Valve is a mechanic device which is used to connect, cut off, and regulate the medium flows in pipelines. Valve includes butterfly valves, wafer butterfly valves, soft seal butterfly valves, hard seal butterfly valves, flange butterfly valves, soft seal gate valves, hard seal gate valves, non rising stem gate valves and rising stem gate valves, check valves, wafer check valves, swing type check valves, lifting type check valves, rubber disc check valves, ball type check valves, foot valves, bellows seal globe valves, soft seal ball valves, hard seal ball valves, welded ball valves, one piece ball valves, two piece ball valves, three piece ball valves, full port ball valves, reduced bore ball valves, hydraulic control valves, multi functional pump valve, pressure relief valves, grooved fire protection valves,etc. Most of them can be used in water, oils, gas pipeline systems, today we are going to talk about how to select a right valve for water supply system, and where a valve should be installed in water supply system:
How to choose a right valve for water supply system?
1. when the pipe diameter of the water supply system is not greater than 50mm, a globe valve should be used; when the pipe diameter of the water supply system is larger than 50mm, gate valve and butterfly valves should be installed;
2. When the flow rate and water pressure need to be adjusted, a regulating valve or a bellows sealing globe valve(also known as stop valve) should be used;
3. For water pipeline systems where the resistance of water flow is small(such as on the suction pipe of the water pump), a gate valve(also known as sluice valve, brake valve, discharge gate valve,etc) can be used;
4. Gate valves and butterfly valves should be used on the pipe sections where the water flow needs to flow in both directions, and globe valve(stop valve) should not be used;
5. For parts with small installation space in pipelines, butterfly valves and ball valves should be used;
6. On pipe sections which are often opened and closed, stop valve(also called globe valves) should be used, like a bellows globe valve,or bellow seal globe valve;
7. Water control valves( or called hydraulic control valves) should be used on the outlet pipes of water pumps with larger diameters;
Where a valve should be installed in water supply system?
1. a valve should be installed in the introduced pipe section which connect the municipal water supply pipeline to the water pipeline of the residential area;
2. The nodes of the outdoor annular pipe network in the residential area shall be installed with a valve according to the separation requirements. When the annular pipe section is too long, valves should be installed sectionally;
3. A valve should be installed in the start of the branch pipe connected from the main water supply pipe of the residential area or the start of the household pipe;
4. A valve should be installed in household pipe, water pipe and each branch riser( the bottom of the riser, the upper and lower ends of the vertical ring pipe network riser).
5. A valve should be used in the branch pipe of the annular pipe network, the connecting pipe running through the branch pipe network.
6. A valve should be installed in the starting end of the water distribution pipe from the indoor water supply pipeline to the households, public toilets, etc; valve should be used in the water distribution points of the water distribution branch pipe when there are 3 or more water distribution points;
7. Valve should be installed in the outlet pipe of the water pump, and the suction pump of the self priming water pump;
8. Valve should be used in the inlet, outlet and drain pipes of the water tank;
9. Valve should be installed in inlet pipe, water supply pipe of equipment (such as heaters, cooling towers,etc);
10. Valves should be installed in water distribution pipes for sanitary appliances(such as toilets, urinals, washbasins, showers,etc);
11. Valves should be installed in the front of some accessories, such as automatic exhaust valve, pressure relief valve, water hammer eliminator, pressure gauge, sprinkler hydrant,etc; and valves are used in the front and rear of pressure reducing valve and back flow preventer;
12. A drain valve should be installed at the lowest bottom of the water supply network;