直螺纹丝头长度及丝数Themanuscriptwasrevisedontheeveningof2021直螺纹丝头长度及丝数直螺纹丝头长度及丝数规格剥肋直径螺纹尺寸丝头长度完整丝扣圈数16±×220~≥818±M19×25~≥720±M21×27~30≥822±M23×~≥925±M26×332~35≥928±M29×337~40≥1032±M33×342~45≥1136±M37×46~49≥940±M41×49~≥10丝头长度是套筒长度的一半希望这对你有帮助GB_T196-2003GB_T197-2003...