Pipe Fitting Squares

A pipe fitting square checks that a fitting or flange sits true to the pipe before you tack it. Most fitters improvise with a framing square, a level, or a tape measure, but none of those tools is shaped to sit against a curved surface. That makes small errors easy to miss until the weld is done. Our squares are shaped to register against both the pipe and the fitting face at the same time, so you can see whether a 45° or 90° is square to the run. The flange side of the Tri-Square does the same for flange faces. Catching a fitting that is a degree or two off during fit-up takes seconds. Catching it after the weld usually means cutting it out.

Both squares are laser cut from 3/16″ aluminum, which keeps their edges accurate and their weight low enough to carry all day. Aluminum also won’t rust in your truck box the way a steel square can. The Tri-Square design is protected under U.S. Patent No. D987,449, and it is made only by H&K Fabrication. If you fit up a lot of flanges, our 2-hole welding clamp pairs well with the Tri-Square for aligning bolt holes before tacking.