1, Q235 elbow manufacturing standards: GB (GB), American Standard (ANIS), Japanese Standard (JIS), British standard (BS), German standard (DIN), Italy superscript (UNI) and so on. 2, Q235 elbow according to production methods can be divided into: push the system, pressing, forging, casting and so on. 3, Q235 bend radius of curvature according to points: can be divided into long radius elbows and short radius elbows. Long radius elbow refers to its radius of curvature equal to 1.5 times the diameter of the elbow, that is R = 1.5D. Short radius elbow refers to its radius of curvature equal to 1.0D elbow diameter, ie R = 1.0D. (D is the diameter elbow, R is the radius of curvature). 4, Q235 elbow pressure levels according to points: Approximately seventeen species, and the US standard pipe is the same, there are: Sch5s, Sch10s, Sch10, Sch20, Sch30, Sch40s, STD, Sch40, Sch60, Sch80s, XS; Sch80, SCH100, Sch120, Sch140, Sch160, XXS; one of the most common STD and Sch40 are two kinds. 5, Q235 elbow divided by angle: 45 ° and 90 ° 180 ° three most commonly used, according to project needs in addition also includes other non-normal 60 ° angle bend. 6, elbow elbow versatile product applications are mainly used in petroleum pipeline, gas pipeline projects, chemical plants, power plants, shipyards, mechanical equipment, pharmaceuticals, dairy, beer, beverage, water and so on.