Type C - male
Type D - female with d4 = d3
Type G - female with d4 > d
DIN 6319 Spherical washers, Steel, Male or Female
These spherical washers are used for clamping on non-parallel surfaces or between parts with uneven or irregular faces.
Female washers Type G are mainly used on elongated holes.
When utilising hexagon nuts with spherical seating DIN 6330 the male washer is redundant.
Type C/D Case hardening steel, case hardened all round depth 0,2 to 0,4 mm, hardness (550 + 100) HV 10
Type G Heat-treatable steel, tempered, hardness (350 + 80) HV 30
Also available in stainless steel.