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  • DVS Slide Blind Valve Successfully Solves Sealing and Positive Isolation Challenges in Multi-Media Switching for a South African Oil Client

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Top 5 Industrial Valve Types Every Engineer Should Know in 2026
Top 5 Industrial Valve Types Every Engineer Should Know in 2026
2026-03-27

Choosing the right industrial valve type is one of the most critical decisions in system design. A poor selection—even when using high-quality valves—can lead to leakage, pressure loss, vibration, frequent maintenance, and long-term operational inefficiency. This guide covers the main industrial valve types, their applications, advantages, and limitations, along with practical insights to help you make the right valve selection for your project in 2026.   What Are Industrial Valve Types? Industrial valve types refer to different valve designs used to control, regulate, or isolate fluid flow in piping systems. Each type is engineered for a specific function—such as shut-off, throttling, or backflow prevention—and selecting the correct type is essential for system safety and efficiency.   5 Main Industrial Valve Types and Their Applications 1. Ball Valve Best for: Quick shut-off and low pressure drop Ball valves use a rotating ball with a straight-through bore. When fully open, they provide minimal resistance, making them one of the most efficient options for fluid transmission. Common applications:      ● Oil and gas pipelines      ● High-pressure systems      ● Frequent on/off operations Selection notes:      ● Full-port designs minimize energy loss      ● Metal-seated ball valves perform better in abrasive or high-cycle conditions   Avoid if:Precise flow control is required. Throttling with a ball valve can damage sealing surfaces over time.   2. Gate Valve Best for: Isolation service with minimal flow resistance Gate valves operate by lifting a gate out of the flow path. They are widely used in large-diameter pipelines where full open or full close operation is required. Common applications:      ● Long-distance transmission pipelines      ● Water treatment systems      ● High-temperature steam lines Selection notes:      ● Near-zero pressure drop when fully open      ● Wedge gate valves provide better sealing in high-temperature conditions   Avoid if:Frequent operation or throttling is required. Gate valves are not designed for repeated cycling.   3. Globe Valve Best for: Precise flow regulation Globe valves force fluid through a controlled flow path, allowing accurate throttling and stable flow control. Common applications:      ● Steam systems      ● High-temperature processes      ● Flow regulation applications Selection notes:      ● Excellent throttling performance      ● Stable operation under fluctuating flow conditions   Avoid if:Pressure drop must be minimized. Globe valves inherently create higher flow resistance.   4. Check Valve Best for: Automatic backflow prevention Check valves operate automatically based on flow directi...

Can Line Blind Valves Handle High-Temperature Steam Applications?
Can Line Blind Valves Handle High-Temperature Steam Applications?
2026-03-19

Recently, Dervos Valve helped a client in Hungary overcome a common challenge in industrial steam systems: how to safely isolate high-temperature pipelines without leakage or downtime.   Operating with saturated steam at around 250°C and exposed to temperatures as low as -39°C, the client’s system demanded a solution that was both robust and reliable. Traditional valves often failed to maintain a tight seal under such conditions, and conventional isolation methods required depressurizing the line, increasing downtime and operational risk.   To address these challenges, Dervos supplied a DN400 PN40 sliding line blind valve, engineered specifically for the project’s harsh conditions. The valve’s sliding blind mechanism allows operators to switch between flow and isolation positions without depressurizing the system, enhancing safety and efficiency during maintenance.   Built with forged 20GML steel and a metal-to-metal stainless steel sealing structure, the valve delivers reliable performance under both high-temperature steam and extreme outdoor climates. Its full-bore design minimizes flow resistance, while the worm gear manual actuator ensures smooth and controlled operation even at large sizes and high pressure ratings. Safety features such as anti-misoperation devices and protective blind plate structures further reduce the risk of errors during handling.   Since installation, the valve has enabled leak-free operation, safer maintenance procedures, and stable performance in extreme temperatures. Designed for a service life exceeding 30 years, it provides a long-term, low-maintenance solution, giving the client confidence in their steam system’s reliability and safety.   This project highlights how a carefully engineered sliding line blind valve can solve critical isolation challenges in high-temperature steam applications, combining operational safety, durability, and efficiency in one solution.

Are Gate Valves Full Port?
Are Gate Valves Full Port?
2026-03-13

In industrial piping systems, gate valves are generally considered low-resistance isolation valves. When the valve is fully open, the gate is completely withdrawn from the flow path, allowing the fluid to pass through with minimal obstruction.   However, from a strict engineering perspective, not all gate valves are classified as full port valves.   If the seat bore is equal to or very close to the pipeline internal diameter, the flow experiences little or no restriction. In this case, the valve can be considered full port (or near full port). This design is commonly used in oil and gas pipelines, water transmission systems, and other applications where low pressure drop is required.   If the seat bore is slightly smaller than the pipe internal diameter, a minor flow restriction will occur inside the valve. In such cases, the valve is more accurately described as reduced bore. This configuration is more common in smaller sizes or cost-optimized valve designs.   In engineering practice, a simple selection logic can be applied: ● If the system requires minimum flow resistance or pipeline pigging, the valve bore must match the pipeline diameter. ● If the valve is used for general isolation purposes, most standard gate valves can already meet the required flow capacity.   Therefore, a concise conclusion can be drawn: Gate valves are typically close to full port designs, but whether they are truly full bore depends on whether the seat bore equals the pipeline internal diameter.   QA   Q1: Are gate valves always full bore?Not necessarily. If the seat bore equals the pipe internal diameter, the valve can be considered full bore. If it is slightly smaller, it is classified as reduced bore.   Q2: Why do gate valves have relatively low flow resistance?When the valve is fully open, the gate is completely removed from the flow path, allowing the fluid to pass through in a nearly straight line, which results in low pressure drop.   Q3: Are gate valves suitable for high-flow pipelines?Yes. If the system requires low pressure drop, gate valves are commonly used.   Q4: Is the concept of full port the same for gate valves and ball valves?Not exactly. For ball valves, the bore size is determined by the ball port diameter, while for gate valves, it is mainly determined by the seat bore diameter.

Positive Isolation
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DVS Slide Blind Valve Successfully Solves Sealing and Positive Isolation Challenges in Multi-Media Switching for a South African Oil Client

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Product Detail

1. Challenges Faced by the Client

An oil terminal operator in South Africa, handling multiple light petroleum products such as HSD, MA, and JET-A1 within its pipeline system, encountered the following key challenges:

 

● Volatile and complex media: Aviation fuels such as JET-A1 require extremely high sealing performance; even minor leakage poses significant safety risks.

● Frequent media switching: Reliable physical isolation is required during product changeover. Conventional valves cannot achieve absolute shut-off.

● Insufficient sealing performance: Standard gate valves and ball valves present a risk of internal leakage after prolonged service.

● Strict safety requirements: The client specified a clear requirement for “zero visible leakage.”

 

2. Our Solution

To address these operating conditions, Dervos Valves supplied a Slide Blind Valve, with the following key configurations:

 

 Design Type: Slide Blind (Spectacle Blind / Line Blind)

● Switching between a solid plate and a spacer enables complete shut-off or full flow.

● Provides visual and verifiable positive isolation, meeting high safety requirements.

Sealing Design: Drip-tight Construction

● Effectively prevents leakage and evaporation of light hydrocarbons.

● Suitable for stringent sealing requirements of aviation fuel service.

Pressure Rating and Standards:

● Class 150, in accordance with ASME B16.34

● Flanged connection: Raised Face (RF)

Material: ASTM A105 Forged Steel

● Offers high mechanical strength and pressure resistance.

● Well-suited for petroleum service, balancing cost efficiency and reliability.

Operation: Worm Gear (Turbine Drive)

● Suitable for large diameter (10") applications, reducing manual effort.

● Enhances operational stability and safety during switching.

3. Results Achieved

In actual operation, the slide blind valve enabled reliable physical isolation between different petroleum products, ensuring a clearly verifiable disconnected state during media switching. This fundamentally eliminates the risk of internal leakage associated with conventional valves.

 

The drip-tight design effectively controlled evaporation and leakage when handling light hydrocarbons such as HSD, MA, and JET-A1, significantly improving on-site safety performance. In addition, the worm gear operation provided smoother and more controlled switching, reducing manual effort and minimizing the risk of operational errors, even in large-diameter applications.

 

Overall, the solution not only met the client’s stringent requirements for high sealing integrity and safety, but also improved the operational stability and maintenance reliability of the pipeline system.

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Dervos Valve Supply for Refinery in Hungary
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Project Background   In 2024, DervosValve was selected as a trusted valve supplier for a refinery project in Hungary. The client required large-sized industrial valves capable of handling complex and high-pressure oil and gas media. With years of engineering experience and proven track records in the energy sector, Dervos was chosen to provide a complete valve solution tailored to the refinery’s operational needs.     Scope of Supply   ● 10 pcs Gate Valves ● 9 pcs Check Valves   All valves were designed and manufactured according to API and ASME standards, ensuring compliance with international refinery safety and performance requirements.     Product Design & Technical Highlights   The supplied valves feature bolted bonnet design, flexible wedge, and rising stem with yoke support, which enhance sealing reliability and facilitate maintenance. Their large-scale structure was customized to fit the refinery’s pipeline system, allowing smooth fluid control and stable operation under high temperature and pressure.     Performance in Refinery Conditions   Refinery environments involve frequent temperature fluctuations and medium impurities. Dervos valves demonstrated outstanding sealing performance, corrosion resistance, and mechanical strength, ensuring long-term stability with minimal maintenance requirements. The bolted bonnet design also makes disassembly and inspection more convenient during scheduled shutdowns.   Why the Client Chose Dervos   The Hungarian client valued Dervos for: ● Proven experience in oil & gas valve solutions ● Strict material traceability and quality control system ● Flexible customization capabilities for large valve dimensions ● On-time delivery and complete documentation support   Throughout the project, our technical and logistics teams worked closely with the client’s engineers, ensuring each valve was tested, packaged, and delivered to meet project timelines and refinery installation standards.   Customer Feedback & Project Outcome   After installation and commissioning, the refinery reported stable operation and precise flow control performance. The valves’ large design and robust construction fully met system pressure and flow requirements. The client expressed satisfaction with both the quality and Dervos’ technical responsiveness, laying a solid foundation for future cooperation.   Conclusion   This successful refinery project in Hungary once again highlights Dervos’ ability to deliver reliable, large-size valve solutions for the oil and gas industry. We continue to serve our global partners with precision engineering, professional service, and long-term reliability.

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    If you are interested in our products and want to know more details,please leave a message here,we will reply you as soon as we can.

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