What is a valve that connects a customer's service to the water main called?

The term for a valve that connects a customer's service line to the water main is known as a corporation cock. This valve plays a critical role in the water distribution system as it allows for the control of water flow from the main supply line into the service line that provides water to residential or commercial properties.

A corporation cock is typically installed directly at the water main and is essential for activating or deactivating the flow of water to a customer’s service connection. It is often used by utilities for maintenance or emergency shut-offs, which is crucial for ensuring the system's integrity and safety. Understanding this component is vital for anyone involved in water distribution and management, as it directly impacts both service reliability and system maintenance.

Other types of valves mentioned serve different functions: a tap valve is often associated with installation of taps into pipelines, a ball valve is typically used for regulating flow in many applications due to its ease of use and reliability, and a check valve is primarily designed to prevent backflow in plumbing systems. Each of these valves has its own specific applications and is not used specifically to connect customer service lines to the main supply.