Final answer:
The correct type of valve for throttling action is the b) globe valve. These are specifically designed to adjust fluid flow with precision, making them ideal for tasks requiring fine control of flow rates.
Step-by-step explanation:
The question is about which type of valve is used for throttling action. Throttling is the process of regulating the flow or pressure of a fluid by partially obstructing its flow path. In the context of valves, this action is crucial in many applications where precise control of fluid flow is necessary.
Let's examine the options provided:
- Check valves are designed to allow fluid to flow in one direction only, hence not suitable for throttling.
- Globe valves are designed with a stem that moves up and down to restrict flow, making them very good for throttling because they offer fine control over the flow.
- Butterfly valves can throttle flow, but they are not as precise as globe valves. They are better suited for quick open or close applications.
- Gate valves are designed primarily for on/off control with minimal pressure drop, and are not ideal for throttling because they do not allow for fine control.
Considering the options, the correct choice for valves used for throttling action is b) globe valves. They have a design that permits accurately controlling flow rates with their ability to make fine adjustments.