| 摘要 |
A torque transfer apparatus and method wherein a device such as a pipe tong is provided with hard metallic inserts (steel) on the tong jaws with thin facing material (bonding key material) which is interposed between the surface of the pipe and the insert. This soft bonding key material, aluminum or bronze sheeting, or coatings of soft alloy, under pressure by the clamping force of the tong jaws flows into the imperfections in the pipe and the imperfections in the insert thereby creating a bond. The bond fails when the applied torque overcomes the shear strength of the key material, shearing off small protrusions from the surface of the key material. This leaves the pipe surface undamaged. The surface of the inserts are provided with grooves and drainage holes and to insure greater contact with the pipe whose diameter may vary, the inserts are made from spring steel with a smaller diameter than that of the pipe so that when the clamping force is applied, the insert and the bonding key material straighten out and wrap around the pipe. |
