Reading Reducing Fittings

A variety of types most commonly required for piping systems are illustrated on this page. In these illustrations, each opening of the fitting is identified with a letter which indicates the sequence to be followed in reading the size of the fitting.

In designating the outlets of reducing fittings, the openings should be read in the order indicated by the sequence of the letters "A", "B", "C", and "D". The following information is based on ASME B16.11 and MSS SP-106.

Tee Reducing on outlet (1 x 1 x 3/4)	Tee Reducing on one run (1 x 3/4 x 1)	Tee Reducing on one run and outlet (1 x 3/4 x 3/4)	Tee Reducing on both run (bullhead) (3/4 x 3/4 x 1)
Cross Reducing on one outlet (1 x 1 x 1 x 3/4)	Cross Reducing on both outlets (1 x 1 x 3/4 x 3/4)	Cross Reducing on one run and outlets (1 x 3/4 x 1 x 3/4)	Cross Reducing on one run and both outlets (1 x 3/4 x 3/4 x 3/4)
Lateral Reducing on branch (1 x 1 x 3/4)	Lateral Reducing on one run (1 x 3/4 x 1)	Lateral Reducing on one run and branch (1 x 3/4 x 3/4)	Elbow Reducing elbow (1 x 3/4)