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Why Are Many Customers Surprised When They Receive DERVOS Valves?
Why Are Many Customers Surprised When They Receive DERVOS Valves?
2025-12-18

In the export of industrial valves, packaging is often regarded as merely the final step before delivery. However, during actual transportation, packaging directly affects the overall condition of the valve during transit, handling, and even at the moment the customer unpacks it.   For industrial valves that must undergo long-distance transportation and multiple transshipments, packaging itself is an integral part of product quality. Based on extensive export experience, DERVOS has established a clear, stable, and repeatable valve packaging standard to ensure that valves are delivered to customers safely and in perfect condition.   1. Pre-Packaging Preparation and Product Verification   Before entering the packaging process, all valves undergo cleaning, inspection, and product information verification. This stage ensures that each valve is in a stable and fully controlled condition before packaging.   ● Remove oil and grease from the valve body surface ● Inspect flange sealing surfaces and the valve cavity to ensure no foreign matter is present ● Install and securely fix the nameplate to ensure product information is clear and identifiable   This process provides a reliable foundation for subsequent protection and transportation.   2. Internal Anti-Corrosion Treatment and Sealing Surface Protection   To address the conditions typically encountered during export transportation, valves receive targeted protective treatment prior to packaging:   ● The valve cavity is evenly coated with anti-rust oil to reduce the risk of corrosion in humid or salt-laden environments ● Protective covers are installed on all flange faces to prevent impact damage or contamination during handling and transport   These measures ensure that both internal components and sealing surfaces remain in good condition until the valves arrive at the customer's site.   3. Multi-Layer Inner Packaging and Individual Valve Protection   During the inner packaging stage, DERVOS applies a multi-layer cushioning structure to provide comprehensive protection for each valve:   ● Impact-resistant pearl cotton is placed around all sides and at the bottom of the inner carton ● Separators are installed between valves to prevent direct contact ● Each valve is individually wrapped with protective cushioning material, with special attention given to coatings and machined surfaces   This packaging structure effectively reduces the risk of paint damage, abrasion, and surface defects during transportation.   4. Custom Partition Fixing and User-Friendly Design   When multiple valves are packed in the same crate, custom wooden partitions are used to secure each unit:   ● Valves are precisely positioned according to their dimensions to prevent movement inside the crate ● Partitions feature chamfered edges, making it easier for customers to open the crate and remove the valves ●&nb...

What are the differences between globe valves and gate valves?
What are the differences between globe valves and gate valves?
2025-12-12

In industrial piping systems, globe valves and gate valves are two of the most commonly used shutdown valves. Although both are designed for starting and stopping fluid flow, they differ significantly in structural design, operating principles, application scenarios, and overall performance. Understanding these differences helps engineers make informed selections that ensure system efficiency, reliability, and cost-effectiveness.   I. Key Differences in Structure and Operating Principles   1. Different opening and closing mechanisms Globe Valve: The disc moves up and down along a path perpendicular to the flow direction. Shutoff is achieved when the disc and seat sealing surfaces come into full contact. Gate Valve: The gate moves vertically in a manner similar to a “gate” that is either fully open or fully closed, with sealing achieved through surface compression.  This means that globe valves are suitable for precise throttling, while gate valves are mainly used for full open or full shut service.   2. Flow path design differences A globe valve has an S-shaped flow path that forces the medium to change direction, resulting in higher flow resistance. A gate valve features a straight-through flow path with minimal resistance and low pressure drop, making it better suited for long-distance transmission.   II. Differences in Application Scenarios   1. Throttling vs. On/Off Service Globe valves can be used for throttling and flow regulation, making them suitable for applications requiring high sealing performance and precise flow control, such as steam, cooling water, and various process media.   Gate valves are not suitable for throttling, as operating them in a partially open position may cause gate vibration, damage to the sealing surfaces, and fluid-induced impact. Gate valves are ideal for large-diameter pipelines where low flow resistance is required and switching frequency is relatively low, including oil transportation, water supply and drainage, and power plant systems.   2. Size range and installation space Globe valves are generally used in small to medium sizes (more common below DN50). Their body structure is heavier and requires more installation space. Gate valves are suitable for medium to large sizes. Due to their simpler design, they offer a cost advantage in larger dimensions.   III. Sealing Performance and Pressure Ratings   1. Differences in sealing surface design The globe valve features a tapered sealing surface, which achieves tight shutoff through axial compression, making it easier to obtain reliable sealing performance. The gate valve uses either parallel or wedge-type sealing surfaces. Its sealing effectiveness depends largely on the pressure applied by the gate and is more influenced by the system’s medium pressure.   2. Pressure and temperature adaptability Both valve types are suitable for medium- to high-pressure and high-temperature applications....

Key International Standards for Butterfly Valves: Detailed Overview of API 609, ISO 5752, and JB/T 8527
Key International Standards for Butterfly Valves: Detailed Overview of API 609, ISO 5752, and JB/T 8527
2025-12-05

Butterfly valves are widely used in industrial piping systems due to their compact structure, lightweight design, and quick operation. They are commonly applied in water treatment, chemical, power, oil, and gas industries. However, when dealing with industrial standards across different countries and regions, selecting a butterfly valve that meets the relevant specifications is crucial. This article provides a detailed analysis of butterfly valve design and selection requirements based on three key standards: API 609, ISO 5752, and GB/T 12238.   1. API 609 — American Petroleum Institute Standard   API 609 is the American Petroleum Institute (API) standard for metal-seated butterfly valves, primarily used in the oil, gas, and chemical industries. The standard defines valve structure, materials, dimensions, and pressure ratings to ensure reliable performance under high temperature, high pressure, and corrosive media conditions.   Key points include: ● Pressure Ratings: Covers Class 150 to 1500, accommodating various service conditions. ● Body and Disc Design: Metal-to-metal sealing requires precise alignment between disc and seat to prevent leakage under high temperature or high pressure. ● Testing and Inspection: Includes shell tests, seat leakage tests, and operational performance checks to ensure valve safety and reliability.   For high-temperature steam or high-pressure oil and gas pipelines, selecting a butterfly valve compliant with API 609 can significantly reduce leakage risk and extend equipment lifespan.   2. ISO 5752 — International Standard Organization Standard   ISO 5752 is the International Organization for Standardization (ISO) standard that specifies end dimensions and flange connection sizes for valves. It defines the face-to-face dimensions, flange sizes, and connection methods for butterfly valves, providing a consistent interface specification for industrial users worldwide.   Key points include: ● Face-to-Face Dimensions: Specifies valve lengths for different nominal diameters to ensure compatibility with piping systems. ● Flange Dimensions: Ensures valves match international standard pipe fittings, such as ANSI or DIN flanges. ● Interchangeability: Butterfly valves designed according to ISO 5752 can be replaced or serviced globally without redesigning the pipeline interface.   ISO 5752 is particularly suitable for multinational engineering projects, ensuring the universality of butterfly valves across different plants and systems.   3. JB/T8527 — Chinese National Standard   JB/T8527 is the Chinese national standard specifying the dimensions, structure, and testing requirements for metal hard-seal butterfly valves. It is widely applied in domestic industrial projects such as water conservancy, power, and petrochemical industries, serving as an important reference for procurement and acceptance.   Key ...

Gate Valve
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API 6D Through Conduit Gate Valve Soft Seated 20 Inch 600LB

The API 6D through conduit gate valve is designed with 600 LB flange and gearbox connection. Made of carbon steel WCB, the 20 inch gate valve has soft seat design without diversion hole.

  • 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 A216 WCB
Inquiry now
Product Detail

Product Description

Type

Through Conduit Gate Valve

Size

20 Inch

Pressure

Class 600

Construction

Through Conduit, Soft Seated, Without Diversion Hole

Connection

RF Flange, Butt Weld

Operation

Gearbox

Body Material

ASTM A216 WCB

Design Code

API 6D

Pressure & Temp Code

ANSI B16.34

Test & Inspection Code

API 598

Medium

Water, Oil and Gas

Origin

China

Product Range

Body material: Carbon Steel, Stainless Steel, Alloy Steel

Normal diameter: 2’’ ~ 60’’ (DN50 ~ DN1500)

End connection: Butt Weld, Flange

Pressure range: 150lbs ~ 2500lbs (PN16 ~ PN420)

Operation: Handwheel, Gearbox, Electric, Pneumatic, Electro Hydraulic Actuator, Gas over oil actuator

Working temperature: -46℃~ +200℃

Seat Type: Meta to Metal Seat, Soft Seat

Material

Part Name

Material

Body & Bonnet

A216 WCB,CF8,CF8M,CF3,CF3M

Wedge

Alloy Steel(face harden treated), Stainless steel(with Co overlay)

Stem

Alloy steel(face erosion-resistant treated)

Seat

Alloy Steel(race Harden Treated,Beset F plastic),Steel(with Co overlay,Beset F plastic)

Packing

PTFE

O-Ring

NBR,FEP

 Dimension

About Dervos

Xiamen Dervos Valve Industry Co.,Ltd was founded in 2008. We are an doer at valve industry and accumulated ten years export experiences. Dervos alway focus on customer's feeling. We pay attention to what our customer paid. 

This kind of faith help Dervos people developing continuously.

Our Main Product Range

Our Valve products include Ball Valves, Butterfly Valves, Check Valves, Gate Valves, Globe Valves, and Plug Valves in various different materials, sizes, standards and types.

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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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Project Background   In 2024, DervosValve was selected as a trusted valve supplier for a refinery project in Hungary. The client required large-sized industrial valves capable of handling complex and high-pressure oil and gas media. With years of engineering experience and proven track records in the energy sector, Dervos was chosen to provide a complete valve solution tailored to the refinery’s operational needs.     Scope of Supply   ● 10 pcs Gate Valves ● 9 pcs Check Valves   All valves were designed and manufactured according to API and ASME standards, ensuring compliance with international refinery safety and performance requirements.     Product Design & Technical Highlights   The supplied valves feature bolted bonnet design, flexible wedge, and rising stem with yoke support, which enhance sealing reliability and facilitate maintenance. Their large-scale structure was customized to fit the refinery’s pipeline system, allowing smooth fluid control and stable operation under high temperature and pressure.     Performance in Refinery Conditions   Refinery environments involve frequent temperature fluctuations and medium impurities. Dervos valves demonstrated outstanding sealing performance, corrosion resistance, and mechanical strength, ensuring long-term stability with minimal maintenance requirements. The bolted bonnet design also makes disassembly and inspection more convenient during scheduled shutdowns.   Why the Client Chose Dervos   The Hungarian client valued Dervos for: ● Proven experience in oil & gas valve solutions ● Strict material traceability and quality control system ● Flexible customization capabilities for large valve dimensions ● On-time delivery and complete documentation support   Throughout the project, our technical and logistics teams worked closely with the client’s engineers, ensuring each valve was tested, packaged, and delivered to meet project timelines and refinery installation standards.   Customer Feedback & Project Outcome   After installation and commissioning, the refinery reported stable operation and precise flow control performance. The valves’ large design and robust construction fully met system pressure and flow requirements. The client expressed satisfaction with both the quality and Dervos’ technical responsiveness, laying a solid foundation for future cooperation.   Conclusion   This successful refinery project in Hungary once again highlights Dervos’ ability to deliver reliable, large-size valve solutions for the oil and gas industry. We continue to serve our global partners with precision engineering, professional service, and long-term reliability.

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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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