Malleable Iron Pipe Fittings Pressure Rating

Bs 143 1256 1986 states that fittings are for general purposes for the transmission of fluids within the pressure and temperature ranges specified.
Malleable iron pipe fittings pressure rating. They are made for light industrial and plumbing use up to 300 psi. The pressure rating roughly of a 150 pound malleable iron fitting is 150 psi 300 pound malleable iron fitting has a pressure rating of 300 psi. Pressure ratings pressure ratings of pipes and tubes and their fittings carbon steel stainless steel plastic copper and more. Malleable iron fittings are lighter fittings in 150 and 300 pressure class.
Threading identification marking class 300 malleable iron threaded fittings are marked with the numerals 300 the letters mi and the size. Malleable iron threaded fittings pressure temperature ratings class 150 class 300 nps normal pipe size 1 4 1 11 4 2 2 1 2 3 temp c temp f bar psi bar psi bar psi bar psi. Please note that although products are designed using the asme b16 3 standard which have a pressure rating of 300 psi fm approval is only for up to 175 psi and there are no temperature range requirements specified by the fm1920 standard. Pressure temperature ratings.
Class 150 malleable iron threaded fittings have no pressure class markings. Again it s a little more complicated you have to look at the fluid and the temperature because the pressure is related to temperature. Cast iron there are four basic types of cast iron white iron gray. Pressure ratings pressure ratings of pipes and tubes and their fittings carbon steel stainless steel plastic copper and more.
A class 150 rating means these fittings have been tested and approved for a maximum pressure of 300 psi at 150 f. Asme b 16 39 malleable iron threaded pipe unions threads. Ansi asme b1 20 1 pipe threads. The graph below shows the bs pressure temperature.
150 black galvanized malleable iron pipe fittings meets or exceeds all applicable astm and ansi standards stocked from 1 8 through 6 diameters 100 pressure tested before leaving the factory. As the temperature goes up the pressure goes down. Some malleable fittings such as floor flange lateral street tee and bullhead tees are not commonly available in forged iron. Bsi pipe tube and fittings standards and specifications british.
Asme ansi b16 standards for pipes and fittings the asme b16 standards covers pipes and fittings in cast iron cast bronze wrought copper and steel.