Preface
Water, the most important element in the existence of every living being, is also the key to the functioning of the complex processes of the contemporary economy. Water supply system is a complex and mostly concealed network that connects the source of water to our taps and factories. This complex infrastructure which is a creation of human beings guarantees the efficient and safe supply of this vital resource. In this network, water valves act as the necessary protectors. These are some of the most important but unnoticed parts that are responsible for regulating the flow, pressure and direction of water. They are crucial in the proper functioning of the water system, protection from contamination, pressure regulation, and supply of water to the consumers.
This extensive article is designed to shed light on the diverse nature of these indispensable devices, explore the different types of water valves, the key selection criteria that determine their performance, and the basic care procedures that are essential for the longevity of these devices and the continuous functioning of the water supply system. In this paper, we will try to understand the role of these mechanical sentinels in our lives and in the industrial world.
What Are Water Distribution Valves and Why Do They Matter?
A water valve is in essence a mechanical tool that is installed in a water supply system to regulate the flow of water. It is possible to consider them as the traffic signals and the guardians of the water system. Their main purpose is to control the flow, whether it is to increase or decrease the flow rate to accommodate the need or to channel it through the water supply lines to a certain area. Apart from switching on and off, valves are involved in several important functions. They can control the flow rates accurately, regulate the pressure in the required zones of the system, prevent the backflow of contaminated water, and even help in the discharge of trapped air or the elimination of sediment.
The importance of these valves cannot be overemphasized. Firstly, they are crucial in guaranteeing the availability of water supply. In the event that a part of the system needs to be fixed or has developed a fault, the valves enable the isolation of the affected area without affecting the rest of the network or supply. This capability reduces inconvenience and ensures that core services are provided. Secondly, valves are used in the management of water resources in order to ensure that they are used efficiently. These devices assist in controlling the flow and pressure of water hence reducing wastage through leakage or poor distribution of the scarce resource.
In addition, water valves are very useful in ensuring safety of the system. They can stop backflow, thus protecting the potable water from being contaminated or can protect the system from high pressure water. From an operational perspective, control valves can help to minimize the energy used by pumping stations by delivering water at the necessary pressure and flow rate, without the need for additional pumping power. The durability of the entire plumbing system is also directly connected with these valves. Proper selection and consistent maintenance also go a long way in increasing the life span of the pipelines and other equipment by reducing stress and wear.
Valve Types in Water Distribution Systems
Valves are an essential component of a water distribution system and are designed to perform various functions with varying levels of effectiveness and appropriateness. It is important for system designers, operators, and maintenance personnel to understand the differences between each valve.
Gate Valves
These are mainly on/off types of valves that operate by the linear motion of a gate or a wedge across the flow. When fully open, the gate is out of the flow stream and does not obstruct the flow at all, thus creating very low pressure drop which is desirable in long pipelines. Gate valves are not intended for throttling or flow control; if used in this way, the gate and seats will experience increased wear and vibration. They are most suitable for applications requiring infrequent shut-off, such as isolating sections of the network for maintenance or repair. There are many basic types of valve designs: the rising stem and non-rising stem designs and so on, and every of them has its benefits in terms of the visibility of the valve position and the space available for the valve’s installation. They are relatively simple and inexpensive and are therefore widely used for mainline isolation.
Butterfly Valves
These valves have a disc that rotates on a central shaft within the body of the valve. In the closed position, the disc is perpendicular to the flow, obstructing it and in the open position, the disc is rotated 90 degrees so that it does not interfere with the flow. Butterfly valves are relatively small in size, light in weight and are not very expensive, particularly in large sizes. They have good flow control characteristics and can be used for on/off services as well as throttling services. Although they are very effective, their sealing may not be as good as some other water valve types especially at high pressures and the disc is always in the flow path thus there is always some pressure drop even when fully open. They are used extensively in water treatment industries for controlling the flow through different processes and in water supply systems for general flow control and isolation.
Ball Valves
Ball valves use a spherical ball with a hole through its center, and when the ball is rotated 90 degrees, the flow path is closed tightly. When the bore is parallel to the pipeline, the valve is fully open and does not restrict the flow of the fluid. Ball valves are rotary valves that operate on the quarter turn basis and are ideal for on-off applications due to their tight shut off. Although they can be used for throttling, when used for a long time in a partially open position, the valve seats will wear out. Due to their small size, non-complex structure and low maintenance, they are widely used in small diameter pipelines, service connections and other industrial applications in residential plumbing.
Check Valves
Also referred to as non-return valves, these important devices are intended to close automatically to prevent the backflow of hot water or cold water. They work without any active control and are activated by the water pressure of the fluid only. When the pressure on the inlet side is higher than on the outlet side, the valve opens and flow is in the intended direction and not in the opposite direction. If the pressure increases or decreases to a certain level, the valve shuts to avoid backflow. There are various types of check valves such as swing check, lift check, and ball check valves that are designed and suitable for different applications. They are mainly used to prevent pollution of water sources, protect pumps and other equipment from back pressure, and maintain the flow of water in one direction. They are usually fitted after pumps, at the outlet of storage tanks, and in any other place where backflow is likely to occur.
Globe Valves
These valves control the flow of water by means of a disc or plug that moves perpendicularly to the flow stream into or out of a seating ring. This design makes globe valves suitable for applications where precise control is critical since they offer good throttling capabilities. However, due to the complex flow path through the globe valve, the pressure drop is higher than that of gate or ball valves. They are commonly employed in applications where the valve is frequently opened and closed and where there is a need to control the flow of fluids to certain sections of the system or where there is a need to reduce pressure gradually. Although they provide better control, they are more complicated in design and have higher pressure drop and therefore are not ideal for simple on/off isolation in main pipelines.
Pressure Reducing Valves (PRVs)
These are specialized automatic valves that are used in regulating pressure in water systems that distribute water. Their main purpose is to decrease a higher inlet pressure to a lower, desired outlet pressure and to keep this pressure level relatively stable regardless of changes in the upstream pressure or downstream flow rate. PRVs are particularly important in areas where there are steep gradients, in supplying water to tall structures and in safeguarding other pipelines and fixtures from high pressure downstream. They are of diaphragm or piston type that control the valve opening depending on the downstream pressure. PRVs also assist in avoiding leakage, controlling water hammer and increasing the durability of the distribution system by regulating the pressure of water.
Air Release Valves
Air in water lines can cause many problems such as restricted flow, poor pumping, and water hammer which is damaging to the system. These are valves that are used to release trapped air in the system automatically. These are usually fitted at the top of the pipeline where air is trapped and they enable air to be released while preventing water from escaping. There are different types of valves for this purpose; there are small orifice valves for constant release of small volumes of air and large orifice valves for releasing large volumes of air that may build up during the filling process or any other transient condition. These valves help in enhancing hydraulic performance and avoiding operational problems through the elimination of air from the system.
Sediment Drain Valves
Eventually, sediment, sand, and other particles may settle at the bottom of water supply pipes. This accumulation can decrease the diameter of the pipes, which in turn affects the flow rate and may also affect the quality of water. Sediment drain valves are usually placed at the bottom of the pipeline system where sedimentation of the heavier particles is likely to occur and enable the periodic cleaning of this material. These are normally operated by hand and are opened to let out the water containing sediments. Periodic opening of sediment drain valves is crucial in the proper functioning of the water supply system and provision of clean water to the consumers.
How to Choose the Right Water Distribution Valves for Your Systems?
The choice of the valve for a particular application in a water system depends on several factors as explained below. To make it easier to understand and to give more detailed information, let’s divide the main points to focus on:
Fluid Characteristics: The specific fluid dictates valve selection. Although treated water is used for drinking, different chlorine concentrations affect the selection of materials. Raw water with solids entails designs that are not easily prone to clogging. Wastewater necessitates corrosion-resistant materials. Treating chemicals requires chemical compatibility. Hence, it is crucial to determine the exact type of fluid to be used in order to choose the right type of water valve.
Flow Requirements: The amount of water that needs to flow through the valve is another important factor that must be determined to ensure the right size and water line is chosen. The water demand of the system may vary and the selected valve should be able to operate at the full range of flow rates without compromising on the pressure drop or cavitation.
Pressure Rating: This includes the working conditions of the system and the ability of the valve to handle these pressures. The valve must be able to withstand at least the maximum pressure that is expected to be exerted on it during operation and it is advisable to consider the surge pressures such as water hammer by choosing a valve that has a safety margin. Also, some of the valves, especially the pressure relief valves, may require a certain minimum pressure to function effectively.
Functional Needs: The specific role that the valve is required to play in the system will help in the elimination of the various types of water valves. This can be basic on/off for isolation where gate, ball or butterfly valves are normally appropriate. For throttling purposes, globe valves or some specific types of butterfly or ball valves are generally employed for the purpose. Check valves are used for backflow prevention while pressure reduction needs pressure relief valves. Last but not the least, there are some other valves such as air release valves and sediment drain valves which are used for certain operational requirements concerning the quality of the fluid and the performance of the system.
Installation Space: The nature of the installation space can also determine the type of valve to be used. Limited space may necessitate selecting a smaller design and this may require one to choose a smaller type of valve like the butterfly or ball valve instead of the gate or globe valve. Moreover, the existing supply line will determine the type of connection that is applicable to the valve, whether flanged, threaded, welded or grooved and therefore compatibility is crucial in this case.
Valve Material: The material of construction for the valve body and internal components is important to consider in order to determine compatibility with the fluid and the operating conditions.
| Material | Key Features | Suitable For (Applications) |
| Ductile Iron | Low cost, good strength, impact resistance | General water supply, wastewater, low-medium pressure, cost-sensitive applications |
| Carbon Steel | High strength, high pressure/temperature | High pressure/temperature fluids, steam, oil & gas (requires corrosion protection) |
| Stainless Steel | Excellent corrosion resistance, hygienic | Potable water, food & beverage, pharmaceuticals, chemicals, seawater, high hygiene needs |
| Plastics | Lightweight, corrosion resistant, low cost | Low pressure/temperature fluids, chemicals, water treatment, irrigation |
| Alloy Steel | Superior corrosion/heat resistance, high strength | Extreme conditions (high temp/pressure, strong corrosion), specific chemical/power industries |
| Bronze/Brass | Good corrosion resistance, easy to machine | Residential plumbing, hot water systems, low-pressure water, instrument valves |
| Cast Iron | Low cost, good wear resistance, brittle | Low-pressure water supply/drainage, large valves |
| Ceramics | High wear/corrosion/heat resistance | Special media, high abrasion/corrosion environments, high-temperature flue gas |
Cost: This is the total cost of the product, including the price of the product, installation costs, and the costs of maintaining the product in the long run. Valves are available in different types and materials, and the cost of the initial investment depends on the type of valve and the design of the valve that is to be installed. This is because long-term maintenance costs depend on the frequency and the level of complexity of the maintenance that is required.
Operation Method: The way in which the valve is opened and closed depends on the application and the degree of automation needed. Lever or handwheel operation is appropriate for occasional use only. However, electric actuators offer the benefits of remote control and automation, accurate positioning and low energy consumption, which makes them suitable for use in automated control systems. Pneumatic actuators are those that are operated by compressed air and are more responsive than hydraulic ones and are used where quick response is needed or where the environment is hazardous. Vincer offers a series of electric and pneumatic actuated ball, butterfly, gate, globe and other types of valves and so on, which can meet the economical and efficient requirements of different industries.
Why Choose Vincer for Your Water Distribution Valves Needs?
In the case of water system distribution which is a critical infrastructure, it is important to choose a valve manufacturer that is reliable. Vincer sets itself apart as a reliable supplier of electric and pneumatic actuated valves, as well as ball, butterfly, gate, and globe valves, industrial manual valves, and control valves. This is further supported by our ISO 9001:2015 certification which covers quality management from purchasing to delivery. In addition, CE certification proves that our products meet the European safety standards, and FDA certification proves that our products meet high safety and quality standards especially for industries that require high hygiene standards. Vincer’s RoHS certification also proves our commitment to environmental protection as it ensures that our products do not contain any hazardous substances. In choosing Vincer, you get a partner who will offer you certified and quality valves and who will ensure that you get the technical support you need in the water distribution industry.
How to Properly Maintain and Extend the Life of Water Distribution Valves
Regular Inspection
It is also important to set up a schedule for inspection so that problems can be detected early before they become major. In these inspections, visually check the valve body, the actuator if any, and all joints for signs of leakage, rust or any physical damage such as crack or dent. Any unusual noise or vibration that is felt or heard during the operation of the valve should be considered as a sign of internal wear or malfunction. It is also necessary to look around for any signs of water leakage, which may be a sign of a slow leakage. Recording the findings of each inspection such as the date, observations and actions taken will help in tracking the status of the valves over time and create a record of the maintenance history hence enabling early intervention before major breakdowns occur.
Lubrication
Most water valves have internal components that include stems, gears, and bearings that need to be lubricated to reduce friction and wear. Wear between the moving parts results in high operating torque, valve sticking or stiff to open or close and eventually fail. The type of lubricant to be used should be determined by the manufacturer’s recommendation and should be applied at the recommended intervals to enhance the efficiency of the valve. It is important to note that the type of valve and the environment in which it will be used may call for different types of lubricants and therefore the manufacturer’s recommendations should be sought. Lubrication also prevents wear and tear and also prevents seizing of moving parts hence increasing the life span of the valve.
Cleaning and Corrosion Prevention
The outer surface of water valves is exposed to various elements and therefore it may accumulate dust, dirt and other materials that may lead to corrosion and also make it difficult to conduct visual assessment. Cleaning the valve body and its parts on a regular basis is important to ensure that the valve is not compromised and to easily detect any signs of leakage or rusting. In areas where valves are subjected to moisture or corrosive substances, it is advisable to paint or coat the valves as advised by the manufacturer to avoid rusting of the material. It is important to control corrosion at its initial stage because it affects the structure of the valve and may require replacement.
Correct Use and Operation
The proper functioning of water valves as per their design and the purpose for which they are intended is crucial to avoid damages and to increase their durability. Do not use force when operating manual valves because this may cause damage to the internal parts of the valve. For actuated valves, check that the control signals are within the range and the power supply is good. Some of the problems that may occur due to improper operation include water hammer, which is likely to cause damage to the valve and the pipeline surrounding it, for instance, when one tries to throttle with a gate valve or when one closes a large valve rapidly. It is crucial to train the personnel on the right usage of each type of water valve in the system to avoid shortening its lifespan or causing an accident.
Periodic Maintenance and Replacement of Wear Parts
Despite proper inspection and usage, some parts of the water valves like the seals, gaskets, and packing are bound to degrade over time due to the effects of water and mechanical pressure. It is important to adhere to the maintenance schedule provided by the valve manufacturer to determine when these parts should be checked and possibly replaced. It is important to replace the worn or damaged parts of the valve immediately to ensure that the sealing capability of the valve is not compromised by leakage. Failure to replace the wear parts will result in reduced efficiency, increased leakage, and ultimately valve failure. Therefore, it is recommended that the water distribution system should maintain a stock of the most frequently used wear parts and have a maintenance schedule to reduce the time that the system will take to be out of order.
Conclusion
Water distribution valves are essential parts of the system that provides this essential commodity to our homes and industries. This is because they are responsible for controlling, regulating and isolating water flow in these systems which are critical in terms of reliability, efficiency and safety. It is therefore important to understand the various types of valves available, the factors that are important in the selection of the valves and the proper maintenance practices that should be followed in the management of water distribution networks.