短語詞組短語overhead back downward pull 過頂後下拉back -pull wire-drawing 反拉力拉絲back pull drawing 後張力拉伸;後推力拉伸back pull force 反拉力back pull wire drawing 後拉力拔絲法back pull stress 逆應(yīng)力Back pull pattern 後拉式 返回 back pull