Gate valves are a common type of valve in industrial pipelines, primarily used for shutting off the flow of fluids. Based on the design of the gate and the sealing method, gate valves can be divided into wedge gate valves and parallel gate valves. Although these two types of gate valves serve similar purposes, there are significant differences in their structure, working principles, and application scenarios. 1. Valve plate design Wedge Gate Valves The gate of the wedge gate valve is wedge-shaped, and the contact surface between the gate and the seat is inclined. When the valve is closed, the wedge-shaped gate wedges into the seat, creating a tight seal. The wedge design enhances the sealing effect through the wedging action. Depending on the working conditions, the wedge gate valve can be designed as a rigid wedge, elastic wedge, or double parallel wedge. The rigid wedge gate has a simple structure but may jam due to thermal expansion in high-temperature conditions; the elastic wedge gate can adapt to temperature changes through deformation, reducing the risk of jamming. Parallel Gate Valves The valve plate of the parallel gate valve features a parallel double-plate structure, with the plates making parallel contact with the seat rather than wedging in. When the valve is closed, the valve plates are pressed against the seat by the pressure of the medium or external force, achieving a seal. The parallel design reduces the impact of thermal expansion on sealing, making it less likely to experience sticking due to temperature changes. 2. Sealing Method Wedge Gate Valves Wedge gate valves achieve sealing through the wedging action of the gate. When closed, the wedge-shaped gate makes tight contact with the seat, ensuring stable sealing performance even under high temperature and high pressure conditions. One advantage of the wedge design is that it can provide good sealing even without media pressure, thanks to the mechanical wedging action. Therefore, wedge gate valves are particularly suitable for applications requiring high sealing performance, such as steam and high-temperature fluids. Parallel Gate Valves The sealing of the parallel gate valve relies on the pressure of the medium or external force. If the medium pressure is low, the sealing performance may not be as effective as that of the wedge gate valve. The parallel design is typically used for low-pressure conditions, but some parallel gate valves utilize spring or lever mechanisms to assist with sealing. The parallel double-plate design of the parallel gate valve can adapt to temperature changes, preventing it from seizing due to thermal expansion like the wedge gate valve. 3. Operating Torque Wedge Gate Valves Due to the wedge design, the gate wedges into the seat when closed, requiring a larger torque for opening and closing. This is especially true in high-pressure conditions, where the friction between the gate and the seat increases, making the operation relatively laborious. For ap...

Wedge gate valves are a common type of gate valve, with the gate designed in a wedge shape, used to cut off or allow the flow of fluid in pipelines. Due to their excellent sealing performance, wedge gate valves are particularly suitable for harsh conditions such as high temperature and high pressure, and are widely used in industries like oil, natural gas, chemicals, and power generation. 1. Working Principle The core component of a wedge gate valve is a wedge-shaped gate. When the valve is closed, the gate descends gradually along the stem's movement, creating a wedging seal with the seat. Due to the wedge design, the gate not only relies on vertical pressure when closing but also makes close contact with the seat through the wedging action, ensuring that fluid does not leak. When the valve is fully opened, the wedge gate completely separates from the seat, allowing fluid to flow through the valve unobstructed. This makes wedge gate valves very suitable for on/off operations, but not ideal for flow regulation. 2. Structural Characteristics (1) Wedge-shaped gate: The gate is wedge-shaped and can be designed as a rigid wedge, elastic wedge, or double-parallel wedge. The rigid wedge structure is simple and sturdy, but under high temperatures, the valve may seize due to thermal expansion. The elastic wedge design allows the gate to slightly deform with temperature changes, accommodating expansion and preventing jamming. (2) Bidirectional sealing: Wedge gate valves are generally designed with bidirectional sealing, meaning that regardless of the direction of fluid flow, the valve can achieve effective sealing when closed. This feature enhances their flexibility in complex piping networks. (3) Unobstructed in fully open state: When the valve is fully opened, fluid flows through the valve with minimal resistance, reducing energy loss and turbulence. This is particularly important in applications requiring high flow transmission. 3. Advantages (1) Excellent sealing performance: The wedge design generates significant sealing force between the gate and the seat, giving wedge gate valves superior sealing performance, especially in high temperature and high pressure conditions. (2) High temperature and high pressure resistance: Wedge gate valves are commonly used in high temperature and high pressure environments, particularly in steam systems and hot oil transmission where there are significant temperature differences. The wedge design effectively addresses thermal expansion issues caused by temperature variations. (3) Sturdy structure: Wedge gate valves have a relatively simple and robust structure, making them easy to maintain and suitable for long-term use. 4. Application Scenarios (1) Oil and gas industry: Wedge gate valves are commonly used in pipelines for transporting oil and gas, especially in high-pressure pipelines and long-distance transmission networks. (2) Chemical industry: Wedge gate valves are often used in chemical installations to ensure ...

Recently, DERVOS successfully completed a local project in Singapore, providing high-quality globe valve products that ensured efficient operation and safety throughout the project. Background The client for this project was a Singapore-based on-site repair and maintenance company, primarily responsible for the daily maintenance and emergency repairs of industrial facilities. Their core requirement was to provide reliable isolation valves for high-pressure steam systems, ensuring efficient and safe operation under high-pressure and high-temperature conditions. Facing issues such as valve aging and high maintenance costs, the customer urgently needed a solution that could provide long-term stable performance. Product Features To meet the customer's strict requirements for steam medium management, we provided a high-pressure steam isolation globe valve. This valve is specifically designed for steam isolation, featuring excellent high-pressure resistance. It is manufactured using precision machining processes to ensure stable sealing and long-lasting performance, even under high-temperature and high-pressure conditions. The valve not only meets strict international standards but also underwent multiple tests at the project site, demonstrating exceptional performance. Project Results The globe valve was successfully installed and put into operation. The client reported that their high-pressure steam system is running smoothly, with more stable and safer operation. The precise control of the valve not only improved the efficiency of maintenance work but also significantly reduced system failures and safety risks. The client highly praised the performance and service of our products, stating that our solution greatly supported their daily maintenance and emergency response capabilities. The success of this project has not only enhanced the client's maintenance efficiency and system safety but also laid a solid foundation for future cooperation between both parties. We are proud to have been involved in this project and look forward to continuing to provide high-quality fluid control solutions for our clients in the future.

In industrial piping systems, valves are critical components for controlling fluid flow, directly impacting the safety and operational efficiency of the system. In certain specific working conditions, a single valve may not be sufficient to meet process requirements and safety standards. Therefore, double valves (also known as a double valve system) are required to enhance the system's reliability and safety. 1. Typical Working Conditions for Double Valve Installation (1) Control of High-Risk Media When handling toxic, hazardous, flammable, explosive, or corrosive media, leaks in the pipeline system can lead to severe safety incidents. To ensure safety, double valves are typically installed in these cases. The double valve system provides dual sealing, so if one valve fails, the other valve can still effectively prevent media leakage, reducing risk. (2) Isolation of Critical Process Flows In certain critical process flows, absolute isolation is required to prevent media mixing or backflow. In such cases, double valves provide a higher level of isolation. The two valves are typically arranged in series, so when the main valve is closed, the second valve continues to provide isolation protection, ensuring complete separation of media inside and outside the system. (3) Convenience for Maintenance and Repair In conditions requiring frequent maintenance or repair, a double valve configuration enhances the safety and efficiency of maintenance operations. For example, when servicing a section of the pipeline, both valves in the series can be closed first. This allows the intermediate section to be emptied or repaired, ensuring no leakage occurs during maintenance and safeguarding personnel and equipment. (4) High-Pressure or High-Temperature Conditions In high-pressure or high-temperature conditions, a single valve may struggle to withstand extreme process conditions over time, leading to potential seal failures or material degradation. Implementing a double valve system not only provides higher safety redundancy but also helps to distribute pressure or temperature loads, thereby extending the lifespan of the valves. (5) Regulatory or Standards Requirements In certain industries or regions, regulations or standards mandate the use of double valve systems to ensure safety. For example, in natural gas transportation or chemical production, some countries' laws require the installation of double valves to prevent medium leakage and environmental contamination. These regulations are primarily based on risk assessments specific to the industry and aim to ensure the safety and reliability of the system. 2. Advantages of a Double Valve System (1) Double Safety Assurance A double valve system provides dual sealing and isolation functions. Even if one valve fails, the other can maintain the integrity of the system, thereby reducing risks. (2) Enhanced System Reliability By distributing the operational load, a double valve configuration can reduce wear and aging ...

In the valve industry, ball valves are widely used in various fluid control systems due to their simple structure, excellent sealing performance, and ease of operation. Based on the connection method, ball valves can be classified into threaded ball valves and flanged ball valves. 1. Connection Method Threaded Ball Valves: Threaded ball valves connect to pipelines using either internal or external threads and are typically used in small-diameter pipeline systems. The advantage of threaded connections lies in their easy installation, compact design, and minimal space requirements, making them especially suitable for confined spaces. Threaded ball valves are commonly used in low and medium-pressure systems and are ideal for fluid control in residential, commercial buildings, and light industrial equipment. Flanged Ball Valves: Flanged ball valves are connected to pipelines through flanges and are suitable for medium to large-diameter pipelines. Flange connections offer higher strength and stability, allowing them to withstand higher pressures and temperatures. As a result, they are commonly used in heavy industries, chemical processing, oil, natural gas, and other applications involving high pressure, high temperature, or corrosive media. Flange connections also facilitate easy disassembly and maintenance but require more installation space. 2. Sealing Performance Threaded Ball Valves: Threaded ball valves typically use soft sealing materials such as polytetrafluoroethylene (PTFE), offering excellent sealing performance, making them suitable for gases, liquids, and other media. However, under high-pressure and high-temperature conditions, threaded connections may pose a risk of leakage, and their sealing effectiveness is generally slightly weaker than that of flanged ball valves in demanding operating conditions. Flanged Ball Valves: Flanged ball valves typically utilize metal or composite seals, providing more reliable sealing performance, especially under high-pressure, high-temperature, or corrosive media conditions. The sealing of flange connections is more stable, effectively preventing leakage. 3. Installation and Maintenance Threaded Ball Valves: Threaded ball valves are easy to install, requiring only tightening to complete the connection, making them ideal for quick installation in small systems. However, once the threaded connection is secured, it may loosen due to thermal expansion and contraction or vibration of the pipeline, leading to potential leakage risks. During maintenance, if a threaded ball valve needs to be replaced, it may affect the pipeline system and even require reconnection of the entire pipeline. Flanged Ball Valves: Flanged ball valve installation requires the use of flanges, bolts, and gaskets, making the installation process more complex. However, flange connections offer higher robustness and reliability. During maintenance, flanged ball valves can be easily disassembled, replaced, or repaired without affecting the ...

The Bevel Gear Knife Gate Valve is a valve specifically designed for handling complex media containing solid particles, sludge, and similar substances. It is highly regarded in industrial applications for its reliability and efficiency. 1. Structural Characteristics of Bevel Gear Knife Gate Valve The structural design of the bevel gear knife gate valve prioritizes durability and reliability, and is mainly composed of the following components: (1) Valve Body: Typically made from high-strength materials such as cast iron, stainless steel, or other corrosion-resistant alloys to meet the demands of various working conditions. The internal flow path of the valve body is designed to be straight, reducing flow resistance as the medium passes through, which helps to increase flow rate and minimize wear. (2) Knife Gate: The knife gate is the core component of the valve, featuring sharp cutting edges that can effectively cut through and isolate media containing solid particles. The knife gate is typically made from wear-resistant materials to ensure long-term use under high-wear conditions. (3) Bevel Gear Mechanism: This is a key feature that distinguishes the Bevel Gear Knife Gate Valve from other knife gate valves. The bevel gear mechanism converts rotational motion into linear motion through a set of bevel gears, driving the knife gate to move up and down. This design makes the valve easier to operate, especially in large diameter and high-pressure conditions, significantly reducing the difficulty of operation. (4) Sealing Assembly: The sealing performance of the valve directly affects its reliability and service life. The Bevel Gear Knife Gate Valve typically uses elastic materials or metal seals, with the sealing ring fitting tightly with the knife gate to ensure that there is no leakage of the medium when the valve is in the closed position. (5) Stem and Handwheel: The stem is connected to the bevel gear mechanism, and the rotation of the handwheel controls the movement of the bevel gears, thereby controlling the opening and closing of the knife gate. The stem is typically made of anti-corrosive materials and is equipped with a protective sleeve to extend its service life. 2. Working Principle of Bevel Gear Knife Gate Valve The working principle of the Bevel Gear Knife Gate Valve is relatively simple, but its design takes into account the application requirements under various complex operating conditions, ensuring the efficient operation of the valve. (1) Valve Opening: When the valve needs to be opened, the operator rotates the handwheel to drive the bevel gear mechanism. The bevel gear converts the rotational motion of the handwheel into the linear motion of the valve stem, pushing the knife gate upwards. As the knife gate rises, the internal flow path of the valve gradually opens, allowing the medium to pass through smoothly. (2) Valve Closing: When closing the valve, the handwheel is rotated in the opposite direction, and the bevel gear mechanis...