What is the primary usage of a gate valve in a water distribution system?

A gate valve is primarily used for isolation in a water distribution system. This type of valve is designed to either fully open or fully close the flow of water, which allows operators to isolate a section of the pipe for maintenance, repair, or other operational purposes. The gate valve provides very little resistance to flow when fully open, making it suitable for applications where the flow needs to be stopped or started, rather than regulated.

In contrast, flow regulation typically requires a valve that can precisely control the flow rate, such as a globe valve. Pressure control involves regulating the pressure within the system, which again requires different types of valves, like pressure-reducing valves. Backflow prevention is concerned with stopping the reverse flow of water, necessitating devices that are designed specifically for that purpose, such as check valves or backflow preventers. Therefore, the primary function of a gate valve is isolation, allowing other components of the distribution system to be serviced without disrupting the entire system.