General Collar Repair

General Collar Repair Specifications

This specification applies to the following types of trench shields:
3M, 4L, 4M, 6M, 8M, T, E, N, K, and LD

  • All welding shall be performed according to the Structural Welding Code for Steel - AWS D1.1-90
  • A certified welder shall perform all welding.
  • 70,000 psi welding rod or wire shall be used to complete the welds.
  • 3/16" steel sheet with a 55,000 psi minimum yield strength shall be used to replace the skin plate cut away from the collars.
  • The Replacement Collar shall be manufactured by GME.
  1. Trim the skin plate around collar on both sides of the shield.
  2. Cut old collar out, being careful not to cut into the vertical tubes. Clean the area to be welded thoroughly with a wire brush or grinding wheel.
  3. Weld the replacement collar to the tubes in all accessible locations use a continuous 3/16" fillet weld. The trench shield should be rolled over and the other side of the collar should be welded in the same manner to the vertical tubes.
  4. Replace the skin plate using the steel sheet specified above. Weld all around the new sheet with a 1/8" fillet weld to prevent water and mud from entering the shield.

In accordance with OSHA regulations, a Registered Professional Engineer must observe and provide written conformation that the above specification has been followed as authorized by the factory or the Tabulated Data will no longer be valid.

collar repair