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Unite Strength, Create the Future Together --Dervos Annual Grand Event Successfully Concluded
Unite Strength, Create the Future Together --Dervos Annual Grand Event Successfully Concluded
2026-03-02

This year’s Dervos annual conference was noticeably more grand and well-organized than in previous years.   In the morning session, each department delivered its annual work summary, reviewing key projects and achievements over the past year. Teams also openly shared the challenges encountered during implementation and the practical experience gained along the way.   Through this cross-department exchange, everyone developed a clearer understanding of one another’s responsibilities and workflows, laying a stronger foundation for future collaboration and communication.     In the afternoon session, the Outstanding Employee awards were presented. Each nominee shared their work achievements and practical experience, demonstrating a strong sense of responsibility and execution across different roles. It is precisely this proactive mindset, collaborative spirit, and down-to-earth working approach of Dervos employees that drives the team steadily toward its shared goals.     Showing up on time every single day throughout the year — that’s quite an achievement. Ian has now received the Perfect Attendance Award for two consecutive years.     During the annual conference, Dervos also presented medals and exclusive commemorative gifts to employees who have completed five years of service.     Dervos values the long-term dedication and consistent commitment of its team members, and sincerely appreciates the trust and contributions they have made over the years. For many at Dervos, the company is not only a platform for professional growth, but also a stage where shared goals and collective efforts come to life. In the evening, the annual conference transitioned into the banquet segment. Performances and interactive games were seamlessly interspersed, creating a relaxed yet organized atmosphere.     Laughter and cheers echoed throughout the venue, and in the moment the camera shutter clicked, the excitement and joy were captured in a single frame.     Eric said: "Let’s dream together, DERVOS's dream. A dream where we all play a part, piece by piece, it becomes a reality." For Dervos, the annual meeting is not just about "summarizing the year," but about bringing our hearts together, strengthening our resolve in doing the same thing, and then continuing to move forward, step by step, with steady progress.            

What Is the Difference Between Plug Valves and Ball Valves?
What Is the Difference Between Plug Valves and Ball Valves?
2026-02-20

Ball valves and plug valves differ significantly in several aspects, including structure, operating principle, mode of operation, flow control capability, sealing performance, and application scenarios. These differences enable the two types of valves to perform distinct roles in their respective fields.   Structural Differences   The ball valve, a design evolved from the plug valve, utilizes a spherical element as its core component. By rotating the ball 90° around the stem axis, the valve can be opened or closed. Its structure is straightforward, consisting primarily of a spherical closure element with a through-bore housed within the valve body.   In contrast, the structure of a plug valve is more complex. It comprises multiple components such as the valve body, bonnet, plug, seat, and stem. The closure element is a cylindrical or tapered plug that controls flow by rotating 90°, aligning or misaligning the port in the plug with the flow passage in the valve body to achieve opening or shutoff.   Operating Principle   The operating principle of a ball valve relies on the rotation of the ball to control the on-off flow of fluid. When the ball is in tight contact with the valve seat, the clearance between them is completely sealed, thereby preventing fluid leakage. When the ball rotates to a position disengaged from the seat, the fluid is allowed to flow freely through the passage inside the valve body.   The operating principle of a plug valve differs in that it primarily controls the flow passage by rotating the plug element to open or close the valve. In a plug valve, the plug is connected to the stem and rotates together with it to achieve flow control. The closure element is a tapered plug with a port, and the flow passage is designed to be perpendicular to the axis of the plug. This configuration enables the plug valve to operate more efficiently and reliably during opening and closing.   The operation of a ball valve is notably simple, requiring only a 90-degree rotation to achieve opening or closing. This design allows the flow passage to be opened or shut off quickly and smoothly when the ball is rotated by 90 degrees, providing both convenience and efficiency. In addition, ball valves offer relatively low flow resistance in the fully open or fully closed position, making them particularly suitable for applications that require rapid on-off operation.   By contrast, the operation of a plug valve is comparatively more complex, as several turns are typically required to complete the opening or closing action. The valve plug is designed in a cylindrical or tapered form and regulates fluid flow through rotation. Nevertheless, plug valves demonstrate excellent performance in flow regulation, enabling precise adjustment of the flow passage diameter and accurate control of flow rate. However, due to the relatively complicated operating process, plug valves are not well suited for frequent operation...

Blind Plate Valve
Blind Plate Valve
2026-02-11

In industrial valve systems, a high-quality blind plate valve ensures safe and efficient operation of equipment. It is suitable for gas pipelines in metallurgy, chemical processing, petroleum, and municipal systems, serving as an effective device for positive gas isolation.   Working Principle and Features The blind plate valve consists of left, center, and right valve bodies, a valve plate, shafts, a compensator, and two drive units (for clamping and travel respectively). The clamping mechanism uses a drive assembly to actuate a linkage system, enabling three lead screws to operate synchronously and press the valve bodies against the valve plate to achieve sealing. This design provides good synchronization and uniform sealing force distribution. Positioning rollers are installed along the outer lower edge of the valve plate to enhance sealing reliability and ensure overall stability and sealing accuracy during operation, thereby extending the service life of the valve.   Valve Operating Sequence The clamping drive unit actuates the crank and linkage mechanism, causing the lead screws to rotate synchronously and retract the center body from the sealing surfaces (release condition). Guide wheels installed on the center body move laterally and simultaneously drive the valve plate. When the valve bodies are fully opened, the valve plate is positioned between the sealing faces of the left and right bodies, and the sealing surfaces are completely disengaged. The plate drive unit is then activated. Through a lever arm mechanism, the valve plate rotates, bringing the blind plate into the pipeline position. The clamping drive unit is started again to fully clamp the valve plate, completing valve closure.   Valve Opening The clamping drive unit first fully releases the valve bodies. The turning drive unit then rotates the valve plate so that the through-port aligns with the pipeline. Finally, the clamping electric actuator presses the valve plate to complete the opening operation.

LF2 Cryogenic Ball Valve
加载中...

Extended Stem Cryogenic Ball Valve LF2 1500LB BW

  • Payment:

    30% T/T When Order, 70% T/T Before Shipment
  • Product Origin:

    China
  • Shipping Port:

    Shanghai China
  • Lead Time:

    35~60 days Ex Works After Order Confirmation
  • Material:

    Low Temperature Steel Ball Valve, A350 LF2
  • Method of Operation:

    Gearbox Operated Ball Valve
Inquiry now
Product Detail

The Class 1500 4'' cryogenic ball valve is designed with extended stem for low temperature application. The valve is made of LF2 with fully welded body, butt weld end and gearbox operation. 

 

Design Feature
-Fully welded & forged body
-Extended stem or bonnet
-Full port design and piggable
-Anti blow-out stem
-Antistatic function
- Automatic cavity relief
-Bi-directional seat and DBB design
-With stem and seat grease fittings

 

Quick Detail

Type

Ball Valve

Size

4"

Pressure

ANSI 1500

Construction

One-Piece Body, Fully Weld, Extended Stem or Bonnet, Full Port

Connection

Butt Weld

Operation

Gearbox Operated

Body Material

Low Temperature Steel A350 LF2

Design Code

API 6D

Pressure & Temp

ASME B16.34

End to End Dimension

ASME B16.10

End Connection

ASME B16.25

Inspection

API 598

Temperature Range

-46℃~+200℃

Media

Oil, Water, Gas

 

Related Knowledge
What is the difference between full bore and reduced bore ball valve?

The internal diameter of a full bore ball valve is the same as the inner diameter of the pipe. The full bore ball valve has little resistance and pressure drop to the flow. Plus, the full bore ball valve is piggable.

However, the internal diameter of a reduced port (standard port) ball valve is smaller than the inner pipe size. Flow restriction caused by the reduced port will cause a pressure drop. And sometimes a pig to clean the pipe will get stuck in the reduced port ball valve.

 

 

 

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