Theoretically the sum of the velocities of the three pistons on the discharge stroke in a low-fluctuation triplex pump should be a constant, and this can be achieved by means of the cam mechanism.是什么意思_Theoretically the sum of the velocities of the three pistons on the discharge stroke in a low-fluctuation triplex pump should be a constant, and this can be achieved by means of the cam mechanism.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句