To reduce the effect of water hammer, suction and discharge lines of pumps are often equipped with which of the following?

The correct answer is the option that involves using relief valves and air chambers to mitigate the effects of water hammer. Water hammer is a pressure surge that occurs when a fluid in motion is forced to stop or change direction suddenly, often resulting in shock waves that can damage piping and equipment.

Relief valves serve as safety devices that can open to allow excess pressure to escape, thus preventing the build-up of pressure that can contribute to water hammer effects. Meanwhile, air chambers act as cushioning devices. They contain air, which is compressible and can absorb sudden surges of pressure when the fluid flow is abruptly altered. This combination helps to smooth out the pressure spikes that occur, ensuring a more stable operation of the piping system.

Using just check valves would not provide adequate protection against water hammer since they primarily prevent backflow but do not address issues related to sudden pressure changes. Flow meters also do not contribute to the mitigation of water hammer; they are used for measuring flow rates rather than controlling or cushioning pressure surges. Expansion tanks can help in absorbing thermal expansion but are not typically used to manage transient pressures caused by water hammer. Hence, incorporating relief valves and air chambers offers a comprehensive approach to managing the forces generated by water hammer.