压缩机的排气量The discharge of the compressor 采用一台大的总比采用两台小的经济...
未知题型压缩机的排气量The discharge of the compressor 采用一台大的总比采用两台小的经济It is cheaper to have one big one than two small ones 备用台数也不宜多,一般为3~4开1备。The number of spare sets should not be more, generally 3 ~ 4 open 1 ready.