1、螺纹基本尺寸对照表螺纹基本尺寸对照表 （以及螺纹底孔相关尺寸）参照机械设计师首册编制 OPMSM2005年7月螺 纹 代 号 Thread code一、英制螺纹（螺纹牙型角55度）BSW英国标准惠氏螺纹（粗牙）BSF英国标准惠氏螺纹（细牙）G直管螺纹(外螺纹分A、B两级即在螺纹中径公差有所区别，丝锥分G、G-D)非密封性螺纹R锥管外螺纹（旧代号ZG；KG）RC锥管螺纹（旧代号ZG；KG）二、美制螺纹（螺纹牙型角60度） UNC统一制粗牙螺纹（代替NC）UNF统一制细牙螺纹（代替NF）UNEF统一制超细牙螺纹UN统一制不变螺距螺纹UNS统一制特殊螺纹三、美制螺纹（螺纹牙型角60度）NPT一般用途
2、锥管螺纹（旧代号Z、K）（斜角为147即1：16）NPSC管接头直管螺纹NPSM设备上自由配合，机械连接用直管螺纹NPTF干密封锥管螺纹NPSF干密封燃料螺纹NGT气瓶用螺纹四、米制螺纹（螺纹牙型角60度，斜角为14724即1：16）ZM米制锥管螺纹五、其它螺纹SM缝纫机螺纹（螺纹牙型角60度，平顶、螺纹底部为园弧形）PZ气瓶螺纹5V1至20V1气门芯螺纹（螺纹牙型角60度，平顶、螺纹底部为园弧形）六、管螺纹（螺纹牙型角55度，螺纹顶、底部为园弧形约）RC圆锥螺纹（螺纹牙型角55度，斜角为147即1：16）RP圆柱螺纹（螺纹牙型角55度）R圆锥外螺纹（螺纹牙型角55度，斜角为147即1：16）
3、七、普通螺纹（螺纹牙型角60度）M普通螺纹代号八、特殊螺纹Tr梯形螺纹（螺纹牙型角30度）B锯齿形螺纹（牙型角3030度）螺纹公称直径d螺距P钻头直径d铜不锈钢2041616025175175305252503521521540733330535355084142054545614950755252812566671770757172101584851258687169707571721217510110215104105125106107110911142118121512412511291316213814151441451149151825153155215816151641651169
4、172025173175217818151841851189192225193195219820152042051209212432072122182215224225122923非螺纹密封英制英制锥管螺纹英制锥螺纹螺纹直径牙数钻头直径螺纹直径牙数钻头直径螺纹直径牙数钻头直径1/828881/828841/827861/4191171/4191121/4181113/8191523/8191473/8181451/2141891/2141831/2141793/4142443/4142363/41423211130611429711152921-1/4113921-1/4113831-1/41
5、153791-3/8114161-1/2114411-1/21154391-1/211451211558211556螺距(t)螺纹长度基面上螺纹直径牙型高度(h1)有效长度基面长度外径(d)中径(d2)径(d1)0.9194.59.739.158.570.581.3411613.1612.311.450.861.3412616.6615.8114.950.861.81157.520.9619.7918.631.161.81179.526.4425.2824.121.162.31191133.2531.7730.291.482.31221341.9140.4338.951.482.3123144
6、7.8146.3344.851.482.31261659.6258.1456.661.482.313018.575.1973.7172.231.482.313220.587.8986.4184.931.482.313825.5113.03111.56110.081.48本螺纹基面上各直径等于圆柱螺纹的各相应直径基面上螺纹径 d1 = d - 1.28t3/4 = 26.44 - 1.28 * 1.81 = 24.12斜角（）14724 锥角 （2tg)=1:16公称直径（英寸）每英寸牙数（n)螺距(t)管子外径（d)管接头螺纹径（d1)牙型高度(h1)名义尺寸最大外径最小外径名义尺寸最大径最小
7、径 1/8280.919.739.689.388.578.928.670.58 1/4191.3413.1613.112.7411.4511.8411.560.86 3/8191.3416.6616.616.2414.9515.3515.060.86 1/2141.8120.9620.8920.518.6319.0518.751.16 5/8141.8122.9122.8522.4620.5921.0120.711.16 3/4141.8126.4426.3825.9724.1224.5724.251.167/8141.8130.230.1429.7327.8828.3328.011.1611
8、12.3133.2533.1832.7530.2930.7930.431.481-1/4112.3141.9141.8441.3638.9539.4639.11.481-3/8112.3144.3344.2643.7841.3741.8741.511.481-1/2112.3147.8147.7447.2144.8545.4451.481-3/4112.3153.7553.6753.1450.7951.3450.941.482112.3159.6259.5459.0156.6657.2156.811.482-1/2112.3175.1975.1174.5472.2372.8372.391.48
9、3 112.3187.8987.887.1984.9385.5885.11.48外径d由公称直径所决定螺纹径 d1 = d - 1.28t斜角（）14724 锥角 （2tg)=1:16公称直径（英寸）每英寸牙数（n)螺距(t)螺纹长度基面上螺纹直径牙型高度(h1)有效长度基面长度外径(d)中径(d2)径(d1)1/16270.946.54.067.97.146.390.751/8270.9474.5710.279.528.770.751/4181.419.55.0813.5712.4411.311.133/8181.4110.56.117.0615.9314.81.131/2141.8113.
10、58.1321.2219.7718.321.453/4141.81148.6126.5725.1223.671.45111-1/22.2117.510.1633.2331.4629.691.771-1/411-1/22.211810.6741.9940.2238.451.771-1/211-1/22.2118.510.6748.0546.2944.521.77211-1/22.211911.0760.0958.3356.561.77外径d由公称直径所决定牙型高度 h1=0.8t基面上螺纹径 d1 = d - 1.6t3/8 = 17.06mm d1=17.06 - 1.6 * 1.41 = 1
11、4.80斜角（）14724 锥角 （2tg)=1:16公称直径每寸牙数螺距(t)外螺纹外径螺纹径选用钻头名义尺寸最大尺寸最小尺寸名义尺寸最大尺寸最小尺寸3/16241.064.634.54.243.563.973.713.71/4201.276.26.055.754.915.395.15.15/16181.417.787.627.316.346.866.556.53/8161.599.369.28.97.738.297.977.97/16141.8110.9310.7510.459.069.679.339.31/2122.1212.512.311.910.310.9610.6110.59/16
12、122.1214.0813.8713.4711.8912.5612.212.15/8112.3115.6515.4315.0313.2613.9413.613.53/4102.5418.8118.5718.1716.1716.9216.5416.47/892.8221.9621.721.219.0319.8219.4519.5183.1825.1124.8224.3221.822.6722.27221-1/873.6328.2527.9327.3324.4625.4324.991-1/473.6331.4331.0930.4927.6428.5928.181-3/864.2334.5634.2
13、33.630.1331.2330.761-1/264.2337.7337.3636.7633.3134.3833.941-3/455.0844.0243.5942.7938.739.9539.451-7/84.55.6447.1546.6845.8841.2342.5842.0624.55.6450.3249.8449.0444.4145.7945.25螺纹（d）公称直径 3/4=19.05 mm外螺纹（d1） 径 d-1.28 t 3/4=19.05 -1.28 * 2.54=15.79 mm外螺纹（d1） 径 d-1.134 t 3/4=19.05 -1.134 * 2.54=16.16
14、mm公称直径 （英寸）每英寸牙数（n)螺 距(t)外螺纹外径螺纹径名义尺寸名义尺寸d =d-0.075t-0.0511/16141.81417.2815.43/8201.279.388.087/8112.312219.65/8141.8115.6913.823/4122.1218.8416.651/4260.9766.235.241/2161.58712.5310.91102.5425.1522.52螺纹d（公称直径）外螺纹d1=径=d-1.28t 3/4=19.05-1.28*2.116=16.34螺纹d1=径=d-1.134t 3/4=19.05-1.134*2.116=16.653/4=12牙/英寸 t=2.116
