英制螺纹标准对照表

1、英制,公制螺纹对照表尺寸代号每英寸牙数螺距螺纹直 径（ in）np大径D 、 d小径D1 、 d11/16280.9077.7236.5611/8280.9079.7288.5661/4191.33713.15711.4453/8191.33716.66214.951/2141.81420.95518.6315/8141.81422.91120.5873/4141.81426.44124.1177/8141.81430.20127.8771112.30933.24930.2911-1/8112.30937.89734.9391-1/4112.30941.9138.9521-1/2112.309

2、47.80344.8451-3/4112.30953.74650.7882112.30959.61456.6562-1/4112.30965.7162.7522-1/2112.30975.18472.2262-3/4112.30981.53478.5783112.30987.88484.9263-1/2112.309100.3397.3724112.309113.03110.0725112.309138.43135.4726112.309163.83160.872注： 1in=25.4mm1 、用螺纹密封的管螺纹其标记及各种螺纹的特征代号规定如下：Rc 圆锥内螺纹55 度Rp 与圆锥外螺纹配合

3、的圆柱内螺纹R一圆锥外螺纹标准规定将螺纹尺寸代号写在特征代号之后，若螺纹为械旋应再加写左旋代号LH ,具体示例如下：圆锥内螺纹：Rc1/2左旋圆柱内螺纹：Rp1/2 LH圆柱内螺纹与圆锥外螺纹的配合：Rp2/R2左旋B级外螺纹：G1/2B LH螺纹副G1/2G1/2A内螺纹：G1/2英制螺纹标准 JIS B 0203,JIS B 2301 (mm)# 0 1.52# 1 1.85# 2 2.18# 3 2.51# 4 2.84# 5 3.18# 6 3.51# 7 3.84# 8 4.17# 10 4.83# 12 5.48 1/4 6.35 UNS是英制普通粗牙螺纹；UNF是英制航空标示皆将

4、分母为8,再直接称分子之番号.Ex: 1/8 x 0.50- PPB: 1 分牙螺丝 x 0.50" 长，PPBEx: 5/16 x 0.50- PPB = 2.5/8 x 0.50-PPB : 2 分半牙螺丝 x 0.50 ” 长,PPBEx: 5/32 x 0.50- PPB =1.25/8 x 0.50-PPB: 1 分 2 厘半螺丝 x 0.50 ” 长，PPBEx: 1/4 x 0.50-PPB= 2/8 x 0.50-PPB: 2分牙螺丝 x0.50” 长,PPB注：有时会标示粗牙或细牙.UNF:细牙：电子业较常用.UNC粗牙：重机械结本较常用.Ex: 3/8 x 0.5

5、0 ,UNF - PPB: 3 分细牙螺丝 x 0.50" 长，PPB.C-2: Length Code:为英寸标示，须乘以25.40换算为mm.用扣规量，与公制牙型吻合是公制螺纹，与英制螺纹吻合是英制螺纹。也可以用卡尺量螺纹的外径，和螺距。公制螺纹外径是以毫米为单位，如 6, 8, 10, 12, 18, 20毫米等等螺距也是以毫米 为单位，如0.5,0.75,1,1.5,2,3, 等等英制螺纹外径是以英寸为单位，(每英寸等于25.4毫米)如3/16,5/8,1/4,1/2,等等所以用公制卡尺量外径读数常带不规则的小数。英制螺距是用每英寸含多少个牙表示。把卡尺定在25.4毫米，把一

6、个尺尖对齐螺纹 牙尖，另一个尺尖如对齐螺纹牙尖就是英制螺纹，如对不齐螺纹牙尖应该是公制螺纹。测量螺距时最好把螺纹的牙尖倒印在白粉笔上，粉笔上的印比较清晰，便于测量。测公制螺距应该测量一段长度，如10, 15, 20,毫米等等，数一下含多少牙，算出螺距用英寸为单位规定螺纹规格的为英制螺纹，如：G1"。用公制单位毫米规定螺纹规格的为公制螺纹。如：M30英制是一英寸（24.5厘米）内有多少牙来定的，一般是55度角.公制是两牙尖的间距 是多少MMfc定的螺距,英制粗牙螺纹标准螺触尺寸下孔彳空欺合A歹|J（硬材 ）B歹U（精:材 ）A列直彳空B列直彳空70.7内螺最小彳空83.0内螺触最大 彳

7、空W 1/82.62.570.088.33/163.73.678.485.870.088.31/45.15.076.983.070.588.35/166.66.574.099.570.188.43/88.07.975.080.069.588.27/169.49.373.780.069.088.81/210.710.573.881.269.088.29/1612.312.073.484.469.088.25/813.713.573.580.369.688.53/416.716.572.378.469.688.37/819.519.375.480.970.188.4122.422.073.883.

8、671.088.21 1/825.024.876.981.372.088.41 1/428.328.074.380.772.088.41 3/830.530.381.685.373.888.61 1/233.833.579.384.873.888.61 5/836.035.781.185.774.888.31 3/439.239.080.783.874.888.31 7/841.841.580.684.774.788.4245.044.780.2；84.474.788.4英制管用螺纹标准管用螺触尺寸JIS B 0203JIS B 2301管内螺触Rc(PT)平行内螺触Rp(PS) 管内螺触言十

9、算值下孔彳空言十算值下孔彳空言十算值下孔彳空1/166.2306.26.4906.5一一1/88.2358.28.4958.58.1918.21/410.94110.911.34111.410.94510.93/814.42814.414.84614.914.38814.41/217.9501818.48918.517.943183/423.3492323.9752423.30523129.4232930.1113029.353291 1/437.9403838.7723937.890381 1/243.8334444.5654543.72043255.4125556.4765655.4065

10、52 1/270.7017172.0097270.78870383.2018384.7098583.364833 1/295.5479697.1559795.747954107.834108109.855110108.3221085133.110133135.255135133.5971336158.510159160.655161158.8101587183.360183185.9541868208.560209211.3542129233.960234236.75423710259.166259262747310312.875313英制管螺纹对照表-一英制锥管螺纹对照表 公称直径 螺距低孔直径 低孔深度G