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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...

Line Blind Valve
加载中...

1" - 60" Class 150 - 2500 Line Blind Valve ASME B16.34

Line blinds are utilized in pipeline systems when there is a need for either complete closure or unimpeded flow transition without a significant drop in pressure. The THD (Through-Hole Design) enables swift and seamless adjustments in position. The THD-slide variant boasts a multi-bolt configuration, making it easier to operate with reduced face-to-face dimensions. The inclusion of extra body bolts renders this style particularly well-suited for high-pressure applications.

  • 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
Inquiry now
Product Detail

Features

1. Swift Transition: Blinding can be performed safely in a matter of minutes, even by operators with minimal experience.

2. Economical Solution: Decreases maintenance hours, resulting in savings on labor costs.

3. Toolless Handling: The process is simplified with a hand-wheel operation, eliminating the need for tools to achieve full shut-off.

Standard Specifications

Size

1'' - 60'' (DN 25 to DN 1500)

Pressure Class

Class 150 - 2500 (PN 2.5 to PN 400)

Design & Manufacture code

ASME B16.34

Flange Standard

ASME B16.5

Material

Carbon Steel, Stainless Steel, Hastelloy, and Titanium

Actuation

Manual, Pneumatic Hydraulic and Electric

Technical Drawing

Adaptable Design

In addition to its conventional design, the THD-Slide is available in variations tailored for High-Temperature, Fire Safety, and Non-Drip applications. For installations constrained by limited space, a compact version can be provided as well.

Easy Seal Inspection

In this design, the seals are housed within the spectacle plate. This characteristic offers the advantage of convenient access for inspection and seal replacement. Assessing the condition of these seals can be performed external to the operational process, prior to any position changes, thereby ensuring the integrity of the seal's quality.

Cost Effectiveness

The THD-Slide features a straightforward and robust design engineered to deliver complete shutdown, extended operational lifespan, and cost-effective service with minimal maintenance requirements. The distinctive mechanism for opening and closing the THD-Slide enables a single individual to rapidly and safely blind pipelines without the need for any tools or equipment.

THD-Slide Cutout

Part Description

Part Description

Material

Handwheel

QT400-18

Stem

A182 F6A

Stem Nut

Alloy Copper

Body

A350 LF2

Seal Carrier

A350 LF2

Seals in plate

Viton

Spectade Plate

A350 LF2+ENP

Position Stop

A193 B7

Driving module

A350 LF2

Body stud/Nuts

A193 B7/A194 2H

Other materials and seal rings are available upon request

Options

●Hand Wheel Extensions

●Locking Device

●Limit Switches

●Drain/Vent ports

●Spectacle Plate Covers to Protect Seals

●Compact Design (integral tapped end flange)

●Rain/Dust Shield

●Torque Limiter

Operation of Standard

Mechanism Principle

In normal conditions, the blind valve's diversion hole is in contact with the pipeline, and the blind valve is in the open position. When maintenance is required, and the pipeline must be cut off, then loosen the stem of blind valve to move the flat end onto the pipeline, and make the blind valve turn to closed position from open position; tighten the stem and let the blind valve to perform sealing function and cut off the pipeline.

When the maintenance work is completed, loosen the stem and move the blind plate to the diversion hole and connected to the pipeline. The blind valve was turned to closed position from open one. Lock the stem, and seal it, the pipeline is now open, and the blind plate valve returns to the open position.

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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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