管螺紋區(qū)別

1、NPT，PT，G各種螺紋的區(qū)別NPT，PT，G都是管螺紋NPT是National(American)PipeThread的縮寫，屬于美國標(biāo)準(zhǔn)的60度錐管螺紋，用于北美地區(qū)國家標(biāo)準(zhǔn)可查閱國家標(biāo)準(zhǔn)GBT127161991PT是PipeThread的縮寫，是55度密封圓錐管螺紋，屬惠氏螺紋家族，多用于歐洲及英聯(lián)邦國家常用于水及煤氣管行業(yè)，錐度規(guī)定為1:16國家標(biāo)準(zhǔn)可查閱GBT73062000G是55度非螺紋密封管螺紋，屬惠氏螺紋家族標(biāo)記為G代

2、表圓柱螺紋國家標(biāo)準(zhǔn)可查閱GBT73072001另外螺紋中的14、12、18標(biāo)記是指螺紋尺寸的直徑，單位是英行內(nèi)人通常用分來稱呼螺紋尺寸，一等于８分，14就是２分，如此類推G就是管螺紋的統(tǒng)稱(Guan)，55，60度的劃分屬于功能性的，俗稱管圓。即螺紋由一圓柱面加工而成。ZG俗稱管錐，即螺紋由一圓錐面加工而成，一般的水管接頭都是這樣的，國標(biāo)標(biāo)注為Rc公制螺紋用螺距來表示，美英制螺紋用每英寸內(nèi)的螺紋牙數(shù)來表示，這是它們最大的區(qū)別，公制螺紋是

3、60度等邊牙型，英制螺紋是等腰55度牙型，美制螺紋60度。公制螺紋用公制單位，美英制螺紋用英制單位。管螺紋主要用來進(jìn)行管道的連接，其內(nèi)外螺紋的配合緊密，有直管與錐管兩種。公稱直徑是指所連接的管道直徑，顯然螺紋直徑比公稱直徑大。14，12，18是英制螺紋的公稱直徑，單位是英寸螺絲攻牙鉆孔徑對(duì)照表（美制細(xì)螺紋）螺絲攻牙鉆孔徑對(duì)照表（美制細(xì)螺紋）規(guī)格標(biāo)準(zhǔn)徑2級(jí)牙鉆孔徑（UNF）最大最小(螺絲牙外徑)No.080(1.524)1.251.305

4、1.182No.172(1.854)1.551.6121.474No.264(2.184)1.851.9121.756No.356(2.515)2.102.1972.025No.448(2.854)2.402.4582.271No.544((3.175)2.702.7402.551No.640(3.505)2.903.0222.820No.836(4.166)3.503.6063.404No.1032(4.826)4.104.1653.

5、963No.1228(5.486)4.604.7244.49614285.505.5885.360516246.907.0356.78238248.508.6368.382716209.9010.0339.729122011.5011.60711.3299161812.9013.08112.751581814.5014.68114.351341617.5017.67817.323781420.5020.67520.27011223.30

6、23.57123.1141181226.506.74626.6891141229.6029.92129.4641381232.8033.09632.6391121236.006.27135.814V瓦斯桶凡而用JISB8245655326C薄銅電線管用JISB020480螺紋對(duì)照螺紋對(duì)照NPT：National(American)PipeThread的縮寫UN：美國統(tǒng)一螺紋代號(hào).U(UNIFIED)N(NATIONAL).UNR：美國統(tǒng)

7、一螺紋外螺紋.要求外螺紋的牙底為圓弧形狀并且牙底圓弧半徑不小于0.108P則在美國統(tǒng)一螺紋代號(hào)后加注字母“R“.以下是新舊對(duì)照表，可以參考：GB730687GB730787GBT1271691(55牙型角)(55牙型角)(60牙型角)圓錐圓柱圓錐現(xiàn)行標(biāo)準(zhǔn)編號(hào)螺紋種類螺紋代號(hào)內(nèi)螺紋內(nèi)螺紋外螺紋圓柱內(nèi)、外螺紋圓錐內(nèi)、外螺紋螺紋標(biāo)準(zhǔn)代號(hào)RcRPRGNPTGB4459.184中的螺紋代號(hào)ZGGZGGZ螺絲攻牙鉆孔徑和滾絲徑對(duì)照表公制粗螺紋美制粗

8、螺紋2級(jí)牙鉆孔徑2級(jí)牙鉆孔徑規(guī)格標(biāo)準(zhǔn)徑最大最小規(guī)格（UNC）標(biāo)準(zhǔn)徑最大最小M1.00.250.750.7850.729NO.164(1.854)1.551.5821.425M1.10.250.850.8850.829NO.256(2.184)1.801.8711.695M1.20.250.950.9850.985NO.348(2.515)2.102.1461.941M1.40.31.101.1421.075NO.440(2.845)2.

9、302.3852.157M1.60.351.251.3211.221NO.540(3.175)2.602.6972.487M1.70.351.351.4211.321NO.632(3.505)2.802.8952.642M1.80.351.451.5211.421NO832(4.166)3.403.533.302M2.00.41.601.6791.567NO.1024(4.826)3.903.9623.683M2.20.451.751.

10、8381.713NO.1224(5.486)4.504.5974.344M2.30.41.901.9791.86714205.105.2574.979M2.50.452.102.1382.013516186.606.7316.401M2.60.452.202.2382.11338168.008.1537.798M3.00.52.502.5992.459716149.409.559.144M3.00.62.402.4402.2801213

11、10.8011.02310.592M3.50.62.903.0102.8509161212.2012.44611.989M4.00.73.303.4223.242581113.6012.86813.386M4.00.753.253.3263.106341016.5018.84016.307M4.50.753.803.8783.68878919.5019.76119.177M5.00.84.204.3344.134122.2022.606

12、21.971M5.00.94.104.1703.930118725.0025.34924.638M6.01.05.005.1534.917114728.2028.52427.813M7.01.06.006.1535.917138630.8031.11530.353M8.01.256.806.9126.647112634.0034.29033.528M9.01.257.807.9127.647134539.5039.82738.964M1