Radius Cut Grooving Dimensions – Ductile Iron Pipe

AWWA Ductile Iron Pipe

Gasket Seating Surface (A):

The same coupling can be used either as a rigid joint or a flexible joint depending on the groove.  Gasket seat “A Rigid” is for rigid joints and Gasket seat “A Flex.” for flexible joints.

The gasket seating surface shall be free from deep scores, marks, or ridges that could prevent a positive seal.

Groove Diameter (C):

The “C” diameters are average values.  The groove must be of uniform depth around the entire pipe circumference.

Radius (R):

The groove must be cut with a radius ‘R’ at the corners of the groove to reduce stress concentration.

Minimum Wall Thickness (t):

“T” is the minimum allowable wall thickness that may be cut-grooved; tolerances are to conform to ANSI/AWWA C151/ A21.51.