1、GB/T33943-20173.2.2.2B型弯曲部分的最小横截面积不得小于无螺纹部分杆径截面积的90%。弯曲部分横截面积按下式计算：A=0.25Dd式中：A。一弯曲部分横截面积：一任意一点较小直径：D与d同一截面的大直径（相隔90）。3.3螺母螺母的型式尺寸见图2和表2。尺寸代号和标注应符合GB/T5276。允许刺造的型式:21530.h110一130。图2表2螺母尺寸单位为毫米螺纹规格DM20(M22)M24(M27)M30(M33)M36(M39)2.52.52.533.53.544max21.623.825.929.132.435.638.942.1min202224273033363
2、9dmin31.433.338.042.846.651.255.960.0min37.2939.5545.2050.8555.3760.566.4471.3max18.019.421.523.825.628.7031.033.40min16.918.120.222.524.327.4029.429.4min13.5014.5016.2018.0019.4021.9023.525.40max0.80.80.80.80.80.80.80.8min0.40.40.40.40.40.40.40.4max3436414650556065min33.035.040.045.049.053.858.863.10.580.630.720.800.871.381.521.643
