Modern bathroom and kitchen taps often use ceramic or plastic surfaces sliding against other spring-loaded ceramic surfaces or plastic washers. These taps exploit the uniquely low value of the coefficient of friction of 2 ceramic surfaces in contact, especially in the presence of water as a lubricant. These taps tend to require far less maintenance than traditional globe valves, and when maintenance is required the entire interior of the valve is usually replaced, often as a single pre-assembled cartridge.
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