability markings should include the proper shank diameter, forging cavity number, forging code to identify manufacturing equipment used, manufacturer's trademark, and material heat code that refers to the specific heat of steel used (Fig. 3). All of these markings are important and are an assurance of a quality supplier and product.


      For highly corrosive environments, specify stainless steel forged lifting eyes. Since individual environments in this category have their own particular hazards, it is wise to consult an engineer to specify the correct material for an application.

      When lifting outdoors in subfreezing weather, use a forged alloy lifting eye to reduce the chance of brittle failure. Contact a supplier for specific information on forged alloy lifting eyes.

      More Info: For additional information or visual aids, contact Charles W.. Smith, President, Edward W. Daniel Company. Call toll free to 800-338-2658. Article edited by Joseph L. Foszcz, Senior Editor, 630-288-8776, .

      Lifting eye capacities

      Diameter, in. Rated capacity, lbs.
      45° over 45°
      1/4"500125 Not Recommended
      5/16"900225 Not Recommended
      3/8"1300325 Not Recommended
      7/16"1800450 Not Recommended
      1/2"2400600 Not Recommended
      9/16"3200800 Not Recommended
      5/8"40001000 Not Recommended
      3/4"50001250 Not Recommended
      7/8"70001750 Not Recommended
      1"90002250 Not Recommended
      1-1/8"12,0003000 Not Recommended
      1-1/4"15,0003750 Not Recommended
      1-1/2"21,0005250 Not Recommended
      1-3/4"28,0007000 Not Recommended
      2"38,0009500 Not Recommended
      2-1/2"56,00014,000 Not Recommended

      Dangerous alterations

      In general, a lifting eye must never be altered by such means as grinding, machining, or cutting. Dangerous alterations of eyebolts that can contribute to catastrophic failures include:

      Machining an undercut in a shoulder lifting eye if a noncounterbore/countersunk hole is used.

      Cutting undersized threads on a blank lifting eye to make it fit.

      Welding another piece of metal to the eye or heating it in any way.

      Rapidly loading the lifting eye in shock, especially at ambient temperatures below 30 F

      Grinding the eye to make it fit a tight space.

      Tips for smart lifting eye usage

      Have backup inventory to ensure that the proper lifting eye is selected instead of using what's available.

      Schedule regular instructional sessions on the safe use of lifting eyes for maintenance and plant engineering personnel. Distributors and manufacturers are usually happy to put these on.

      Make use of free safety posters and pocket cards are available from leading manufacturers.

      Establish a regular lifting eye safety inspection schedule and procedure that is strictly enforced.

      Replace all lifting eyes at least once per year.

Top Plant
The Top Plant program honors outstanding manufacturing facilities in North America. View the 2017 Top Plant.
Product of the Year
The Product of the Year program recognizes products newly released in the manufacturing industries.
System Integrator of the Year
Each year, a panel of Control Engineering and Plant Engineering editors and industry expert judges select the System Integrator of the Year Award winners in three categories.
May 2018
Electrical standards, robots and Lean manufacturing, and how an aluminum packaging plant is helping community growth.
April 2018
2017 Product of the Year winners, retrofitting a press, IMTS and Hannover Messe preview, natural refrigerants, testing steam traps
March 2018
SCCR, 2018 Maintenance study, and VFDs in a washdown environment.
April 2018
ROVs, rigs, and the real time; wellsite valve manifolds; AI on a chip; analytics use for pipelines
February 2018
Focus on power systems, process safety, electrical and power systems, edge computing in the oil & gas industry
December 2017
Product of the Year winners, Pattern recognition, Engineering analytics, Revitalize older pump installations
Spring 2018
Burners for heat-treating furnaces, CHP, dryers, gas humidification, and more
April 2018
Implementing a DCS, stepper motors, intelligent motion control, remote monitoring of irrigation systems
February 2018
Setting internal automation standards

Annual Salary Survey

Before the calendar turned, 2016 already had the makings of a pivotal year for manufacturing, and for the world.

There were the big events for the year, including the United States as Partner Country at Hannover Messe in April and the 2016 International Manufacturing Technology Show in Chicago in September. There's also the matter of the U.S. presidential elections in November, which promise to shape policy in manufacturing for years to come.

But the year started with global economic turmoil, as a slowdown in Chinese manufacturing triggered a worldwide stock hiccup that sent values plummeting. The continued plunge in world oil prices has resulted in a slowdown in exploration and, by extension, the manufacture of exploration equipment.

Read more: 2015 Salary Survey

The Maintenance and Reliability Coach's blog
Maintenance and reliability tips and best practices from the maintenance and reliability coaches at Allied Reliability Group.
One Voice for Manufacturing
The One Voice for Manufacturing blog reports on federal public policy issues impacting the manufacturing sector. One Voice is a joint effort by the National Tooling and Machining...
The Maintenance and Reliability Professionals Blog
The Society for Maintenance and Reliability Professionals an organization devoted...
Machine Safety
Join this ongoing discussion of machine guarding topics, including solutions assessments, regulatory compliance, gap analysis...
Research Analyst Blog
IMS Research, recently acquired by IHS Inc., is a leading independent supplier of market research and consultancy to the global electronics industry.
Marshall on Maintenance
Maintenance is not optional in manufacturing. It’s a profit center, driving productivity and uptime while reducing overall repair costs.
Lachance on CMMS
The Lachance on CMMS blog is about current maintenance topics. Blogger Paul Lachance is president and chief technology officer for Smartware Group.
Maintenance & Safety
The maintenance journey has been a long, slow trek for most manufacturers and has gone from preventive maintenance to predictive maintenance.
Industrial Analytics
This digital report explains how plant engineers and subject matter experts (SME) need support for time series data and its many challenges.
IIoT: Operations & IT
This digital report will explore several aspects of how IIoT will transform manufacturing in the coming years.
Randy Steele
Maintenance Manager; California Oils Corp.
Matthew J. Woo, PE, RCDD, LEED AP BD+C
Associate, Electrical Engineering; Wood Harbinger
Randy Oliver
Control Systems Engineer; Robert Bosch Corp.
Data Centers: Impacts of Climate and Cooling Technology
This course focuses on climate analysis, appropriateness of cooling system selection, and combining cooling systems.
Safety First: Arc Flash 101
This course will help identify and reveal electrical hazards and identify the solutions to implementing and maintaining a safe work environment.
Critical Power: Hospital Electrical Systems
This course explains how maintaining power and communication systems through emergency power-generation systems is critical.
click me