对焊异径法兰? asme b16.5-2013中有相关描述,table 6, note 4: (4) for method of designating reducing threaded and reducing slip-on flanges, see para. 3.3 and examples below. examples: (1) the size designation is nps 6 x 2 1 2 — class 300 reducing threaded flange. this flange has the following dimensions: nps 2 1 2 p taper pipe thread tapping (asme b1.20.1) 320 mm p diameter of regular nps 6 class 300 threaded flange 35 mm p thickness of regular nps 6 class 300 threaded flange 178 mm p diameter of hub for regular nps 5 class 300 threaded flange. hub diameter may be one size small to reduce machining. in this example, a hub diameter of nps 2 1 2 would be the smallest acceptable. 15.5 mm p height of hub for regular nps 5 class 300 threaded flange (2) the size designation is nps 6 x 2 — class 300 reducing threaded flange. use regular nps 6 class 300 blind flange tapped with nps 2 taper pipe thread (asme b1.20.1). 查看更多