短语词组短语screw -type gas compressor 螺杆式瓦斯压缩机Screw -type air compressor 螺杆式空压机open -type screw refrigerating compressor 开启式螺杆制冷压缩机positive -displacement screw type compressor 正排量螺旋式压气机 返回 screw-type compressor