| 摘要 |
A power tong assembly for forming and breaking joints between pipe sections is described. The assembly has suspension means that include struts 26 extending downwardly from an upper powered tong (Figure 1, 10) to a lower powered backup tong (Figure 1, 12). These struts 26 either incorporate, or are connected to one of the tongs by joints 26a, that can be selectively rigid or flexible; so that lower portions of the struts have a degree of lateral and angular freedom of motion when the power tong assembly is suspended. However, the struts 26 are effectively rigid when supporting at least part of the vertical load of the powered tong, when the tong assembly is placed on a support surface (Figure 5). |
