We frequently get questions about finding the proper size of tri-clamp. The following graphic explains how sizing is determined.
Determining the Size of Tri-Clamp Needed
The size of Tri-Clamp needed is determined by the inside diameter of the pipe, not the size of the ferrule.
The ferrule is the end collar on the pipe that forms a connection with another TC fitting (see diagram right).
Ferrules tend to be about 1/2 inch larger than the Tri-Clamp size. Tri clamp sizing is based on the outside diameter of the pipe. The inside diameter is typically about 1/8” smaller than the pipe’s outside diameter.