Overview of Pressure Reducing Valves.
What is a Pressure Reducing Valve (PRV)?
A Pressure Reducing Valve (PRV) is a device used to regulate and maintain the pressure in a system at a stable level, lower than the inlet pressure. PRVs work by reducing the pressure from a high-pressure supply to a pressure level that meets the system's requirements, helping to prevent overpressure and protect other equipment from damage. Pressure reducing valves are widely used in water, steam, gas and oil supply systems, both industrial and domestic.

The importance of pressure reducing valves in industrial and domestic applications.

Pressure reducing valves (PRVs) play an important role in both industrial and domestic applications, with the following main benefits:

Protection of systems and equipment:
PRVs help maintain stable pressure and prevent overpressure in the system, protecting equipment such as pumps, pipes, and other valves from damage due to high pressure.

Improved performance:
By maintaining a constant and optimal pressure level, pressure reducing valves improve system performance, especially in industrial processes that require tight pressure control.

Energy savings:
PRVs help regulate pressure to avoid wasting energy by using unnecessary high pressure. This contributes to reducing operating costs in industry and saving water, gas, or electricity in residential applications.

Safety for people and the environment:
In industries such as oil and gas, chemicals, and manufacturing, pressure control is important to avoid leaks or incidents that could endanger workers and the environment. Pressure reducing valves help prevent pressure-related accidents.

Optimizing residential operations:
In domestic water and gas systems, PRVs help regulate water and gas pressure to appropriate levels, avoiding damage to appliances such as water heaters, showers, and plumbing systems.

In summary, pressure reducing valves not only ensure stable and efficient operation of the system but also play an important role in maintaining safety and protecting assets in both industrial and civil applications.

Overview of how pressure reducing valves help maintain system safety and efficiency.

Pressure reducing valves (PRVs) are an important device that helps maintain system safety and efficiency by controlling and regulating flow pressure in industrial and civil systems. An overview of how PRVs work to ensure these factors includes:

Pressure control to prevent overpressure:
PRVs automatically reduce the inlet pressure to a lower pressure level, suitable for the system requirements. This helps prevent overpressure, protecting the system from the risk of damage or pipe rupture, especially in water, gas, or oil supply systems.

Protecting equipment and systems:
When pressure exceeds the allowable limit, PRVs release or regulate pressure to ensure equipment and systems operate within safe limits. This minimizes the risk of damage to critical components such as pumps, valves, tanks, or pipes.

Maintaining stable performance:
PRVs help maintain stable pressure, consistent with the requirements of the operating process. By keeping pressure at an optimal level, PRVs increase system efficiency, reduce energy consumption, and optimize the flow of liquids or gases.

Promoting system longevity:
By preventing overpressure and minimizing pressure fluctuations, PRVs help extend the life of equipment, reducing the need for frequent repairs and maintenance.

Ensuring operator and environmental safety:
In many industries such as chemical, oil and gas, and electric power, PRVs play an important role in preventing high-pressure accidents, protecting operators and reducing the risk of incidents affecting the environment.

Reducing operating costs:
PRVs help regulate pressure to prevent the waste of energy and raw materials. This contributes to reducing operating costs, while optimizing production and distribution efficiency.

In short, pressure reducing valves help maintain system safety and efficiency by controlling pressure continuously and stably, protecting equipment and systems, and ensuring a safe operating environment.

How a pressure reducing valve works
Describe the basic operating principle of a pressure reducing valve.

The basic operating principle of a pressure reducing valve (PRV) is based on automatically adjusting the pressure of the flow to ensure that the system is always maintained at a safe and stable pressure level. Specifically, the operation process of the pressure reducing valve includes the following main steps:

High inlet pressure: The liquid or gas stream from a high pressure source enters the pressure reducing valve through the inlet.

Pressure detection: Inside the valve there is a pressure detection mechanism, usually a spring and a diaphragm or piston. When the inlet pressure exceeds the specified level, the spring will be compressed by the flow pressure, creating a reaction force to control the pressure reduction process.

Pressure adjustment: When the inlet pressure is too high, the mechanism inside the valve will open a door to reduce the pressure. The adjustment spring will move the diaphragm or piston to open or close the valve, depending on the inlet pressure

Minh họa hoặc sơ đồ về cơ chế điều khiển dòng chảy (tuỳ chọn).

 

Types of Pressure Reducing Valves
Direct Pressure Reducing Valve:
Simple structure, suitable for small systems with low flow.

Direct pressure reducing valve is a type of valve that automatically adjusts pressure based on the inlet pressure without the need for additional external control devices. When the inlet pressure is higher than the required level, the valve will reduce the outlet pressure by adjusting the flow through the valve. Here is a description of how the direct pressure reducing valve works:

Operating principle: The direct pressure reducing valve works by means of a diaphragm and spring mechanism. The spring will create a pushing force on the diaphragm, while the inlet pressure acts on the other side of the diaphragm. When the inlet pressure is greater than the compression force of the spring, the diaphragm will move and partially close the valve to limit the flow, reducing the output pressure.

Pressure adjustment: The operator can adjust the adjusting screw to change the compression of the spring. When the screw is tightened, the compression force of the spring will be greater, leading to increased output pressure. When the screw is unscrewed, the spring compression force is reduced, resulting in a decrease in the output pressure.

Application: Direct pressure reducing valves are often used in systems that require quick and uncomplicated pressure adjustment, such as in water supply systems, steam systems, and other industrial systems.

This type of valve is efficient and simple in design, suitable for many applications in both civil and industrial applications.

Typical applications of direct pressure reducing valves: often used for civil water systems.

Pilot-controlled pressure reducing valves:
More complex in structure, used for large systems with high flow rates.

Pilot-controlled pressure reducing valves are a type of pressure reducing valve that uses a remote control mechanism to adjust the output pressure. This valve is often used in systems that require more precise and stable control of pressure. Here is a detailed description of the pilot-controlled pressure reducing valve:

Operating principle
Structure: The pilot-controlled pressure reducing valve consists of a main valve and a pilot valve. The pilot valve acts as a control device to control the pressure in the main valve.

Operating:

Pilot valve: The pilot valve receives pressure from the outlet of the main valve. When the outlet pressure is higher than the required level, the pilot valve will open, allowing this pressure to return to a safer level.

Main valve control: The change in pressure on the pilot valve will affect the main valve, resulting in flow regulation and reduced output pressure.

Feedback: If the output pressure drops below the set level, the pilot valve will close, preventing further pressure reduction, maintaining stable pressure.

Advantages
Precise control: The pilot-controlled pressure reducing valve provides more precise pressure regulation than a direct pressure reducing valve.

Stability: This valve is capable of maintaining a stable pressure under changing load and flow conditions.

Large flow handling capacity: The pilot valve can control the main valve to handle large flows without being limited by the size of the main valve.

Applications
Water supply systems: Used in water supply systems to regulate and maintain water pressure.

Chemical industry: Used in applications that require precise pressure control during chemical production.

Thermal power: Often used in steam systems to control steam pressure.

Pilot-operated pressure reducing valves are often selected for applications that require high pressure accuracy and stability, while helping to optimize system performance.

Pilot pressure reducing valve applications: often used in industrial systems such as steam, gas, or oil pipelines.

Comparison between direct pressure reducing valves and pilot-operated pressure reducing valves (advantages, disadvantages, and applications).
Below is a comparison table between direct acting pressure reducing valves and pilot operated pressure reducing valves, including the advantages, disadvantages and applications of each type of valve.

 

Criteria Direct Pressure Reducing Valve Pilot Controlled Pressure Reducing Valve
Operating principle Direct operation based on inlet pressure and spring pressure. Using a pilot valve to control the main valve, allowing for more precise adjustment.

Advantages - Simple design, easy to install and maintain.

Suitable for applications with stable pressure and flow.

Lower cost. - Precise and stable control of outlet pressure.

Capable of handling larger flow rates.

Respond quickly to load changes.

Disadvantages - Inaccurate pressure adjustment.

Vulnerable to flow rate changes.

Not suitable for systems requiring continuously changing pressure. - More complex design, requiring many components.

Higher cost due to complex structure.
Applications - Simple applications such as water supply systems and compressed air systems.

Suitable for systems that do not require high pressure control. - Industrial systems requiring high precision, such as in the chemical and thermal power industries.
- Systems that need to maintain stable pressure under changing load conditions.

 

 

 

 

Conclusion

Direct Actuated Pressure Reducing Valves are suitable for simple applications where precise pressure control is not required. They are a good choice for systems with stable conditions and limited cost.

Pilot Actuated Pressure Reducing Valves are recommended for complex industrial applications where precise and stable pressure control is required, especially when operating conditions change. Although they are more expensive and more complex, the benefits in pressure control will be more effective in the long run.

 

Applications of Pressure Reducing Valves

Industrial Applications:
Used in steam, gas, oil and chemical processes to control pressure.

Pressure Reducing Valves (PRVs) are widely used in many industries due to their ability to control and maintain stable pressure in the system. Here are some of the main applications in industry:

Oil and Gas Industry
In the oil and gas industry, pressure reducing valves help maintain stable pressure in oil and gas pipelines, preventing sudden increases in pressure that can be dangerous. This helps protect equipment and ensure worker safety.

Chemical Industry
Chemical production and processing systems require stable pressure to ensure that chemical reactions take place properly. Pressure reducing valves help control pressure in tanks, pipelines, and production equipment, minimizing the risk of damage or accidents.

Food and Beverage Industry
In the food and beverage industry, pressure reducing valves help control steam and gas pressure during pasteurization, filling, and packaging processes. This ensures product quality and protects machinery and equipment from damage due to excessive pressure.

Energy and Power Industry
Pressure reducing valves are used in power plants to control pressure in steam and gas systems. Maintaining a stable pressure helps optimize the performance of turbines and generators, and prevents technical failures due to high pressure.

Water Industry
In industrial water supply systems, pressure reducing valves ensure stable water pressure at the point of consumption, avoiding pipe bursts or system failures due to excessive water pressure. They are commonly used in water pumping stations and urban water distribution systems.

Pulp and Paper Industry
In paper mills, steam is an important element in the production process. Pressure reducing valves are used to control steam pressure, helping to ensure that the papermaking process runs smoothly and efficiently.

HVAC (Heating, Ventilation, and Air Conditioning) Industry
Pressure reducing valves are used in HVAC systems to regulate the pressure of air and water in heating and cooling systems. This helps to improve energy efficiency and prolong the life of the system.

Pharmaceutical Industry
In pharmaceutical manufacturing, maintaining stable pressure is essential to ensure product quality and safety. Pressure reducing valves help control pressure during drug processing, cooking, and packaging.

Conclusion:
Pressure reducing valves are an important and indispensable device in industrial systems, playing an important role in maintaining safety, efficiency, and protecting equipment and people from potential risks due to excessive pressure.

The importance of pressure reducing valves in preventing system overload and protecting equipment.
Pressure relief valves play a vital role in preventing system overloads and protecting equipment from damage due to excessive pressure. Here are the main benefits that pressure relief valves provide in protecting systems and equipment:

Prevents overpressure incidents
Overpressure in a system can lead to pipe ruptures, equipment damage, and even endanger operators. Pressure relief valves reduce inlet pressure to the desired outlet pressure, ensuring that the system operates at a safe pressure, preventing serious incidents due to overloads.
Protect equipment and extend service life
Equipment such as pumps, boilers, tanks, and pipelines can be damaged if operated under unstable or excessively high pressure. Using pressure relief valves helps protect these devices from incidents due to sudden pressure increases, thereby extending the life of the equipment and reducing maintenance costs.
Maintain system performance
Pressure reducing valves ensure that the pressure in the system is always stable, helping the system operate more efficiently and smoothly. This is especially important in industries that require precise pressure control such as chemicals, food, pharmaceuticals and energy.
Reduce operating and maintenance costs
When the pressure in the system is well controlled by a pressure reducing valve, the equipment is less likely to encounter problems with damage or need to be replaced. This helps reduce maintenance costs and avoid unwanted incidents that lead to production stoppages, helping to optimize operating costs.
Enhance safety for the system and people
High pressure can cause dangerous situations for the system as well as for the operating people. Pressure reducing valves are important safety devices that help maintain the pressure at a stable level, thereby minimizing the risk of work accidents due to pipe rupture or equipment damage due to pressure overload.
Widely used in various systems
Pressure reducing valves are not only used in large industrial systems but also widely used in civil systems such as domestic water supply systems, heating and air conditioning (HVAC) systems. Ensuring stable pressure in these systems helps prevent equipment damage and save energy.
Conclusion:
Pressure reducing valves play a key role in protecting systems and equipment from problems caused by pressure

 

Installation and Maintenance Instructions
Instructions for proper installation to ensure optimal valve performance.
The importance of regular maintenance, inspection, and cleaning.
Troubleshooting tips for common problems such as water hammer, leaks, or unstable pressure.
Installation and Maintenance Instructions for Pressure Reducing Valves
Installation and maintenance of pressure reducing valves play an important role in ensuring stable and safe operation of water or compressed air systems. Here are the basic steps for installing and maintaining pressure reducing valves:

Installation Instructions for Pressure Reducing Valves
Step 1: Select the installation location
Choose an installation location near a water or gas source to easily adjust the pressure before entering other systems.
The installation location should be easily accessible for convenient maintenance and periodic inspection.
Avoid installing valves in places with excessively high temperatures or affected by adverse environments (dust, corrosion).
Step 2: Prepare tools and materials
Basic tools include: wrench, screwdriver, anti-leak tape, pressure gauge (if needed).
Check the pipes and fittings to ensure there are no leaks or deposits.
Step 3: Install the pressure reducing valve
Turn off the water or gas supply to ensure safety.
Install the valve with the arrow on the valve body pointing in the correct direction of flow.
Use anti-leak tape for threaded connections to prevent water or gas leakage.
Tighten the connections with a wrench, making sure there is no looseness.
Step 4: Adjust the pressure
After installation, turn on the water or gas supply and test the valve.
Use the adjusting screw on the valve to set the desired outlet pressure. Turn clockwise to increase pressure and counterclockwise to decrease pressure.
Use a pressure gauge to monitor the adjusted pressure level.
Step 5: Final Check
Ensure that there are no leaks at the connections.
Check that the system is operating properly and that the pressure is maintained at the desired level.
Pressure Relief Valve Maintenance Guide
Regular maintenance is necessary to maintain the performance of the pressure relief valve and avoid system failures.

Step 1: Regular Check
Monthly: Check the valve operation by measuring the inlet and outlet pressure to ensure that the valve is operating at its proper capacity.
Quarterly: Check the valve joints and body for leaks or potential problems.
Step 2: Clean the valve
For systems that contain a lot of impurities, dirt can accumulate in the valve. Remove the valve and clean the internal parts such as the diaphragm and valve seat to remove dirt.
Use clean water or a specialized cleaning solution to clean the parts.
Step 3: Check and replace worn parts
The diaphragm, spring, and adjusting screw are parts that are susceptible to wear after a period of use. If signs of cracking, wear, or loss of performance are detected, they should be replaced immediately.
For pilot-operated valves, check auxiliary valves such as the main and auxiliary control valves to ensure the smooth operation of the entire system.
Step 4: Check the specifications
Periodically recheck the outlet pressure to ensure that the valve maintains a stable pressure level. If a large difference between the inlet and outlet pressure is detected, the valve may need to be calibrated or replaced.
Step 5: Replace the valve when necessary
If the valve is severely damaged or cannot be maintained to restore its function, a new valve should be replaced to avoid causing major problems in the system.
Safety notes for installation and maintenance:
Always disconnect the power supply (water or gas) before performing any installation or maintenance work.
Wear protective equipment such as gloves and goggles when handling valves in high pressure systems.
Check the pressure carefully before and after adjustment to ensure stable system operation.
Proper installation and maintenance will help the pressure reducing valve operate stably, prolong the life of the equipment, and ensure the safety of the system and the user.

 

 

Top Pressure Reducing Valve Manufacturers
Popular pressure reducing valve brands in Vietnam: Yoshitake, TLV, VENN, ARI, Spirax Sarco, Fisher, Samyang, Yooyoun, etc.
Most of the products are available in Vietnam.