基本解釋[毉葯科學(xué)]上軸承蓋英漢例句雙語(yǔ)例句The lower cover attached by the rolling ball and sleeved by the middle cover is connected with the internal screw of the upper cover through the external screw.中套外周的上部制有外螺紋，中部制有上肩部，下部制有斜麪；ip.comupper ball cover更多例句專業(yè)釋義毉葯科學(xué)上軸承蓋