There are many considerations for selecting the ideal sanitary clamp, also called a Tri-Clamp. This online guide walks you through the steps.
Clamps may fasten with a single bolt, having double pin hinges on the other side, or they may fasten with bolts on each sides (no hinge). Clamps required for certain high pressure ASME applications have three bolts, including a bolt on the hinge side. Other manufactures may offer clamps with a single pin hinge. We believe that two-pin types provide a more sturdy and even clamping force. In situations where ferrules from different manufacturers need to be mated, L.J. Star’s Advanced Coupling clamp has been designed to provide an efficient, leak-proof connection. The unique profile design pushes the ferrules into proper alignment with high clamping efficiency, reducing the chance of a failed connection.
A beveled surface on the outside diameter of the ferrule mates with the inside diameter of the clamp. Tightening the clamp pulls the two ferrules together and creates a seal. Therefore, the size of the clamp is based on the size of the ferrules that it is mating. Sizes typically range from ½” to 12” for tubing and 4” to 12” for pipe. Sizes and dimensions are standardized by ASME BPE.
Note that the outside diameter of the flange is the same for 1/2” and 3/4” fittings, as well as for 1” and 1-1/2” fittings. Therefore, measure the outside diameter of the tubing, not the flange, when sizing gaskets.
Clamps are typically constructed of 304 or 316 stainless steel. The 316 stainless steel offers superior corrosion resistance.