CETC : TriClamp connection elements

Tri Clamp Dimensions & Sizing

The Tri Clamp pipe connection fittings (also known as Tri Clover or sanitary fittings) are widely used in food, beverage, pharmaceutical and biotech applications. The following table explains how Tri Clamp sizing works.

Nominal Tri Clamp sizes are based on the outer diameter (D1) and the inner diameter (D2 / DN) of the tube (for example 1.5″ OD tube), not on the clamp or the connection flange outside diameter.

A complete Tri Clamp connection consists of:

• Two flat flanges (ferrules) / connection discs (welded to the tubes)
• One clamp (that closes around the flanges)
• One gasket (placed between both flanges – providing the seal)
• All parts must be the same Tri Clamp size (for example 2″) so that the flange outer diameter, clamp and gasket match.

How to Measure Tri Clamp Components

Tube (D1, D2):

D1 is the tube outer diameter (nominal size). D2 is the typical tube inner diameter for the given wall thickness (it is also called as DN).

Flat flange (Ferrule) :

Measure the flange outside diameter (clamp flange). This tells you which clamp and gasket series you need (34 mm, 50.5 mm, 64 mm, 91 mm, 106 mm, 119 mm, 167 mm, 155 mm, etc.).

Clamp:

The clamp is selected by the flange OD, not by tube size directly.

Gasket:

Choose the gasket by the same flange OD. For hygienic processes it is good practice to select a gasket whose inner diameter is close to the tube ID (D2 / DN), especially for sizes that are used with several tube wall thicknesses.

Tri Clamp Size Chart

The image below shows how the dimensions correspond to the Tri Clamp flange.

Tri Clamp flange dimensions: tube OD (D1), tube ID (D2 / DN) and flange OD

The table below lists common Tri Clamp sizes and typical dimensions.