China Wuhan Grat Control Valve Co., Ltd. Company Cases

1.What is a pneumatic valve?A pneumatic valve is a device that uses compressed air to actuate (open, close, or proportionally control flow through) a valve. Key components include the valve body, valve stem, trim (e.g., ball, disc, plug), seals, and a pneumatic actuator. Compressed air acts on a piston or diaphragm within the actuator, generating linear or rotary motion to position the closure element. Due to their advantages of rapid actuation, ease of automation, and reliable performance, pneumatic valves are widely used in critical industries such as chemical processing, oil & gas, power generation, and natural gas, where they play a vital role in complex process control. 2. Working Principle AnalysisPneumatic valve operation begins at the air preparation unit (typically filters, regulators, and compressors), which intakes ambient air, removes impurities/moisture, and pressurizes it into compressed air. This air is distributed via piping to pneumatic actuators (diaphragm types for linear motion, piston types for high-force/stroke applications).For example: When air enters a diaphragm actuator's chamber, the diaphragm elastically deforms under pressure, displacing the valve stem. The stem mechanically transfers this motion to position the trim (e.g., plug, ball, or disc), thereby opening, closing, or modulating flow through the valve body. Normally Open (NO) Pneumatic Valves: Default state: Spring force holds the closure element (e.g., plug) open, ensuring uninterrupted fluid flow. Upon actuation: When a control signal (e.g., solenoid valve energizing) applies air pressure to the actuator, the piston/diaphragm overcomes spring force, driving the stem to move the closure element to the closed position and shut off flow. Normally Closed (NC) Pneumatic Valves: Default state: Spring force maintains the closure element in the closed position, blocking flow. Upon actuation: Air pressure applied to the actuator compresses the spring, retracting the stem to open the closure element and permit flow. The operating principle of piston pneumatic actuators similarly relies on differential air pressure across the piston. When pressurized air is applied to one side of the piston chamber, it generates linear force to drive the piston rod. This motion is mechanically transmitted through the valve stem to position the closure element (e.g., plug, ball, or disc). Piston actuators deliver higher thrust outputs than diaphragm types, making them ideal for large-bore valves and high-pressure applications where greater actuation force is required. 3.the implementation of the adjustment function Certain pneumatic valves incorporate flow regulation capabilities beyond basic on/off control. This is achieved through specialized closure element designs like V-port balls or eccentric rotary plugs. V-port Ball Operation:Rotation of the ball alters the V-shaped orifice area between the ball and seat. As the ball rotates from 0° to 90°: Opening phase: Flow area rotation angle → Flow rate increases Closing phase: Flow area (90° - rotation angle) → Flow rate decreases Control Mechanism:Precise regulation requires: Positioning system: A valve positioner converts control signals (4-20mA/pneumatic) into precise air pressure modulation. Actuator response: Modulated air pressure drives the actuator to achieve target rotation angle. Flow characterization: The V-port's engineered profile provides linear/equal-percentage flow characteristics. A thorough comprehension of pneumatic valves operational principles and performance characteristics – including rapid actuation, precise flow control, and fail-safe functionality – enables engineers to: Optimize process parameters (e.g., response time, pressure setpoints). Enhance production efficiency through reduced cycle times. Lower operational costs via minimized energy consumption and maintenance downtime. Ensure production chain stability with reliable shutoff and leakage control meeting product standards. > Wuhan Grat Control Valve CO.,LTD

Electric actuator slowing down? Daily near+100 cycles & two root causes + fixes.In industrial automation systems requiring 100+ daily cycles, electric actuator slowdown can cripple productivity. A real-world example: An actuator’s cycle time degraded from 15-30s to 45+s within 8 months, costing 20+ minutes of downtime daily. While the OEM denied warranty coverage, our engineering team diagnosed and fixed the issue—here’s how. In a reverse osmosis (RO) water treatment system, a DN150 butterfly valve with a 100 Nm electric actuator showed significant performance degradation under high-frequency cycling (80-90 actuations/day)—despite otherwise mild operating conditions. Medium: Purified water (non-abrasive) Pressure: Constant 1.18MPa Valve configuration: DN150 butterfly valve with 100 Nm torque motorized head. Technical team diagnosis: two core reasons. By analyzing the valve body structure, operating condition data and equipment configuration, we found the following problems:     1.Severe Seat Wear Causing Increased Actuator Torque Demand The cycle life of national standard (GB) butterfly valves is typically 20,000 to 30,000 cycles, while European standard (e.g., EN) valves achieve 40,000 to 60,000 cycles. The customer operates this valve 80 times per day, totaling nearly 20,000 cycles within 8 months. This usage approaches the end of the valve seat's expected service life.   Consequences of friction: Increased friction between the seat and disc results in a sustained rise in actuator torque requirement and longer stroke times.   2.The actuator was significantly under-torqued for the application — a classic case of a small horse pulling a heavy cart The DN150 butterfly valve is usually equipped with a motorized head with 200 Nm torque, but the customer only configured it with 100 Nm.   Direct impact: Long-term overload of low-torque actuators accelerates component aging and further slows down switching speeds.  Optimal Solutions for Valve Maintenance & Performance Enhancement Option 1: Replace the Worn Valve Seat If the valve seat is found to be severely worn, directly replace the valve seat with a high wear-resistant material to restore the performance of the valve body and prolong the service life.  Option 2: Upgrade to a Higher-Torque Electric ActuatorIf the valve seat is intact, upgrade to a 200 Nm electric actuator to ensure proper torque matching and prevent overloading. Essential Maintenance Guidelines for High-Frequency Valve Operation 1.Inspect valve seat wear regularly. For valves with over 50 daily cycles, quarterly inspections are recommended. 2.Ensure proper actuator torque matching to prevent premature wear caused by undersized torque of actuators. 3.Select durable valve bodies, such as EN-standard butterfly valves, to significantly extend maintenance intervals. Grat's Service CommitmentAs a professional control valve service provider, we are committed to delivering solutions until the problem is fully resolved. Regardless of warranty status, we offer complimentary technical diagnostics and tailored solutions to ensure efficient and stable production operations. > Wuhan Grat Control Valve CO.,LTD

1.Working PrincipleThe explosion-proof electric plug valve consists of a plug, valve body, sealing components, and an electric actuator. Upon receiving a control signal, the actuator rotates the plug to precisely regulate flow—enabling open, close, and controlling functions. Its explosion-proof capability is achieved through robust design and manufacturing processes, effectively isolating ignition sources (e.g., sparks or high temperatures) in flammable oil and gas environments. 2. Key Features of Explosion-Proof Electric Plug Valves   Quick-Acting OperationRequiring only a 90° rotation to achieve full open/close positions, these valves enable rapid response - a critical advantage in time-sensitive oilfield operations where process efficiency is paramount. Low Flow ResistanceThe straight-through flow path design minimizes flow turbulence, resulting in:• Reduced pressure drop across the valve• Lower system energy consumption• Improved overall pipeline efficiency Superior Sealing PerformanceFeaturing advanced sealing materials and optimized geometry, our valves ensure:• Zero-leakage performance• Reliable operation across varying pressure/temperature conditions• Extended service life High-Pressure CapabilityEngineered to withstand extreme wellhead pressures ,the robust construction guarantees operational safety in demanding downhole environments. 3. Critical Applications in Oil & Gas Operations Crude Oil Transmission & Wellhead Control• Provides immediate shut-off and precise flow regulation in high-pressure flow lines• Prevents hydrocarbon leaks and wellhead blowouts through fail-safe design• Self-cleaning seal mechanism minimizes particulate fouling in sandy/high-viscosity crude applications Gas Processing & Gathering Systems• Ensures reliable flow diversion during gas separation/compression cycles• Maintains pipeline pressure stability preventing leakage • Explosion-proof construction for methane-rich environments Waterflood & Fracturing Operations• Regulates high-pressure injection fluids • Enhances EOR efficiency through accurate flow control • PTFE-lined stainless steel construction resists HCl/HF acids in stimulation fluids Emergency Shutdown (ESD) SystemsLinked with the automatic control system, the pipeline can be quickly cut off in case of distress to prevent the spread of the accident. 4.Industry Outlook & Technological Evolution As offshore and remote oilfield developments progress, operational demands for equipment safety and reliability are reaching unprecedented levels. Explosion-proof electric plug valves are evolving through three key technological vectors: smart Integration, enhanced performance, sustainable solutions   For detailed technical specifications or application engineering support, our technical specialists are available for consultation. Contact us to discuss your project's specific requirements. > Wuhan Grat Control Valve CO.,LTD

In October 2020, GRAT supplied its hard-sealed electric control butterfly valve for a flue gas desulfurization (FGD) system at a Steel Group in Jinan, China.The process involves gas-liquid reactions, requiring corrosion-resistant and precise control valves to ensure stable operation. Flue gas desulfurization is key to controlling SO₂ emissions in industries like steel, with wet FGD being the most common method. The valve is used for coke oven gas concentration regulation, handling SO₂, SO₃, CO₂, and other process gases in a demanding industrial environment, and achieves over 90% desulfurization efficiency. Here are the key specifications of the GRAT valve used in this application: Medium: Process gas containing SO₂, SO₃, O₂, N₂, CO₂, H₃O Pressure: PN16 Size: DN350-DN800 Material: SUS304 stainless steel (disc & seat), WCB (body) Connection: Wafer-style Actuation: 4-20mA proportional control, smart electric actuator with local/remote switching & LCD display Power Supply: AC380V With its smart electric actuator, the GRAT valve enables precise and automated gas flow regulation, ensuring stable SO₂ removal while simplifying system operation and monitoring. As industries continue to seek efficient and reliable solutions for emission control, GRAT remains committed to providing durable, high-performance valves that support long-term operational stability in demanding environments. - GRAT Electric Control Butterfly Valve -

Automotive parts production often requires high-temperature and high-pressure steam generated from industrial boilers. These boilers rely on boiler gas, a flammable medium that demands strict control to ensure operational safety and efficiency. Any leakage or malfunction in the gas supply system could lead to production disruptions or severe safety hazards.In 2023, GRAT supplied a DN400 pneumatic on-off ball valve with a hydraulic manual override for a boiler gas supply system in a major automotive parts production facility. Below are the key technical specifications that make it fit for this challenging application. Application Site: Boiler gas supply system Industry: Automotive parts manufacturing Function: Medium switching and shut-off Product Name: DN400 Pneumatic On-Off Ball Valve with Hydraulic Manual Override Material: WCB (Carbon Steel) Connection Type: Flanged Connection Nominal Pressure: 1.6MPa Medium: Boiler Gas Power Source: Compressed Air Design Life: 5-10 years Designed for seamless medium switching and shutdown, this valve ensures stable and safe operation under demanding industrial conditions. GRAT’s pneumatic on-off ball valve has proven to be a reliable and high-performance solution for the automotive manufacturing sector’s fuel supply needs. By integrating advanced pneumatic control with durable construction, GRAT continues to support industrial applications with safe, efficient, and long-lasting valve solutions. > GRAT  Pneumatic On-Off Ball Valve 

Valves are essential components in industrial systems, ensuring safe and efficient operations. In this case study, we examine the application of GRAT's electric butterfly valve in a hydropower station, showcasing its reliability and performance in a water control system.       Application Case: GRAT Electric Butterfly Valve in Hydropower Stations   Application: Hydropower Station Dam Flow Release Medium: Water (Ambient Temperature) Nominal Pressure: PN16 Sizes: DN100 / DN150 Material: SUS304 Stainless Steel Connection Type: Wafer Style Operation Mode: On-Off Power Supply: DC24V / DC220V Operational Date: August 2018 Location: Fujian, China   This electric butterfly valve is used to control the water discharge at a hydropower station dam, playing a crucial role in environmental management. Constructed with SUS304 stainless steel, it ensures long-term durability and resistance to corrosion in a water-based environment. Key Benefits: Durable & Reliable: Made from SUS304 stainless steel, ensuring long-lasting performance. Precise Control: On-off operation enables accurate flow regulation. Energy-Efficient: Low power requirements (DC24V / DC220V) for cost-effective operation. Long Service Life: Designed to last for 5 years with minimal maintenance.   GRAT’s electric butterfly valve provides a reliable solution for water flow control in hydropower applications. Its durability, energy efficiency, and ease of installation make it ideal for demanding environments like dams and hydropower stations.     > GRAT Wafer Electric Butterfly Valve

The Electric Plug Valve is engineered for use in high-pressure applications like cementing and fracturing in the oil and gas industry. Known for its compact design and easy maintenance, it operates with a small torque and offers rapid opening, making it the ideal valve for critical operations in harsh environments. Key Specifications: Rated Pressure: 2,000~15,000psi Nominal Diameter: 2” & 3” Working Temperature: LU Pressure Class: PSL1~4 Performance Class: PR 1~2 Material Grades: AA, BB, CC, DD, EE, FF Operating Medium: Petroleum, Natural Gas With its high precision and reliable sealing between the plug and seat, the motorized plug valve provides secure control even in demanding conditions. It is ideal for remote control and automated operations, eliminating the need for personnel to operate manually in hazardous areas. Explosion-proof Electric Actuator: Designed to meet Ex db IIC T6 Gb standards, this actuator ensures safe operation in explosive atmospheres like methane or hydrogen sulfide. With an output torque range of 50~4000N·m, it covers valves up to DN300 and operates in IP67 environments, making it perfectly suited for underground operations. The actuator is a game-changer for operations requiring high safety standards, offering remote control and real-time data integration for process monitoring, fault alerts, and operational optimization. Key Benefits: Enhanced Safety: Reduces risks by enabling remote control, minimizing human exposure to hazardous environments. Increased Efficiency: Fast opening and closing, enhancing workflow during high-frequency operations. Smart Integration: Supports data collection, fault monitoring, and system optimization via digital platforms. The electric motorized plug valve, paired with our explosion-proof actuator, exemplifies the integration of automation, safety, and performance—key elements for enhanced operation control in oilfield and high-pressure gas environments. For further inquiries or pricing details, please feel free to contact us or visit our inquiry page. We look forward to collaborating with you.

The chemical industry operates under stringent conditions, with safety, precision, and reliability at the forefront of every process. Key to maintaining these standards are components like control valves, which are integral in handling aggressive media, high pressures, and extreme temperatures. This case study details the application of the GRAT Pneumatic V-Type Control Ball Valve in steam regulation within a chemical production environment, demonstrating its effectiveness in managing the specific demands of saturated steam control. Steam, particularly saturated steam, is frequently used in chemical processes for heating, sterilization, and other applications. However, saturated steam poses unique challenges for valve control. Not only does it require robust construction to handle high temperatures and pressure, but any leaks or malfunctions could have severe safety implications, including exposure risks and potential harm to system stability.     The GRAT Pneumatic V-Port Control Ball Valve is designed to meet these rigorous requirements, specifically tailored for precise flow regulation and durability in challenging conditions.   Key Features and Advantages:   Enhanced Safety: With its high-grade materials and fail-safe design, the GRAT valve minimizes risks associated with steam leaks and offers reliable performance in case of emergencies. Precise Control: The V-Port design enables more precise modulation of steam flow compared to traditional ball valves, improving overall process control. Longevity: The hard sealing with Stellite significantly extends the lifespan of the valve, even under continuous exposure to high temperatures and pressures. Efficiency: Consistent steam flow regulation leads to optimized energy use, reducing operational costs over time.       Specifications: Size: DN50 Material: SUS304 stainless steel Sealing: Hard seal with Stellite overlay Medium: Saturated steam Control Signal: 4-20mA Operation Mode: Single-acting The successful application of the GRAT Pneumatic V-Type Control Ball Valve in a chemical industry setting highlights its capability to handle the unique challenges posed by saturated steam. Its robust construction, precise control features, and fail-safe design make it a valuable asset in hazardous environments where both safety and performance are paramount.   As the chemical industry continues to push boundaries in process demands, reliable and specialized components like the GRAT V-Port valve will remain indispensable.       > GRAT Pneumatic V-Type Control Ball Valve

As environmental awareness grows, wastewater treatment has become essential. Electric V-type control valves offer precise flow regulation, making them invaluable in sewage treatment. Key Features of Electric V-Type Control Valves Precision Control: These valves use advanced actuators for accurate flow regulation, even in high-pressure or high-temperature conditions. Corrosion Resistance: Built with durable materials, they withstand harsh chemical environments, and their robust actuators ensure longevity. Ease of Maintenance: Simple design allows easy adjustments, with real-time monitoring for quick issue detection.     Practical Application Cases   Next, let's illustrate the application of GRAT electric V - type regulating valves in the sewage industry through three practical application cases.   Case 1   A certain urban sewage treatment plant needed to precisely control its sewage treatment process to ensure that the sewage could meet the discharge standards. They chose electric V - type regulating valves and applied them to key links such as the influent pump house and the aeration tank. Through precise flow control, the sewage treatment plant successfully achieved stable adjustment of water quality and improved the efficiency of sewage treatment. At the same time, due to the high corrosion resistance of the electric V - type regulating valves, they exhibited excellent performance and reliability in the sewage environment.   Case 2   A large industrial park has multiple enterprises, and its sewage discharge requires strict treatment and monitoring. To achieve this goal, the park adopted electric V - type regulating valves to control the sewage flow. Through precise flow control, the stable operation of the sewage treatment equipment was ensured, and the sewage discharge could be effectively monitored and controlled. This is not only beneficial to environmental protection but also to the sustainable development of enterprises.   Case 3 A large river treatment project needed to effectively treat and discharge sewage. To achieve this goal, the project side adopted electric V - type regulating valves to control the sewage flow. Through precise flow control, the project side could ensure the stable operation of the sewage treatment equipment and effectively monitor and control the sewage discharge. This is not only beneficial to environmental protection but also to the sustainable development of the city.   Conclusion GRAT electric V - type regulating valves play an important role in the sewage industry. They can not only achieve precise flow control, improve the efficiency and quality of sewage treatment, but also possess characteristics such as high corrosion resistance, durability, and easy maintenance, meeting the high requirements of the sewage treatment industry.  

In aggressive chemical industries, where equipment is exposed to highly corrosive substances, ensuring durability and reliability is paramount.   GRAT’s corrosion-resistant electric control valve, installed in a facility processing chlorine gas with fluoride ions, is specifically designed to withstand such challenging conditions. Operating effectively within a temperature range of 0 to 120°C, this valve showcases both robust construction and advanced technology.     Key Features and Advantages: Exceptional Corrosion Resistance: Constructed with a cast steel body and core fully lined with F46, the valve provides superior protection against highly corrosive media, ensuring longevity and operational stability. Advanced Technology: Equipped with patented PPD positioning technology and high-temperature automatic cooling, the valve adapts efficiently to fluctuating operating conditions, maintaining precise control. Seamless Integration into Automated Systems: Supporting a 4-20mA communication signal and DCS compatibility, the valve enables smooth integration into plant-wide automation, enhancing process efficiency.     This specialized valve is designed to endure the extreme demands of highly corrosive environments. Below are the key technical specifications that make it fit for this challenging application. Valve Body Material: Cast steel (fully lined with F46) Valve Core Material: Cast steel (fully lined with F46) Seal: F46 Medium: Chlorine gas (with fluoride ions) Medium Temperature: 0-120°C Power Supply: AC220V Special Technology: Patented PPD positioning technology, high-temperature automatic cooling technology Flow Characteristics: Equal percentage Communication Signal: 4-20mA DCS System: Supports operation and communication with DCS systems Operation Start Date: December 2010 Expected Valve Lifespan: 3 years (safety period)   Since its commissioning in December 2010, this control valve has demonstrated consistent, reliable performance, proving its suitability for applications within harsh chemical processes. > GRAT Electric Control Valve

Thailand, strategically located in Southeast Asia, is a nation rich in oil and gas resources, with a history dating back to the mid-19th century as a producer. The country's natural gas reserves are estimated at 54.65 billion cubic meters, and oil reserves at 164 million tons, playing a pivotal role in its economic growth and reducing dependence on imported refined oil products.   In this context, the Thai oil and gas industry demands robust valve technology to ensure efficient extraction, processing, and transportation of hydrocarbons, with a focus on safety, reliability, and environmental sustainability. Valves play an essential role in Thailand's oil and gas industry, particularly when it comes to tackling the corrosiveness of oil wells, the high pressures of deep-sea drilling, and the extreme temperature conditions encountered.     A Thai customer who has long cooperated with our company is a company engaged in the development, production, and installation services of oil and gas measurement and analysis equipment. The company mainly undertakes government oil and gas design, installation, and transportation projects. Our products that meet the needs are as follows: (1) Explosion-proof electric regulating valves (V-shaped and rectangular ports) Model: EV - 50PCUN64RCFEX, EJ - 50PCUN64RCFEX Voltage: DC24V Diameter: DN50 Input and output signals: 4 - 20mA Valve body material: WCB Connection method: Flange Protection level: IP67 Explosion-proof level: Exid II BT4 Flow rate: 0 - 200m³/h

In the petrochemical heating industry, controlling steam flow in boilers demands valves with high resistance to temperature and corrosion. GRAT pneumatic control valves have been successfully applied in this setting, showcasing their durability and adaptability in regulating and shutting off boiler steam. This case highlights the exceptional performance and reliability of GRAT valves in high-temperature steam applications.       Special Features and Performance The valve’s single-acting pneumatic actuator ensures reliable operation with a quick and effective response time for both regulation and shut-off tasks.   With a robust SUS316L body, the valve provides excellent resistance to corrosion and high-temperature conditions, ensuring long-term durability and performance stability. Since its commissioning in 2008, this valve has contributed significantly to safe and precise steam flow management in the petrochemical heating process.   Technical Insights The control signal of 4-20mA enables the valve to integrate seamlessly with the DCS (Distributed Control System) for automated and remote monitoring, contributing to improved operational efficiency and system reliability. The single-acting actuator design is energy-efficient, suitable for high-demand environments where consistent and precise flow regulation is critical.     Application Details Industry: Petrochemical heating equipment Valve Type: Pneumatic control valve (single-acting) Valve Size: DN25 Body Material: SUS316L stainless steel Medium: Boiler steam Medium Temperature: 250°C Control Signal: 4-20mA Functions: Flow regulation and shut-off Operational Start Date: June 2008 Since its commissioning in 2008, the GRAT pneumatic control valve has withstood years of rigorous high-temperature steam applications, consistently delivering stable control and shut-off performance. Should you have similar requirements or questions, please feel free to contact our team for further information.   > GRAT Pneumatic Control Ball Valve