Valves are the key “switches” in water supply systems, controlling water flow, pressure and safety. Understanding core types such as gate valves, butterfly valves, ball valves and their selection points is the basis for ensuring efficient and stable operation of the pipe network. This guide provides you with the necessary knowledge!
Valve – The “Traffic commander” of the water supply system
The core role of valves in water supply systems
Valves are key control devices in water supply systems. Their core functions are to accurately open and close water flows, regulate flow rates, isolate pipe networks for maintenance and overhaul, and prevent backflow to protect equipment. They are the basic components that ensure the safe, reliable and efficient operation of the entire water supply system.
Why Knowing Valve Types Is Important
There are many types of valves in the water supply system (such as gate valves, butterfly valves, ball valves, etc.), each with its own application scenarios. Understanding the different types is the prerequisite for correct valve selection. Improper selection will lead to low efficiency, increased energy consumption, maintenance difficulties, and even safety risks such as pipe bursts and water hammers, which directly affect system efficiency, operating costs, and service life.
Main types of valves in water supply systems and their applications
Cancello Valvola
: reliable isolation guard
The gate valve is opened and closed by lifting the gate plate perpendicular to the water flow. It has a simple structure, small flow resistance, good sealing, and almost no obstruction to the water flow when fully opened. It is an ideal choice for the main isolation valve of the main line of the water supply system and is suitable for occasions that require complete shut-off and infrequent operation.
Butterfly Valve: a cost-effective flow controller
The butterfly valve uses a disc (disc) to rotate in the pipe to control the water flow. It has a compact structure, light weight, fast opening and closing, and low cost, and is particularly suitable for large-diameter pipes. It is often used in flow regulation and occasions that require fast opening and closing, such as pump station outlets and pipe network branch points.
Palla Valvola
: a reliable choice for fast opening and closing
The core of the ball valve is a sphere with a channel, which can be turned on and off by rotating 90 degrees. It has extremely fast operation (quarter turn), excellent sealing, minimal flow resistance and high reliability. In the water supply system, it is mainly used for branch pipes, equipment inlets and parts that require frequent operation that require quick and reliable cutting.
Check Valve: the guardian of one-way flow
Check valves (such as swing, lift, and wafer) only allow water to flow in one direction and automatically prevent backflow. They are installed at the outlet of the pump to prevent water from backflowing and impacting the impeller (water hammer) when the pump is shut down. They are also used in pipe networks to prevent backflow pollution in different pressure ranges, and are the key to ensuring system safety.
Pressure reducing Valve: regulator for stable water pressure
The pressure reducing valve can automatically reduce the higher upstream pressure and stabilize it at the set downstream pressure. It protects downstream pipelines and equipment (such as household water devices and instruments) from high pressure damage and ensures stable and comfortable water pressure at the user end. It is often used for high-pressure pipe network access to low-pressure areas, high-rise building zoning water supply and household pipelines.
Exhaust Valve: the invisible hero that removes air
The exhaust valve (automatic or compound) automatically exhausts the accumulated air at the high point of the pipeline to prevent “air blockage” from hindering the water flow, increasing energy consumption and even causing cavitation damage. It ensures the water delivery efficiency of the system and is an indispensable safety accessory for the high point of the pipeline network and the pump station.
Drain Valve/Sewage Valve: the guarantor of system cleanliness
The drain valve (usually ball or gate type) is installed at the lowest point of the pipeline or where it needs to be emptied. It is used to regularly discharge deposited impurities (sand, rust) or empty the pipe section for maintenance and flushing to keep the water clean and the pipeline unobstructed. (Keywords: drain valve, drain valve, pipeline emptying, system flushing)
Other special Valves
- Control valve: Designed for precise control of flow or pressure, fine adjustment is achieved through a special valve core and is used at process points that require stable flow or pressure.
- Safety valve/pressure relief valve: It automatically opens to release pressure when the system pressure exceeds the standard accidentally. It is the last line of defense to protect pipelines and equipment from damage caused by overpressure.
- Fire hydrant valve: Specially used in fire hydrant systems to control the flow of fire water, usually need to meet specific fire regulations requirements (such as operation method, pressure bearing capacity).
How to choose the right Valve for your water supply system?
Choosing the right valve for your water supply system is critical because it directly affects the efficiency, safety, and life of the system. Here are five key valve selection considerations:
Clarify functional requirements
First, determine the core function that the valve needs to undertake: is it used for complete isolation (select gate valve, ball valve), flow/pressure regulation (select butterfly valve, regulating valve, pressure reducing valve), backflow prevention (select check valve), automatic exhaust (select exhaust valve) or discharge impurities/empty (select sewage valve)? Function is the primary basis for selection.
Matching working condition parameters
The valve must be precisely matched to the pipe size (DN/inch) and be able to withstand the maximum working pressure and temperature of the system (select the correct pressure rating, such as PN10, PN16, Class150). Mismatched operating parameters are the main cause of valve failure and leakage.
Consider fluid properties
The valve material must be compatible with the fluid being transported. Cast iron, ductile iron, bronze or stainless steel are commonly used to transport clean water; higher-grade corrosion-resistant valves (such as all-stainless steel, rubber-lined/plastic-lined valves) are required to transport sewage or corrosive media. The selection of internal material (valve seat, valve plate/ball) is also critical.
Evaluate Operation and Maintenance
Consider the frequency and method of operation: Is manual operation convenient? Do you need electric or pneumatic actuators for remote or automatic control? Is the installation space limited (e.g., butterfly valves or ball valves are preferred in compact spaces)? Is the valve design convenient for daily inspection, lubrication and repair (maintenance convenience)?
Weighing the costs and benefits
Valve selection requires a balance between initial purchase cost and life cycle cost. Consider long-term energy consumption (such as energy saving with low flow resistance valves), maintenance frequency and cost, expected service life, and potential risks caused by improper selection (such as leakage, water hammer damage, system downtime losses). Sometimes high-quality valves with higher initial investment are more cost-effective in the long run.
Key points for installation and maintenance of valves in water supply system
Correct installation and regular maintenance are the key to ensure the long-term reliable operation of water supply system valves, their expected functions and extended service life. The following are 4 key points:
Follow installation specifications
Install strictly according to the design drawings and manufacturer’s instructions: ensure the direction is correct (especially check valves and pressure reducing valves have flow direction requirements); pipelines must be clean and aligned to avoid stress caused by strong assembly; large-diameter valves must be independently supported; flange connections must be evenly tightened with bolts; consider future operation and maintenance space.
Implement a regular inspection and maintenance program
Establish and implement a regular valve maintenance plan: including checking external leakage, valve stem/actuator condition, lubrication points (fill with qualified grease as needed), whether the valve opens and closes smoothly, and whether the exhaust valve/drain valve is working properly. Record the inspection results and form a maintenance file.
Identify and troubleshoot common faults
Valve leakage (packing, valve seat) and valve blocking (stem corrosion, foreign matter stuck) are the most common faults. Find out the cause in time (seal aging, impurities, improper operation, corrosion), and perform repairs (such as replacing packing, valve seat, removing foreign matter, lubrication) or replace damaged parts.
Implementing life extension strategies
The key to extending valve life lies in preventive maintenance: operate the valve regularly (to prevent long-term sticking); keep the valve stem clean and lubricated; strengthen protection in corrosive environments or use corrosion-resistant materials; regularly operate the exhaust valve/drain valve to exhaust air and impurities; and avoid the valve being subjected to pressure or temperature shocks beyond the design range.
Choose the right valve to ensure efficient and stable operation of the water supply system
Valves are the core of water supply system control. Scientific selection (accurate matching of functions, working conditions, and fluids) combined with standardized installation and continuous maintenance (inspection, lubrication, and drainage) are the basis for optimizing water supply system efficiency, ensuring system stability, preventing water hammer and leakage, extending valve service life, and ensuring water supply safety. In the face of complex needs, consulting valve experts can avoid risks and achieve the best cost-effectiveness. Take action now, select the right valve for your system and implement professional maintenance to lay the foundation for efficient and stable operation!
FAQ
Q1: What is the most commonly used valve in water supply systems?
A1: Gate valves and butterfly valves are the most commonly used types. Gate valves are often used for main isolation of trunk lines due to their reliable sealing and low flow resistance; butterfly valves are widely used for flow regulation and branch pipelines due to their economy, fast opening and closing, and suitability for large diameters.
Q2: What is the difference between butterfly valve and gate valve? Which one is better?
A2: The gate valve has very little flow resistance when fully open, and is suitable for full open/full closed isolation, but it is slow to open and close and has a large size; the butterfly valve has extremely fast opening and closing, compact structure, low cost, and is suitable for regulation and frequent operation, but has a certain flow resistance when fully open. “Better” depends on the application: select the gate valve if a tight seal is required for isolation; select the butterfly valve if regulation or fast opening and closing is required.
Q3: Why do I need to install a pressure reducing valve?
A3: The pressure reducing valve is a key device to prevent excessive water pressure. It can automatically reduce the upstream high pressure to the set safe downstream pressure, protect the user-side appliances (water heaters, faucets) and pipes from high pressure damage, avoid water leakage and noise, and ensure comfortable water use (especially in high-rise buildings).
Q4: Does the exhaust valve require regular maintenance?
A4: Yes! Although the automatic exhaust valve can automatically exhaust, it is still necessary to check regularly (monthly or quarterly) whether it is blocked and whether it can float and close normally. The large-diameter exhaust port of the composite exhaust valve needs to be tested manually (according to the operating instructions). Neglecting maintenance will lead to exhaust failure, causing air blockage, insufficient flow and even cavitation damage.
Q5: How to determine whether the valve needs to be replaced?
A5: The following signs indicate that the valve may need to be replaced: severe external leakage (packing or valve body cannot be repaired); internal leakage (flow continues after closing, affecting the isolation effect); extremely difficult to operate or completely stuck (even if lubricated); severe corrosion or cracking of the valve body; or frequent repairs cannot restore normal function.
Q6: What are the advantages of smart valves in water supply systems?
A6: The core advantages of smart valves (equipped with sensors and actuators) are: real-time remote monitoring of valve status (opening, pressure, leakage); precise remote/automatic control (adjusting flow and pressure on demand); predictive maintenance (analyzing data to predict failures); optimizing system efficiency (reducing leakage, balancing pressure), and improving management level and water supply safety.
Mastering the selection, application and maintenance of various valves (gate valves, butterfly valves, ball valves, check valves, pressure reducing valves, exhaust valves, and drain valves) in the water supply system is the key to ensuring efficient, stable and safe operation of the pipeline network. As a JH valve manufacturer with 60 years of rich experience, we strictly follow the ISO 9001 and API Q1 certification systems, relying on precision casting (CT7 grade) technology and rigorous testing to provide full-specification, high-performance valve solutions for water systems (municipal water supply, water treatment, pipeline networks, and buildings). Its TA-Luft A-level excellent sealing significantly reduces water resource leakage, and the optimized structure and corrosion-resistant materials (ductile iron/stainless steel/bronze) ensure an ultra-long service life (millions of opening and closing verification), and support electric/pneumatic drive (ISO 5211) and intelligent upgrades (IoT monitoring, Modbus/Profibus communication) to achieve smart water management; contact the JH technical team immediately to obtain free selection guidance and 1-on-1 working condition analysis, and let JH become your reliable partner for improving water supply efficiency and ensuring water quality safety with its excellent quality of “zero leakage and million times of life”!
