PVC ball valves are installed in water supply lines for household water lines and sometimes in the gardening water system.
The valve has an inlet in each end for the supply pipe to enter and depending on the valve can be cemented to the pipe and tightened in place with nuts.
The ball itself has a hole itself drilled from through the center which when aligned with the supply pipe allows water to rush through the hole and serve the attached appliances.
Loosening the valve is a quick process but sometimes replacements are also necessary. Silicone lubricant can be used to lubricate the sticky PVC valves.
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