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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...

Top Entry Ball Valve ASTM A105 8'' 900LB
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Top Entry Ball Valve ASTM A105 8'' 900LB

The 8 inch top entry ball valve with features of cavity pressure self-relief and emergency sealant injection is designed as per API 6D. It’s capable to handle working pressure up to 900LB.

  • 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:

    ASTM A105.
  • Method of Operation:

    Bare Stem
Inquiry now
Product Detail

Quick Details

Type

Ball Valve

Nominal Diameter

2"~60" (DN50~DN1500).

NominalPressure

150 lbs~2500 lbs (PN16~PN420).

Construction

Top Entry,One Piece Type

Connection

BW,RTJ

Operation

Gearbox, Electric, Pneumatic, Elector Hydraulic Actuator, Gas Over Oil Actuator.

Body Material

ASTM A105.

Design Code

API 6D.

Pressure & Temp

ASME B16.34

End toEnd Dimension

ASME B16.10

Inspection

API598

Temperature Range

-46℃~+200℃.

Media

Oil, Water, Gas


Dervos top entry ball valves are engineered to meet international standards of API 6D, ASME B16.34 and others on request. The range contains both soft , metal or composite seats that can be configured to provide an effective double block and bleed (DB&B) .


Features

·Soft, metal or composite material seated

·Bi-directional tight shut-off

·Double block & bleed

·Fire safe and fire tested

·Low operating torque design

·Wide range of materials and sizes

·Anti-blowout stem design

·Suitable for above ground or below ground installation

·Top-entry design enable maintenance in line

·Forged or cast body optional

·Extended Bonnet


Reports

Along with each order, Dervos will provide inspection reports and material test reports free of charge after shipment. All these certificates will let you have a clear picture of inspection process and results. Plus, these reports can be used for traceability. 


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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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