HG/T 21635-1987 (English Version) PDF

Scope: This standard applies to seamless butt welded pipe fittings made of carbon steel and low alloy steel. It includes four types of tees (equal diameter and reducing diameter), 90° elbows (long radius and short radius), reducers (concentric and eccentric) and pipe caps, divided into two series: metric and imperial. According to the current domestic production and use conditions, the diameter range of these four pipe fittings is determined as: equal-diameter tee, reducing tee main pipe; 90° elbow; concentric reducer, eccentric reducer big end; pipe cap The nominal diameter is 50~600mm (2″~24″), and the minimum nominal diameter of the branch pipe of the reducing tee is half of the nominal diameter of the big end. The nominal pressure of metric pipe fittings is divided into four levels: PN25, 40, 64, and 100kgf/cm2 (i.e. 2.5MPa, 4.0MPa, 6.4MPa, and 10MPa). The thickness of the wall is calculated based on the allowable stress of the material [σ] = 1310kgf/cm2, and the medium corrosion margin is 1.5mm. The British pipe fittings nozzle number (Schedule Number abbreviated as Sch××) is divided into Sch40, Sch80 and Sch160 blue types. The units used in this standard are: length is mm (except when noted in cm), pod size: pressure is kgf/cm^(2) (1kgf/cm^(2)≈O.1MPa); weight is kg. The thickness of the pipe joints of all pipe fittings is shown in the pipe fitting specification table. If the orderer has special requirements, please provide them separately.

HG/T 21635-1987 history

1987 HG/T 21635-1987 Carbon steel, low alloy steel seamless butt welding pipe fittings