Metric thread hydraulic fittings is most popular type of fluid connectors in the worldwide. In Germany, metric thread of DIN 2353 and ISO 8434 standard tube compression fittings with 24 degree cone connector; Metric thread of DIN 7631 60 degree cone fittings; Metric thread of DIN 20078 series hose fittings, metric thread of DIN 74233 and 74234 45 degree cone fittings; In Japan, Metric thread of Komatsu fittings with 60 degree flare hose adapters JIS B2070, Metric thread of ORFS fittings; In France, Metric thread of flat face fittings used by hanomag, French G GAZ and millimetric fittings.
Metric Tapered/Parallel Thread Type
Metric thread type is most common in Europe. It has a cylindrical inner and outer diameter precise in millimeters. The fine taper of metric tapered thread allows for the best possible force transmission. In writing, you can identify metric threads by a capital “M” plus an indication of their nominal outside diameter (ex. M22 x 1.5). Lastly, when measuring pitch size make sure you’re using a metric pitch gauge.
p = pitch of the thread
d = depth of the thread
r = radius at the top and bottom of the threads
then:
d = 0.61344 p
r = 0.14434 p