positioning key meaning in English

定位键

Three position key
三位式键
( 3 ) the transformation for turbo cycling compressor is designed in both differential pressure seal parts at the inlet and outlet and the connecting construction of the positioning key and turbo cycling compressor casing : replace wave pipe of differential pressure seal parts with asbestos jointing and improve its reliability ; jointing connection of the positioning key and turbo cycling compressor casing has been converted into screw thread connection and avoid the dangers from jointing crack
( 3 )从进出口压差密封部件和定位键与外壳间联接结构两方面入手，提出了相应的改造方案：将机组进出口压差的密封部件由波纹管改为石棉填料函，提高了其运行可靠性；将内件周向定位键与外壳间的联接结构由焊接改为螺纹联接，避免了焊接裂纹引起的安全事故。