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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 ...

API609 PFA Lined Butterfly Valve LUG FF 20”150LB
加载中...

API609 PFA Lined Butterfly Valve LUG FF 20”150LB

This 20 inch butterfly valve is plastic lined type one. Its PFA lined disc and its PTFE seat ring enable it a excellent corrosion resistant performance. With a gearbox, it is easy to drive.

  • 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:

    Gearbox
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Product Detail

Quick Detail

Type

Butterfly Valve

Nominal Diameter

20'

Nominal Pressure

150LB

Construction

Flat Flange

Connection

Lug Type;

Operation

Gearbox

Design & Manufacture

API609

End to End Dimension

ASME B16.10

Flange Dimension

ASME B16.5

Body Material

A216 WCB

Disc Material

SS2205+PFA

Media

W.O.G


Features

--Substantial PFA liners for 3" through 12" and PTFE liners for 14" through 24"

Well resistance to permeation leading to extension of product life and operator safety

 

--Low torque. Smaller operators taking up less space, ease of operation and cost savings with less expensive automation packages.

 

--Improved disc design leads to less deflection at higher pressures and tighter in-line seal.


Technical Drawing



Painting Check


Packing


Our Main Product Range

As an experienced supplier and vendor of industrial valves, Dervos supply cast steel valve, forged steel valve, cast iron valve, stainless steel valve, bronze valve, brass valve and alloy steel valve and so on, suitable for sea water, water, oil, and gas application.


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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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The PTFE fully lined butterfly valve is made of cast iron body and with gearbox operation. The 14 inch flanged valve has concentric type structure. Quick Detail Type Butterfly Valve Size 14'' Design Pressure 150LB Construction Concentric Type, PTFE Lined Connection Type Double Flanged Operation Gear Operated Design Code API 609 Face to Face ASMEB16.10 End Connection ASMEB16.5 Test & Inspection API 598 Body Material Cast Iron GGG40 Temperature Range -15℃~+150℃ Application Water, Oil, Gas Related Knowledge What is the advantage of fully lined butterfly valve? The main advantage of lined butterfly valve is that it can handle abrasive and corrosive application at a relatively lower cost. The PTFE or PFA flexible seat provide a zero leakage sealing performance. Plus, the lined material PTFE has strong corrosion resistance, stable performance, low friction coefficient, which make the lined butterfly valve has a long service life. How does Dervos control quality of raw material? Raw material plays an important role in product quality. Likewise, casting and forging affect valve quality a lot. That is why Dervos pay a lot of attention to foundries. We have an approval list of foundries and classify them by certificates, scale, process and materials. To meet different requirements from customers, we could even appoint suitable foundries for our customers.

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Dervos Valve Supply for Refinery in Hungary
Dervos Valve Supply for Refinery in Hungary

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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    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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