Tri Clamp Information and Sizing Guide

A Cutaway Diagram of a Tri Clamp Connection

Tri Clamp Cutaway Diagram

Tri Clamp sanitary fittings (also known as Tri Clover fittings) are one of the most common types of connections in the food and beverage industries. A Tri Clamp sanitary connection typically consists of two Tri Clamp ferrules or flanges, a Tri Clamp Gasket, and a Tri Clamp to mechanically hold the connection together.
These connections can be permanent or semi-permanent, using bolted high pressure Tri Clamps, or they can be connected with fold over, two segment style Tri Clamps for ease of disassembly and ease of cleaning.

Determining Tri Clamp Size

Tri Clamp sizes are determined by the outer diameter of the pipe or tubing, not the outer diameter of the flange or Tri Clamp itself. The flange of a Tri Clamp fitting typically has about a ½” inch greater diameter than the outside diameter of the pipe. This can become especially confusing when the Tri Clamp fitting has no pipe attached to it, as is the case with adapters, For instance, a 1.5" Tri Clamp to 1/2" hose barb adapter is not 1.5" inches in any dimension, but the Tri Clamp end will fit any other 1.5" Tri Clamp fitting.

Another thing to consider when dealing with smaller pipe diameters is that some smaller diameter piping uses flanges for a larger diameter pipe, for example the 1" Sanitary Spool uses the same flanges as the 1.5" Sanitary Spool.

If you have any doubts about what size Tri Clamp fittings your project needs, simply measure the outside diameter of the flange (dimension "B" below) and consult the chart below, or feel free to contact us .


 
Pipe Outer Diameter
A
Flange Outer Diameter
B
Pipe Inner Diameter
C
Tri Clamp Dimension Diagram
1"
1.98"
.87"
1.5"
1.98"
1.37"
2"
2.52"
1.87"
2.5"
3.05"
2.37"
3"
3.58"
2.87"
4"
4.68"
3.83"
6"
6.57"
5.78"
8"
8.57"
7.78"
10"
10.57"
9.69"
12"
12.57"
11.81"
Manufacturer dimensions may vary slightly

Gasket Selection

Selecting the proper gasket for your application is an important step in ensuring leak free operations, while maintaining safe and sanitary conditions.

Diagram Showing Correct
and Incorrect Gasket Installation

Tri Clamp Gasket correct and incorrect installation

Sizing

Normally you will select a gasket size based on the type of Tri Clamp you are using, for example a 3" Tri Clamp connection will use a 3" Tri Clamp gasket. However there are exceptions for specific use cases, for example, when connecting a 1" sanitary spool (which uses 1.5" fittings) to a 1.5" sanitary spool you should use a 1.5" gasket. Using a 1" gasket in this case can create an unsanitary gap inside the connection.

Material Selection

Tri Clamp gaskets come in a variety of materials such as, Silicone, Viton, Buna, and PTFE (commonly known as Teflon).