短語詞組短語bolt -hole corner crack 螺栓孔角裂紋Bolt -hole fits 釘孔配合threaded bolt -threaded hole 螺紋螺栓flange -bolt-hole 法蘭螺栓孔four -bolt hole pattern 四螺栓孔結(jié)構(gòu) 返回 bolt-hole