Positive SSL
1 某雙線螺紋之螺距為P,導程角為 ,節圓直徑為D,則下列何者正確?
A `tanθ =(2P)/(πD)`
B `tanθ =(P)/(πD)`
C `tanθ =(πD)/(2P)`
D `tanθ =(πD)/P`
`tan =L/(πD)` = `(2P)/(πD)`(雙線螺紋之導程為螺距之二倍)