Threaded & Socket Welded Steel Fittings - Pressure Classes vs. Schedules

Pressure classes, schedules and weights of pipes for threaded & socket welded fittings. Provides reference data for standard (STD), extra strong (XS), and double extra strong (XXS) schedules across different pressure classes.

Pipe Schedule and Designation

Threaded fittings are available in pressure classes 2000, 3000 and 6000.

Socket-welded fittings are available in pressure classes 3000, 6000 and 9000.

Legend

  • Standard (STD) - Standard wall thickness
  • Extra Strong (XS) - Extra strong wall thickness
  • Double Extra Strong (XXS) - Double extra strong wall thickness
  • Schedule - Numbers assigned to different wall thickness of pipe (i.e. schedule 80)
Pressure Class2000300060009000
Threaded Fittings80/XS160XXS
Socket-welded Fittings80/XS160XXS