All bilge suction must be fitted with suitable （）, which in the machinery space would be mud boxes positioned at floor-plate level for easy access.

Centrifugal pumps, however, can be designed with a numb...

单项选择题Centrifugal pumps, however, can be designed with a number of impellers （） to attain a large amount of liquid.

Sealing in pump shaft is achieved by means of the （）.A....

单项选择题Sealing in pump shaft is achieved by means of the （）.

（） is the breakdown of surface tension between oil drop...

单项选择题（） is the breakdown of surface tension between oil droplets in an oil water mixture which causes them to join and increase in size.