英制螺紋標準JISB0203,JISB2301

(mm)

#01.52

#11.85

#22.18

#32.51

#42.84

#53.18

#63.51

#73.84

#84.17

#104.83

#125.48

1/46.35

UNS是英制一般粗牙螺紋;UNF是英制航空

標示皆將分母為8,再直接稱分子之番號.

Ex:1/8x0.50–PPB:1分牙螺絲x0.50”長,PPB

Ex:5/16x0.50–PPB=2.5/8x0.50-PPB:2分半牙螺絲x0.50”長,PPB

Ex:5/32x0.50–PPB=1.25/8x0.50-PPB:1分2厘半螺絲x0.50”長,PPB

Ex:1/4x0.50-PPB=2/8x0.50-PPB:2分牙螺絲x0.50”長,PPB

注:有時會標示粗牙或細牙.

UNF:細牙:電子業(yè)較常見.

UNC:粗牙:重機械結(jié)構較常見.

Ex:3/8x0.50,UNF–PPB:3分細牙螺絲x0.50”長,PPB.

C-2:LengthCode:

為英寸標示,須乘以25.40換算為mm.

用扣規(guī)量,與公制牙型吻合是公制螺紋,與英制螺紋吻合是英制螺紋。

也能夠用卡尺量螺紋外徑,和螺距。

公制螺紋外徑是以毫米為單位,如6,8,10,12,18,20毫米等等螺距也是以毫米為單位,如

0.5,0.75,1,1.5,2,3,等等

英制螺紋外徑是以英寸為單位,（每英寸即是25.4毫米）如3/16,5/8,1/4,1/2,等等所以用公制卡尺量外徑

讀數(shù)常帶不規(guī)則小數(shù)。

英制螺距是用每英寸含多少個牙表示。把卡尺定在25.4毫米,把一個尺尖對齊螺紋牙尖,另一個尺尖如對

齊螺紋牙尖就是英制螺紋,如對不齊螺紋牙尖應該是公制螺紋。

丈量螺距時最好把螺紋牙尖倒印在白粉筆上,粉筆上印比較清楚,便于丈量。測公制螺距應該丈量一

段長度,如10,15,20,毫米等等,數(shù)一下含多少牙,算出螺距

用英寸為單位要求螺紋規(guī)格為英制螺紋,如:G1"。用公制單位毫米要求螺紋規(guī)格為公制螺紋。如:

M30。

英制是一英寸(24.5厘米)內(nèi)有多少牙來定,通常是55度角.公制是兩牙尖間距是多少MM來定螺距,

英制粗牙螺紋標準螺紋尺寸下孔徑嵌合率A列(硬材質(zhì))B列(軟材質(zhì))A列直徑B列直徑內(nèi)螺紋最小徑內(nèi)螺紋最大徑W1/82.62.570.783.070.088.33/163.73.678.485.870.088.31/45.15.076.983.070.588.35/166.66.574.099.570.188.43/88.07.975.080.069.588.27/169.49.373.780.069.088.81/210.710.573.881.269.088.29/1612.312.073.484.469.088.25/813.713.573.580.369.688.53/416.716.572.378.469.688.37/819.519.375.480.970.188.4122.422.073.883.671.088.211/825.024.876.981.372.088.411/428.328.074.380.772.088.413/830.530.381.685.373.888.611/233.833.579.384.873.888.615/836.035.781.185.774.888.313/439.239.080.783.874.888.317/841.841.580.684.774.788.4245.044.780.284.474.788.4英制管用螺紋標準

管用螺紋尺寸JISB0203JISB2301錐管內(nèi)螺紋Rc(PT)平行內(nèi)螺紋Rp(PS)錐管內(nèi)螺紋計算值下孔徑計算值下孔徑計算值下孔徑1/166.2306.26.4906.5－－1/88.2358.28.4958.58.1918.21/410.94110.911.34111.410.94510.93/814.42814.414.84614.914.38814.41/217.9501818.48918.517.943183/423.3492323.9752423.30523129.4232930.1113029.3532911/437.9403838.7723937.8903811/243.8334444.5654543.72043255.4125556.4765655.4065521/270.7017172.0097270.78870383.2018384.7098583.3648331/295.5479697.1559795.747954107.834108109.855110108.3221085133.110133135.255135133.5971336158.510159160.655161158.