Pressure Sealing Globe Valves: An In - Depth Overview

Product Overview

Self-Sealing Globe Valves are designed for precise flow control and shut-off applications in high-pressure systems.Their self-sealing mechanism ensures reliable operation under extreme conditions without requiring additional tightening. Constructed from forged steel, these valves provide excellent durability and performance in challenging environments,making them ideal for critical industrial processes.

Self-Sealing Globe Valve Specifications

Design points of self-sealing stop valve

The design of a self-sealing stop valve (a type of globe valve that uses pressure-assisted sealing) is optimized for high-pressure, high-temperature environments. The following are key design points for a self-sealing stop valve:

1. Pressure Seal Bonnet:

Self-Sealing Mechanism: The valve bonnet is designed to use the system's internal pressure to create a tighter seal. As the pressure increases, the bonnet is forced down against the body of the valve, enhancing the seal without relying on external forces.

Pressure Gasket: The bonnet typically incorporates a pressure gasket, which compresses and seals better as the internal pressure rises. This design eliminates the need for bolted joints, reducing the risk of gasket failure.

2. Body and Bonnet Materials:

Forged Steel or Alloy: The valve body and bonnet are typically constructed from forged steel, high-grade alloys, or other materials that can withstand high pressures and temperatures. These materials are selected for their strength, corrosion resistance, and thermal expansion properties.

High-Temperature Resistance: The valve materials should be able to withstand thermal cycling, especially in applications like steam systems, without deforming or failing.

3. Disc and Seat Design:

Tight Shutoff: The disc (or plug) is designed to create a tight shutoff when it contacts the seat, preventing leakage when the valve is closed. The seat is often hard-faced with wear-resistant materials like Stellite to ensure durability under severe conditions.

Guided Disc: A guided disc ensures proper alignment with the seat, reducing wear and enhancing the valve's sealing performance. This design also helps with smooth operation and extends the valve’s lifespan.

4. Stem Design:

Non-Rising Stem: Most self-sealing stop valves feature a non-rising stem design, which keeps the stem from moving up and down outside the valve body. This saves space in tight installations and reduces the risk of stem damage.

Threaded Stem: The stem is typically threaded and connected to the disc. It operates by rotating, which moves the disc up or down to open or close the valve. The threads are usually fine to ensure precise control over flow.

5. Sealing Surfaces:

Hardfacing: The sealing surfaces (seat and disc) are often hard-faced with materials like Stellite or cobalt-based alloys, which are highly resistant to wear and corrosion, ensuring long service life in high-pressure conditions.

Lapped Finish: The sealing surfaces are typically lapped to ensure a smooth, tight seal between the disc and the seat, minimizing leakage and maximizing efficiency.

6. Bolting and Flanges:

Self-Sealing Bonnet: A key design point is the elimination of external bolting for the pressure boundary in the bonnet. Instead, the internal pressure forces the bonnet against the body, achieving a tight seal. This reduces the need for external bolting, enhancing reliability in high-pressure environments.

Flanged or Welded Ends: Depending on the application, the valve may have flanged or welded ends to connect it to the pipeline. Welded ends provide a permanent, leak-proof connection for high-pressure services.

7. Flow Characteristics:

Flow Control: The globe valve design offers precise throttling control. The linear motion of the disc allows for fine adjustment of the flow, making it ideal for applications requiring flow regulation.

Flow Resistance: Although globe valves inherently offer more flow resistance compared to other types (like gate valves), their design ensures controlled flow in stop applications where precise control is more important than minimal resistance.

8. Thermal Expansion Considerations:

Stress Management: High-pressure and high-temperature systems often experience significant thermal expansion. The valve design must account for these stresses to prevent warping or cracking. Material selection and component thicknesses are critical to ensuring that the valve can handle the expansion and contraction cycles.

Bonnet Flexibility: Some designs include flexible bonnet components to compensate for thermal expansion and maintain sealing integrity during temperature fluctuations.

9. Operation and Maintenance:

Manual or Actuated Operation: Self-sealing stop valves can be manually operated or fitted with actuators for remote operation, especially in automated systems where safety and precision are critical.

Maintenance Access: The design should allow easy access to the bonnet, stem, and disc for maintenance or replacement without dismantling the entire valve from the pipeline. This is often achieved with a bolted cover over the self-sealing area.

10. Safety Features:

Pressure Relief: High-pressure systems may require pressure relief or bypass systems to prevent over-pressurization, and the valve design should incorporate these elements for enhanced safety.

Blowout Prevention: The stem and disc should be designed to prevent blowout under high pressure. This typically involves securing the stem with additional components like a backseat or locking mechanism to ensure it stays in place under all operating conditions.

The main advantages of a self-sealing globe valve

1.Tight closure: They provide a reliable seal against leakage in both directions when fully closed.

2.Versatility: They can be used for a wide range of applications, from low to high pressure and temperature conditions.

3.Easy maintenance: These valves are relatively easy to maintain and repair due to their simple design.

4.Precise control: They allow for fine control of flow due to the linear motion of the disc against the seat.

5.Quick operation: The globe valve can be opened or closed quickly, which is beneficial in emergency shutdown situations.

6.High pressure drop: They are suitable for applications where a significant pressure drop is required to control the flow.

7.Availability in various materials: They are available in a range of materials to suit different fluid and environmental conditions.

Industrial Globe valves Applications

Self-Sealing Globe Valves are ideal for:

High-pressure steam systems

Oil and gas pipelines

Chemical processing plants

Power generation systems

Industrial fluid control processes

These valves are essential for industries requiring precision flow control and exceptional durability in critical operations.

Introducing our PSB OS&Y Globe Valve,designed for high performance and reliability in fluid control applications.This globe valve is a critical component for effectively shutting off or regulating flow within pipelines, and our PSB OS&Y Globe Valve is engineered to exceed industry standards. Constructed with durable materials and precision engineering, this globe valve is designed to withstand high temperatures and pressure levels, making it ideal for a wide range of industrial and commercial settings. The outside screw and yoke (OS&Y) design of this valve ensures smooth operation and easy maintenance, while providing added protection against leakage and corrosion. 

Our PSB OS&Y Globe Valve is available in a variety of sizes and pressure ratings, providing flexibility to meet the specific requirements of any project. Whether it’s for water treatment, chemical processing, oil and gas, or other applications, our globe valve is built to deliver reliable and long-lasting performance. At our company, we take pride in delivering quality products that meet the highest standards of safety and performance. With our PSB OS&Y Globe Valve, you can have confidence in the integrity of your fluid control system. Contact us today to learn more about how our globe valve can enhance the efficiency and reliability of your operations.