Share optimized solutions, professional valve knowledge and industry news

Please enter the relevant terms or keywords you need to consult, and relevant articles will appear in the search results. If you can’t find the answer you need, please feel free to contact us and we will be happy to help. Or you can directly send an email to [email protected]

3 Typical Systems of Steam Pressure Reducing Station

This post is explain 3 typical systems of steam pressure reducing station.
Table of Contents
    Add a header to begin generating the table of contents

    Through years of manufacturing control valves & self-operated regulators, with rich experience in field application and practice, analysis, and summary, we have analyzed and compared the three schemes of steam pressure reduction in the main pipeline of the factory, so as to select the appropriate solution to achieve the best decompression and stabilization effect. Due to the needs of the factory’s production process, steam is an indispensable process medium. Steam needs to be imported from the power plant. Because the distance between the power plant and the factory is relatively large, there are large pressure fluctuations, and the actual flow rate fluctuation range of the factory is large. The pressure of the main steam pipeline entering the factory is reduced and stabilized. To solve the above problems, the following 3 typical solutions are usually adopted.

    pressure regulators 1
    pressure regulators for steam prv station

    The first option is to use a steam self-operated pressure regulator, the second option is to use a pneumatic or electric globe type control valve to control the process parameters, and the third option is to use two pneumatic or electric globe types control valves in parallel for split-range control.

    Three Typical Solutions For Steam Pressure Reducing Station

    #1 Using a Steam Self-Operated Pressure Regulator

    Using a self-operated steam pressure regulator as a steam prv station is simple and convenient, with little maintenance costs, and is especially suitable for on-site situations where there is no electricity and no air power. Therefore, it has been widely used in steam pressure reduction systems, the following are the advantage of this solution.

    1 steam self operated pressure regulator
    steam self-operated pressure regulator
    1. The pressure setpoint can be adjusted on-site within the pressure adjustment range;
    2. The valve body and the actuator adopt modular design, and the actuator or spring can be changed according to the site requirements to realize the rapid replacement of the pressure adjustment range within a certain range;
    3. The self-operated steam pressure reducing valve generally uses bellows as the pressure balance element. The pressure change before and after the valve does not affect the force of the valve core, which greatly accelerates the response speed of the valve, thereby improving the adjustment accuracy of the valve;
    4. The structure of the cage balance valve adopts a self-balanced and double-sealing surface valve plug as a throttling part. The medium should be clean and free of particles. It is suitable for occasions where the pressure drop is large, the valve diameter is large, and the leakage rate is not high;
    5. The structure of the double-seat valve adopts a self-balanced & double-seal & double-seated valve plug as the throttling element, which is suitable for occasions with larger valve diameters;
    6. The diaphragm type actuator adopts the rubber diaphragm as the pressure detection element, which has low rigidity, high sensitivity, rapid response, and high adjustment accuracy, and is suitable for control pressure ≤ 0.6MPa;
    7. The piston-type actuator adopts the cylinder/piston as the pressure detection element, which is suitable for the application where the control setting value ≥ 0.6MPa pressure;
    8. The bellows actuator adopts bellows as the pressure detection element, which is suitable for high temperature and other severe working conditions.
    pressure regulators for natural gas tanking systems
    pressure regulators for natural gas tanking systems

    Special attention should be paid to the following key points in the scheme of adopting self-operated steam pressure regulator, which is also problems that often occur in improper use in practical applications:

    NO. AttentionsFunctionsProblems
    1A gas tank should be installed after the valveHas the function of buffering and stabilizingWhen the flow rate changes, a large pressure fluctuation phenomenon occurs
    2An overpressure protection device should be installed after the pressure reducing valvePrevent the downstream valve from being broken (I.e. safety valve), to prevent the self-operated pressure regulator from being damaged due to the pressure rise due to the close to zero flow after the valve.
    3The set pressure of the safety valve cannot be close to the working pressurePrevent frequent take-off of safety valveIf the flow rate is too small, the self-operated pressure regulator tends to close, and the safety valve takes off frequently.
    4To minimize the friction at the packing seal of the self-operated steam pressure regulatorPrevent the valve response lag due to excessive friction.Cause the upstream safety valve to jump frequently or the pressure is too low

    #2 Using a pneumatic or electric globe type control valve to control the process parameters. The characteristic is that the adjustment accuracy is much higher than that of the self-operated steam pressure regulator, but the price and maintenance costs are higher.

    2 use a pneumatic or electric globe type control valve to control the process parameters
    2 use a pneumatic or electric globe type control valve to control the process parameters
    1. Globe valve
    2. Pneumatic control valve (with positioner)
    3. Safety valve
    4. Pressure transmitter
    5. Console (process controller)
    motorized control valves right position
    motorized control valves right position

    Overview of Scheme 2: The pressure transmitter feedback 4-20ma.DC current signal according to the measured pressure, and compares it with the set value in the console. When the difference between the two reaches a certain value, the console sends an adjustment signal to the pneumatic control valve. According to this signal, the actuator of the pneumatic control valve causes the valve stem to drive the plug to produce displacement and change the flow through the control valve until the pressure at the test point meets the requirements. So as to achieve the purpose of automatically adjusting the pressure.

    The structure of the globe type control valve is basically top-guided single-seat, single-seat cage guided, double-seat, and low-noise trim according to process conditions.

    The above two schemes are the two commonly used solutions in factories, but in actual applications, the flow rate of downstream control valve changes greatly, especially when the steam consumption is very small, that is, the valve opening is small, and the valve is not very stable at low valve opening, and it will cause valve oscillation.

    Solution: In this case, it is recommended to use solution 3, which uses two pneumatic control valves in parallel.

    #3 Using two pneumatic or electric globe-type control valves in parallel for split-range control.

    When control valve A receives the signal 4~12.5mA, the valve opening responds from closed to fully open, and when control valve B receives the signal 11.5~20mA, the valve changes from closed to fully open. These two valves are realized by two positioners that lead to action. When the working flow capacity is small, the B valve is in the closed state, which is realized by the change of the opening of the A valve.

    actuated control valves2
    1/3 2/3 steam valve control
    actuated control valves3
    1/3 2/3 steam pressure reducing station
    actuated control valves1
    steam letdown station

    When the required flow rate is large, even control valve A is fully opened that still cannot meet the requirements, then control valve B will open to increase the flow capacity of steam. Adopting solution 3 can not only meet the load change requirements during production but also improve the control accuracy and stability.

    3use two pneumatic or electric globe type control valves in parallel for split range control
    Reducing pressure steam system (prv station for steam)
    1. Globe valve
    2. Control valve A (pneumatic control valve with positioner and air filter pressure reducer)
    3. Safety valve
    4. Pressure Transmitter
    5. Console (process controller)
    6. Control valve B (pneumatic control valve with positioner and air filter pressure reducer)
    Feature Comparison
    Valve Type
    CostPrecision & StabilitySuitable ApplicationApplication Examples
    Option 1
    (One self-operated Pressure Regulator)
    Cost-EffectiveLow-No power supply or air source
    -When the flow rate changes relatively little
    -The set pressure of the safety valve cannot be close to the working pressure
    Upstream Pressure: 8~10kg/cm2
    Downstream Pressure: 5 kg/cm2
    Flow Rate: 6~10t/h
    Selection Valve Size: DN100
    (Direct Response From the Pipeline)
    Option 2
    (A Pneumatic Control Valve)
    More ExpensiveGood -Have power supply or air source
    -Can be remotely set and displayed
    -Generally used in self-operated steam pressure regulator can not meet the requirements, especially when the flow rate changes relatively large and
    Where precise control is required
    Upstream Pressure: 8~12kg/cm2
    Downstream Pressure: 5 kg/cm2
    Flow Rate: 2~10t/h
    Requirement: Precise/accuracy control
    Select Valve Size: DN100
    (Input Signal: 4~20mA )
    Option 3
    (Using two pneumatic or electric globe type control valves in parallel)
    Quite ExpensiveExcellent-Have power supply or air source
    -Can be remotely set and displayed
    -Generally used in self-operated steam pressure reducing valves or occasions that cannot be met by a pneumatic control valve, suitable for occasions where the flow rate changes greatly.
    Upstream Pressure: 8~14kg/cm2
    Downstream Pressure: 5 kg/cm2
    Flow Rate: 0.5~10t/h
    Requirement: Precise/accuracy control
    Control Valve A Select Valve Size:  DN40
    (Input Signal: 4~12.55mA)
    Control Valve B Select Valve Size:  DN100
    (Input Signal: 11.5~20mA)

    The parameters of the steam pressure regulator should be indicated when ordering

    1. Model
    2. Nominal diameter × seat diameter
    3. Nominal pressure
    4. Connection type
    5. The material and surface hardening treatment requirements of the valve body and internal components
    6. Medium name
    7. Medium working temperature
    8. The inlet pressure and adjusting range
    9. Pressure setting point and adjustment range at the outlet (if for control upstream pressure, only required in items 7 and 8)
    10. The maximum, normal, and minimum flow values per hour of the equipment
    11. Special requirements, free oil, free bronze etc.

    The above is the selection of three different types of steam pressure reducing valves summarized by our company’s technicians through years of selection and application experience. THINKTANK, as a professional manufacturer in the field of high-end control valves and pressure regulators. The brand’s partners and after-sales rapid response center, through years of experience in design, assembly, transformation, maintenance, and debugging, absorb innovation in the field of control valves and provide customers with a full range of fluid control solutions. Products are widely used in petroleum, chemical, power power, shipbuilding, food, medicine, building, machinery supporting industries. The main products include globe control valves, pressure reducing valves, safety valves, self-operated pressure regulators, etc. We can provide carbon steel, alloy steel, stainless steel, super duplex stainless steel, and special alloys such as MONEL and other materials. The product temperature ranges from -196℃ to 650℃.

    For more details, please contact us or log in to the company’s official website for consultation <https://cncontrolvalve.com>

    best control valves in china
    steam pressure regulating valve

    Final Thoughts of PRV Station

    In this post, you have learned the most typical solutions for steam pressure reducing, and how to install the split range control valve for your application. If you are interested in more knowledge about control valves and regulators, please just click the following posts.

    Learn All About Pressure Control Valves

    Pressure control valves are more and more popular used for a natural gas applications, THINKTANK has participated in more than 10 large natural gas plant projects, not only has rich experience in type selection but also provides end-users with more cost-effective pressure control valves while controlling costs.

    Self-operated pressure regulators

    Nowadays, there are two types of self-operated pressure regulators, direct-acting self-operated pressure regulators, and pilot-operated pressure regulators.

    Self-operated temperature regulators

    Self-acting temperature control valves also known as self-operated temperature regulators, it doesn’t need any external power sources to regulate the temperature of process streams, tanks, and various systems. THINKTANK’s self-operated temperature regulators are often used for boiler temperature adjustment. It can maintain a linear functional relationship between temperature and valve opening.

    Self-operated differential flow control valves

    ZZC, ZZV self-operated differential (micro) pressure regulator is not needed to require external energy, and differential (micro) pressure can be adjusted in sections, ranging from 50mm.w.c to 0.1MPa. It has a wide range of uses and can be used in industrial combustion furnace systems to control the ratio of two materials, such as gas and air, to achieve ideal combustion.

    For more information, you can refer to this post. Everything knowledge you can learn for your project.

    Facebook
    Twitter
    LinkedIn
    Pinterest
    Print
    Picture of Will Don

    Will Don

    After earning my bachelor's degree in mechanical engineering from Zhejiang Normal University in 2008, l was fortunate enough to begin my career with Siemens, Fisher, and YTC, focusing on control valve accessories. Over the past dozen years, l've poured my heart and energy into understanding technology and fluid solutions for control valves.
    Now, as the marketing director for THINKTANK, a trusted branch of the Taiwan STONE valve group, I can't help butf eel proud of how far we've come. Our knowledge isn't just reaching professionals like engineer and valve distributors; it's also inspiring the next generation of automation college students.
    l genuinely hope you're enjoying our articles and finding them helpful.Your thoughts, questions, and feedback mean the world to me, so please don't hesitate to reach out to marketing[at]cncontrolvalve.com. Whether you're a seasoned expert or just curious about the field, I'm here to connect, share, and learn together.

    All Posts »

    I am the author of this article, and also the CEO and marketing director of THINKTANK, with 15 years of experience in the industrial valve industry. If you have any questions, you can contact me at any time.

    Contact Us

    Just fill out your name, email address, and a brief description of your inquiry in this form. We will contact you within 24 hours.

    The Latest News
    3 functional pressure vacuum valve

    3-Function Pressure Vacuum Valve

    The 3-Function Pressure Vacuum Valve improves on the basic functionality of an air vent head by adding a nitrogen gas preservation feature. It opens at ...
    Read More
    spring return electric actuated ball valve fail safe

    Spring Return Electric Actuator: Technical Principles, Applications and Common Valve Types

    The Spring Return Electric Actuator is a critical device for ensuring safety in high-risk environments such as tunnels, subways, marine applications, and other areas where ...
    Read More
    pilot operated breather valve

    Case Study: How to Select a Suitable Breather Valve to Handle Back Pressure

    In industrial storage tank applications, it is critical to select the right pressure and vacuum relief valves (PVRV) to ensure the safe operation of the ...
    Read More
    axial piston high pressure pump

    High Pressure Pumps Axial Piston Pumps

    In the past 5 years, we made our HPR/HPH series axial piston pumps as OEM products for a well-known brand. These pumps have been successful ...
    Read More
    breaker valve manufacturer

    VB14 and VB21 Vacuum Breaker Installation

    VB14 Vacuum Breaker Description VB14 is a small special vacuum breakers used in condensing vapour/steam or liquid systems, and it made of Brass material, and ...
    Read More
    common valve abbreviation guide

    Common Valve Abbreviation Guide

    In industrial manufacturing and instrument maintenance, you’ll see many abbreviations for valves. It’s important for engineers, maintenance people, and students to know these abbreviations because ...
    Read More
    spray & fuse coating

    Comprehensive Technical Guide on Hard Coating For Severe Service Valve

    One of the most effective ways to improve the durability and performance of valves in in severe service environments, where valves are work at extreme ...
    Read More
    dosing valve DN100 lime dosing system

    What is a Lime Dosing Valve and How Does It Work

    In the world of water treatment and chemical processing, it’s important to control lime dosing accurately. Getting the pH right and avoiding lime blockages can ...
    Read More
    concentrated solar power schematic

    Selection and Application of Molten Salt Control Valves

    In recent years, as the environmental impact of traditional energy sources such as coal and petrochemicals has become more and more of a concern, there ...
    Read More

    Contact Us

    With expertise in valves and rich experience in the oil&gas, chemical industry, textile mills, power plants, and sugar mills. THINKTANK has become the premier manufacturer of next-generation precision control valves.

    With a customer base that includes over 42 of the world’s leading engineering&contractors and international valve brands, THINKTANK Valves offers cost-effective valves that help our customers achieve automated process control without paying high prices.

    Why are more and more international valve brands choosing THINKTANK for OEM service?

    Brand is reputation, which not only requires high valve technology, but also great comercial support and fast response after-sales service and delivery time. They will not gamble their brand on an unknown product

    Get an Instant Quote

    Avoid your inquiry is delay response, please enter your WhatsApp/Wechat/Skype along with the message, so we can contact you at the very first time.

    We will reply you within 24 hours. If for urgent case, please add WhatsApp: +86 185 1656 9221, or WeChat: +86 199 2125 0077. Or call +86 189 5813 8289 directly. 

    Get An Instant Quote

    Joy Preview

    Get An Instant Quote

    We will reply you within 24 hours. If for urgent case, please add WhatsApp: +86 199 2125 0077, or WeChat: +86 199 2125 0077. Or call +86 189 5813 8289 directly. 

    Direct to Control Valve Factory With Competitive Price & Reliable Quality

    Joy Preview
    Joy Preview

    Get An Instant Quote

    Just leave your name, email, and simple message or requirements, We will contact you within 1 hour.

    WhatsApp: +86 199 2125 0077

    Skype ID: sowell85

    Wechat ID: +86 199 2125 0077