What characterizes a slow opening valve?

A slow opening valve is characterized by a gradual increase in flow, which is achieved by requiring a minimum of five full turns from the closed position to the fully open position. This gradual opening helps to control the flow rate more effectively, reducing the risk of water hammer or sudden changes in pressure. As the valve is turned, the flow through the valve increases slowly, which is particularly important in systems where maintaining stability is crucial.

This feature makes slow opening valves ideal for applications that demand careful control over fluid dynamics, allowing operators to adjust the flow rate incrementally rather than all at once. This is opposed to instant or quick-opening valves, which can lead to abrupt pressure changes in a system. Therefore, the characteristic of requiring multiple turns ensures that the valve can be opened at the desired rate, thus fulfilling its function in managing fluid flows safely and effectively.