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Modification and Repair of Double Grip Coil Tong

Modification and Repair of Double Grip Coil Tong

Modification and Repair of Double Grip Coil Tong
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Repair, Modification, and Certification of Double Grip Coil Tong for the Silicon Steel Industry

A double grip vertical coil tong had been experiencing failures during operation which included; pins failure, inner lever failure, finished coil damage, and excessive clevis wear. Our customer sent the lifter to us with hopes we could redesign the device to eliminate the problems.

Hunter Lift observed the tong in use to gain a good understanding of how the lifter was being used. We were able to draw upon our many years of expertise to evaluate and determine what was causing some of the issues. Our engineers performed calculations and Finite Element Analysis to examine and locate high-stress areas within the tong components.


The repairs and modification to the vertical tong lifter included:

  • Increased boss sizes to reduce bending stress in loaded pins
  • Clevis plates were changed from plain carbon steel to high strength alloy steel to reduce wear
  • Stronger springs were added to aid in the operation of the lifter
  • Redesign of the shoes to increase the contact area and reduce marking on finished coil surfaces

The re-engineering of the double grip vertical coil tong has resulted in lower repair cost and less downtime for maintenance.


Double Grip Coil Tong

Our client’s double grip vertical coil tong had continuous failures and was causing damage to the product, so it was sent to Hunter Lift for evaluation and subsequent repair and modifications


  • Pin Breakage
  • Inner Lever Failure
  • Finished Coil Marking
  • Excessive Clevis Wear
  • Tong Sticking During Operation


  • Lower repair costs
  • Less downtime for maintenance
  • Ability to move hotter coils out of annealing without increasing damage

Weight Capacity

  • 16,000 lbs

Industry for Use

  • Silicon Steel

Delivery Time

  • 10 weeks

Standards Met

  • ASME B30.20
  • ASME BTH-1
  • AWS D14.1