a clamping device supports or structurally replaces a weld joint between connected pipes . the clamping device includes an upper clamp body and a lower clamp body securable on opposite sides of the connected pipes in facing relation , and at least one clamp bolt connecting the upper and lower clamp bodies and extendable through the connected pipes . one of the upper and lower clamp bodies has at least one shaped depression , which receives a complementary shaped clamp bolt nut engageable with the clamp bolt . the shaped depression prevents rotation of the clamp bolt nut .