root penetration

美英加陆军规格_馆档网 ... "根间隙(熔接)"," root opening" "熔透量"," root penetration" "齿底面"," root surface" ...

直角三角形_馆档网 ... "熔接根"," root of weld" "根深透(熔接)"," root penetration" "根半径(熔接)"," root raduis" ...