A.承壓面;緊固 B.剪切面;防松 C.剪切面;加壓 D.摩擦面;加壓
A.15mm B.25mm C.20mm D.30mm
A.tmin=120+0.01d B.tmin=100+0.01d C.tmin=100+0.1d D.tmin=120+0.1d