GB/T21359-20083.2.3焊接式套管焊接式套管的尺寸和公差或公差等级（见GB/T1800.4)见图3和表2。0.345R20.2锐边30.140.221.50.2图3焊接式套管表2焊接式套管尺寸单位为毫米颈部外径插口直径外部直径公称尺寸管子外径内径CC9CDNDh11h10h10N11252525.629.233.822.63233.734.338.242.531.3404040.644.749.037.6650.851.656.260.548.66563.564.169.974.060.3576.1.76.782.687.572.98088.989.895.7101.084.9100101.6102.5108.7114.197.63.2.4六角螺母六角螺母的尺寸和公差或公差等级（见GB/T1800.4)见图4和表3。3.2.5圆螺母圆螺母的尺寸和公差或公差等级（见GB/T1800.4)见图5和表4.3.2.6密封圈密封圈尺寸和公差见图6和表5。有关密封圈的技术要求见附录B。3.2.7支撑环支撑环的尺寸和公差见图7和表6。3.3表面粗糙度螺纹接头、套管、螺母和支撑环的表面粗糙度应符合GB/T1031的规定；对于与食品接触的精加工表面，其Ra1um。3
