ASTM A234 WP91 Pipe Fittings are made up of a chromium molybdenum alloy like all A234 specification pipes with the molybdenum content ranging from 0.85% to 1.05% and the chromium content between 8 and 9.5%. The Alloy Steel WP91 Buttweld Fittings are most common in this range and they are stronger and easy to weld with. The sizes range between ½ inches to 24 inches in outer diameter.
ASTM A234 WP91 Pipe Fittings
The wall thickness of the fittings range greatly and the schedules range from 5 ton XXS corresponding to the wall thickness, diameter and the pressure containment capacities as well. The ASTM A234 Gr WP91 Elbow is one of the most used fittings in this range. Elbows are fittings that are used to turn the direction of the pipes usually by 90 degree angle but there are others as well.
The elbows could be short, long or custom radius in types. The Alloy Steel A234 WP91 Reducer is another most used type in this range of fittings. The reducer as the name indicates is used to reduce the volume of the flow. The SA234 WP91 90 Degree Elbow is stronger than the WP22 elbow. The Alloy Steel WP91 Tee is used to divide the pipes into two branches.
Alloy Steel WP91 Buttweld Fittings Specification format
½” NB to 24″ NB in Sch 10s, 40s, 80s, 160s, XXS. (DN6~DN100)
Seamless ButtWeld Fitting: From 1/2″ - 10″
Welded ButtWeld Fitting: From 1/2″ - 48″
Precautions are taken after Heat treatment
After forming at an elevated temperature, WP91 Fittings are cooled to a certain temperature below the critical range under appropriate conditions to prevent from injurious defects caused by too rapid cooling, but not in any case it should cool rapidly in still air.
Pressure Rating of Alloy Steel A234 WP91 Reducer
Most commonly used ASTM A234 WP91 Pipe Fittings Types