请问这句话什么意思? the pump manufacturer’s standard nozzles (bored and tapped) with parallel thread may be used for sizes 1 1/2 inches and smaller. threaded connections shall not be used. flanged nozzles shall be used for pipe sizes of 2 inches and larger. 泵制造厂家生产的带有直螺纹的标准接管可用于连接尺寸小于等于1 1/2英寸的管口。禁止使用螺纹连接。尺寸大于等于2英寸的管口应使用法兰连接接管。查看更多