An automatic pump in which a large volume of water flows through a valve that it periodically forces shut, the sudden pressure change being used to raise a smaller volume of water to a higher level.
- ‘Under this method the head of the crane is raised by means of a hydraulic ram so as to create a gap between the head of the crane and the mast.’
- ‘A fully active suspension moves each wheel up and down independently, usually by way of high-pressure hydraulic rams.’
- ‘Technicians used a customized hydraulic ram to stress the tendons to a predetermined gauge pressure corresponding to the design jacking force.’
- ‘In February, 2001, hydraulic rams and electric motors that open the bridge will be installed.’
- ‘There is a device called a hydraulic ram, which causes water to flow uphill with no outside influences except the actual flow of water.’