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The Impact of Butterfly Valve Installation Orientation and Spatial Layout on Valve Performance
The Impact of Butterfly Valve Installation Orientation and Spatial Layout on Valve Performance
2025-08-01

The butterfly valve, as a compact, quick-opening, and low-resistance regulating valve, is widely used in industries such as water supply and drainage, HVAC, power, chemical, and paper-making. However, in practical engineering applications, improper consideration of the butterfly valve’s installation direction and spatial arrangement often leads to valve operating abnormalities, decreased sealing performance, and deviations in control accuracy. In severe cases, it can even cause system failures or frequent maintenance, resulting in unnecessary economic losses. Therefore, a correct understanding of the impact of installation orientation and spatial layout on butterfly valve performance is essential to ensure its reliable operation and extend its service life.     1. The Impact of Installation Orientation on Butterfly Valve Performance   (1) Fluid Flow Direction and Its Effect on Sealing Performance For centerline butterfly valves, where the valve disc rotates around the valve shaft, the force is relatively symmetric, and the fluid flow direction has little impact on the sealing performance. Therefore, the flow direction requirement is not strict during installation. However, for eccentric butterfly valves, especially double-eccentric and triple-eccentric types, the seal design is based on the "flow-assisted compression" principle. That is, when the medium pressure comes from the specified direction, it pushes the valve disc toward the sealing seat, thereby enhancing the sealing effect.   If the valve is installed in the opposite direction of the flow arrow marked by the manufacturer, the reverse fluid flow will wash the valve disc. Not only will the expected sealing effect not form, but it may also create gaps between the sealing surfaces, accelerate valve seat wear, and cause internal leakage, making it impossible to close the valve completely. Therefore, the installation of eccentric butterfly valves must strictly follow the flow direction requirements.   (2) Valve Shaft Orientation and Its Effect on Opening/Closing Torque and Actuator The installation orientation of the valve shaft (horizontal or vertical) has a significant impact on the opening/closing performance, valve body stress, and actuator life. Most medium and small-sized butterfly valves are installed with the valve shaft in the horizontal position. This method facilitates the alignment of the valve body with the pipeline and the arrangement of the actuator.   However, for large-diameter butterfly valves or those installed in high locations or vertical pipelines, the valve shaft is often vertical. In this position, the weight of the valve disc directly acts on the valve shaft, especially when the valve disc is in the open position, where its center of gravity deviates from the axis, creating a large eccentric torque and increasing the axial load during opening and closing. If the actuator does not account for this additional load, it may result in po...

Dervos Becomes YPFB's Qualified Valve Supplier
Dervos Becomes YPFB's Qualified Valve Supplier
2025-07-16

YPFB (Yacimientos Petrolíferos Fiscales Bolivianos) as Bolivia's state-owned oil and gas company, plays a critical role in the exploration, production, and distribution of oil and natural gas across Bolivia. It has a strong commitment to quality and innovation. DERVOS VALVE is honored to have passed the qualification review and become one of contract valve suppliers of YPFB.   • Supplier Qualification Requirements for YPFB Becoming a supplier for YPFB requires meeting several stringent qualifications. YPFB looks for suppliers with a proven track record of reliability, technical expertise, and product quality. This includes compliance with international industry standards and certifications,along with the ability to provide high-performance products that meet the specific needs of Bolivia’s oil and gas industry. The process also involves submitting detailed technical documentation, including certifications, safety records,and previous successful project references.   •  Application Process to Become a YPFB Supplier The application process to become a certified supplier for YPFB is highly competitive and rigorous. The first step is to submit an official application, followed by a review of the company’s credentials. Dervos Valve underwent this process and provided comprehensive technical documentation, including product specifications and compliance with safety standards. Our team also participated in interviews and site visits, showcasing our manufacturing capabilities and commitment to quality. DERVOS VALVE will supply a range of valves to YPFB for use in their oil and gas operations, including high-performance ball valves, gate valves, globe valves, and check valves. These products are crucial for ensuring the safety and efficiency of operations in challenging conditions.   Dedicated to consistent product quality through daily operations, we ensure excellence in performance. Our ongoing commitment is providing partners with professional support and premium services, fostering mutual growth and win-win success.  

Global Partners Reunite to Celebrate Dervos' 17th Anniversary Milestone
Global Partners Reunite to Celebrate Dervos' 17th Anniversary Milestone
2025-07-03

To mark this milestone in Dervos Valve’s journey, we came together not just to celebrate, but to connect with the partners who have supported us along the way. This anniversary is a tribute to enduring partnerships and a sha- red vision for the future.   On the occasion of Dervos Valve’s 17th anniversary, our valued partners were specially invited to visit our headquarters for in-depth, face-to-face exchanges with the team. These meaningful interactions deep- ened mutual understanding andtrust, laying a solid foundation for even stronger cooperation in the future.   Accompanied by our team, the clients toured the office area and were introduced to colleagues from various departments. The interactions were relaxed and friendly, creating a warm atmosphere that further strengthened mutual understanding. Following the tour, our sales team delivered a themed presentation on “Dervos 17th Anniversary,” offering the clients a comprehensive overview of the company's development journey, core strengths, and service philosophy. We also expres- sed our heartfelt gratitude and warm welcome to our valued partners. Through this session, the clients gained a deeper understanding of Dervos, enabling us to better tailor our services to their needs. They expressed strong appreciation for Dervos’ steady growth and thanked us for inviting them to be part of this meaningful celebration.   In front of the company’s cultural wall, clients took a moment to sign and leave messages, expressing their well wishes for Dervos. This moment not only reflected cultural recognition but also a genuine expression of the emotional bond and trust shared through our partnership.   Next, we arrived at the highlight of the anniversary celebration— the Dervos Valve 17th Anniversary Gala Dinner, a moment of gratitude and shared celebration. We arranged a visit to the "Yu Jian Minnan" Cultural Park for our clients, where they explored the ancient architectu- ral district and experienced the traditional art of rubbings, immersing themselves in the charm and craftsman- ship of Chinese culture.   In the evening, a red carpet was laid out in front of the hotel, where the Dervos team warmly welcomed guests, coming together with partners from around the world to witness this moment of honor. As the lights came on, the anniversary gala dinner officially began. The venue was decorated in a grand and festive style, with a warm and lively atmosphere. The event kicked off with a performance that blended both Eastern and Western cultures,featuring a lineup of classic foreign songs and traditional Chinese pieces, showcasing Dervos' open and inclusive brand spirit, with a global outlook. During the interactive games and lucky draw sessions, guests actively participated and enjoyed themselves, with laughter and joy filling the air. This lively atmosphere showcased the cohesion and energy of the Dervos team.   As the familiar melo...

1/2 Inch 800LB Plug Valve WCB NPT Wrench
加载中...

1/2 Inch 800LB Plug Valve WCB NPT Wrench

This 1/2 Inch plug valve is made of A216 WCB, according to API598.With little required maintenance and trouble-free operation, a high integrity bubble-tight seal is provided both in-line and to atmosphere.

  • Payment:

    30% when order confirmed, 70% before shipment
  • Product Origin:

    China
  • Color:

    Customization
  • Shipping Port:

    Shanghai, China
  • Lead Time:

    30~60 days Ex Works after order confirmation
  • Material:

    A216 WCB
  • Method of Operation:

    Wrench
Inquiry now
Product Detail

Quick Detail

Type

Plug Valve

Nominal Diameter

1/2 Inch

NominalPressure

800LB

Construction

Sleeve Type

Connection

NPT

Design & Manufacture

API599

Ends End Dimension

ASME B1.20.1

F to F Dimension

ASME B16.10

Pressure Test

API598

Body Material

A216 WCB

Plug Material

A315 CF8

Temp. Range

≤120°C

Media

Water, Oil, Gas, etc

 

Features

-Free of cavities

-Maintenance free – self lubricating

-Easy accessible adjustment of the plug, even with mounted actuator

-Bi-directional in-line bubble-tight seal independent of line pressure
-Multiple external bubble-tight seals independent of line pressure
-Positive flow direction indication

 

Technical Drawing


Witness Tests


Packing


DVS Purchasing System

 

Dervos purchasing system plays an important role in order follow up and supplier management.

 

What does our purchasing team do?

-Confirm production plan with the factory

-Follow up the order according to the production plan very closely

-Take every measure to initiate all related resources to solve the delay crisis

-Seek new suppliers and put them into our supplier pool by evaluating them onquality, equipment, certificates, price level, technical supports etc

-Do annual evaluation on current suppliers and eliminate those unqualified ones.

 

All these actions will make sure that clients’ order will be delivered on time and we can find most suitable products among qualified suppliers in an efficient way.


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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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Leave a message

    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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