The pistons are graphite-coated to reduce friction.活塞上涂了一层石墨以减小摩擦力。Some pistons have seating rings of metal or leather.有些活塞上有金属或皮革的密封环.A pump uses valves and pistons.泵使用阀和活塞....
Detroit Pistons: Walter Herrmann, Allen Iverson, Antonio McDyess, Fabricio Oberto, Rasheed Wallace.底特律活塞队: 赫尔曼, 艾弗森,麦克戴斯, 奥伯托, 拉希德华莱士.The pistons are graphite-coated to reduce friction.活塞上涂了一层石墨以减小摩擦力。Some pistons have s...