1. Nomenclature and Terminology
– **United Kingdom**: “Tap” refers to valves controlling water supply in bathtubs and sinks.
– **United States**: “Faucet” is the primary term for water dispensing fixtures; “tap” is also used.
– **Spigot**: Commonly used by plumbers for outdoor fixtures.
– **Silcock/Bibcock**: Terms for fixtures that penetrate foundations, often freeze-resistant.
– **Tap Water**: Refers to purified water for domestic use; single temperature taps are common in public restrooms.
2. Types of Taps and Valves
– **Liquid Taps**: Plastic taps prevalent in India due to affordability.
– **Mixer Taps**: Combine hot and cold water; invented by Thomas Campbell in 1880.
– **North American Style**: Features a center handle for flow and temperature control.
– **Pressure Balancing**: Ensures stable hot/cold mixture during pressure changes to avoid scalding.
– **Gas Taps**: Specialized ball valves for controlling fuel gas release in various applications.
– **Globe Valves**: Require maintenance due to wear on washers and valve seats; not maintenance-free.
– **Gate Valves**: Metal wedge design; minimal flow resistance when open; wheel-shaped handle common in the UK.
– **Cone and Ball Valves**: 90° motion; cone valve known as taper-plug cock in UK; ball valve uses spherical ball for flow control.
3. Mechanisms and Technologies
– **Flow Adjustment**: Water and gas taps allow adjustable flow; gate valves provide progressive control, ball valves for coarse control.
– **First Mechanism**: Screw-down tap patented by Guest and Chrimes in 1845.
– **Washer Type**: Older taps use rubber/neoprene washers for leak-proof seals.
– **Infrared Proximity Sensors**: Emerging technology replacing standard valves; hands-free operation.
– **Foot Controlled Valves**: Used in labs and healthcare; prevents contamination from dirty hands.
– **Aerators**: Limit water flow; introduce air to reduce splashing; creates small droplets.
– **Laminar Flow Devices**: Used in sanitary settings; restrict flow while preventing air introduction.
– **Ceramic and Plastic Taps**: Utilize low friction between surfaces; require less maintenance than traditional valves.
4. Maintenance, Longevity, and Backflow Prevention
– **Globe Valves Maintenance**: Washers can be replaced; valve seat resurfacing possible multiple times.
– **Cartridge Lifespan**: American Standard cartridges offer long lifespan in sediment-free water.
– **Replacement Parts Availability**: Moen cartridges are widely accessible; American Standard cartridges are durable.
– **Backflow Prevention**:
– **US Regulations**: Require vacuum breakers or backflow preventers on hose spigots; prevents contamination.
– **UK Regulations**: Mandate double check valves; often integrated within tap body.
– **Importance**: Protects public and building water systems from pressure drops and maintains safe drinking water standards.
5. Applications and Usage
– **Domestic Water Systems**: High pressure systems can use globe valves; low pressure systems benefit from gate valves.
– **Industrial Applications**: Thermostatically controlled valves automate liquid provision; enhance efficiency.
– **Healthcare Settings**: Foot controlled valves minimize contamination risks; critical for hygiene.
– **Laboratory Usage**: Laminar flow devices preferred for avoiding hazardous bacteria in water.
– **Modern Tap Design**: Focus on user-friendly features and reduced maintenance for residential and commercial use. https://en.wikipedia.org/wiki/Tap_(valve)
