Mill Test Report or MTR is documentation from a testing facility that usually shows the chemical makeup and physical strength/properties of materials required to meet certain ASME and ASTM grades
Phosphorus has four major effects on iron: increased hardness and strength, lower solidus temperature, increased fluidity, and cold shortness
The raised face flange provide a relatively large contact area. Where metal gaskets are used with this facing, the gasket area should be reduced to increase the gasket compression.
Large bore piping divided to 3 types
a- standard schedule(thickness 4.75mm to 9.53mm)
b- high schedule(thickness 9.54mm to 19mm)
c- critical schedule(thickness more than 19mm)
Each type different in the shape of welding groove