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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 ...

ball valve and check valve replacement
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DERVOS Valves Applied in MOL Refinery Upgrade Project in Hungarian

The refinery of MOL, located in Hungary, requires regular ball valve and check valve replacements to maintain optimal performance. As a trusted check and ball valve supplier of MOL, DERVOS continues to provide ball valves for their operations.

In this project, DERVOS supplied a batch of high-performance ball valves and check valves for fluid control in oil and gas applications. They required various types and specifications of ball and check to meet the operational and sealing requirements of different pipeline systems.

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Product Detail

DERVOS Valves Applied in MOL Refinery Upgrade Project in Hungarian


Trunnion Mounted Ball Valves (112 units)

· Size: DN80-DN400

· Pressure: PN16-PN63

· Features: Full flow ball valve design, DBB double block and bleed structure, PMSS seal (primary metal + secondary soft seal), anti-blowout stem, IP68 waterproof turbine operation. 


Floating Ball Valves (71 units) 

· Size: DN20-DN25

· Pressure: PN25-PN63

· Features: Floating ball design, handle operation, suitable for small and medium-sized pipelines.


Swing Check Valve (9 units) 

· Size: DN50-DN300

· Pressure: PN25-PN63

· Features: Swing type, simple structure and low flow resistance, suitable for large flow and low-velocity conditions.


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fixed ball valves were customized with 2-meter extended valve stems

Customized Solution


In this project, 4 units fixed ball valves were customized with 2-meter extended valve stems and turbines oriented toward the operating platform.


This design ensures operators can safely and efficiently operate and maintain the valves from a distance, fully addressing the site’s needs.


The custom solution showcases DERVOS’s flexibility in meeting customer requirements and engineering expertise.



Customer Feedback


The end user, MOL, highly recognized the quality and performance of the valves, noting the excellent painting for its durability. They praised DERVOS products as reliable, safe, and fully meeting the project’s requirements.


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Related Products
ECOFUEL Turns Waste into Diesel with DERVOS Valve Solutions
ECOFUEL Turns Waste into Diesel with DERVOS Valve Solutions

In 2017, DERVOS contributed to an innovative environmental initiative led by ECOFUEL, an emerging canadian player in clean technology. This groundbreaking project aimed to produce sustainable diesel from solid waste, setting a precedent in green energy solutions. DERVOS is proud to have provided 136 sets of premium valves to support this pioneering effort.

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.

Trunnion Mounted Ball Valve
API 6D Trunnion Ball Valve 8 Inch Class 300 WCB Gearbox

API 6D ball valve is designed with trunnion mounted ball and full bore structure. The flanged ball valve has 300LB design pressure and 8 inch nominal size with gearbox operation mode, conforming to NACE MR0175 requirement. Quick Detail Type Ball Valve Size 8” Pressure 300LB Construction Two-Piece Body, Full Bore, Trunnion Ball Connection RF Flange Operation Mode Gearbox Body Material A216 WCB Trim Material Ball/Stem F6a, Seat RPTFE Design & Manufacture API 6D Pressure & Temp Code ASME B16.34 End to End ASME B16.10 End Connection ASME B16.5 Inspection API 6D, API 598 Temperature Range -29℃~+200℃ Medium Oil, Water, Gas Dervos Packing Painting Test & Report Pressure Testing & Dimension Checking

Check Valve
DN250 PN10 Tilting Disc Check Valve RF WCB API598

DN250 PN10 check valve body is made of A216 WCB+STL. It has the structural characteristics of heavy hammer on both sides and flange type. Its connection mode is RF.

Plug Valve
2" 150LB Four Way Plug Valve API599 WCB RF Multi Way

2" 150LB plug valve is made according to API 599 standard. The valve body is made of A216 WCB. It has the structural characteristics of four way and bolt cover. Its connection mode is RF. And it has turbine operation mode.

Triple Eccenctric Butterfly Valve
14in 150LB Triple Eccentric Wafer Butterfly Valve Gearbox Soft Seal

WCB 14inch 150LB Butterfly Valve Triple Eccentric Un-directional Seal Wafer Type Gear Handwheel Operation WCB Body WCB Disc F6a Stem PTFE Seal Ring 13Cr Overlay on Seat. Design and Manufacture API 609. Face to Face Dimension API 609. Flange and Dimension ASME B16.5. Test and Inspection API 598. Quick Detail Type Butterfly Valve Size 14” Pressure 150LB Construction Triple Eccentric Connection Wafer Operation Mode Gearbox Body Material A216 WCB Trim Material Ball/Stem F6a, Seat PTFE Design & Manufacture API 609 Pressure & Temp Code ASME B16.34 End to End ASME B16.10 End Connection ASME B16.5 Inspection API 598 Temperature Range -29℃~+200℃ Medium Oil, Water, Gas

16 x 12 600LB Trunnion Mounted Ball Valve, Body A105, API6D
Pneumatic Actuator, 16" x 12" 600LB Trunnion Mounted Ball Valve, Body A105, API6D

16" x 12" 600LB trunnion mounted ball valve is made according to API6D standard. The valve body is made of A105. It has the structural characteristics of split type, side mounted, fixed ball, reduced diameter. Its connection mode is RF. And it has pneumatic operation mode.

4 Inch 150LB Cast Steel Swing Check Valve Body CF8M API 6D
4 Inch 150LB Cast Steel Swing Check Valve Body CF8M API 6D

4 Inch 150LB Cast Steel Swing Check Valve is made according to API 6D standard. The valve body is made of ASTM A351 CF8M. It has the structural characteristics of Swing Type, External Pin. Its connection mode is RF. 

Globe Valve
DN25 PN40 Forged Steel Globe Valve, EN1092-1 B Connection, Body F316, BS5352

DN25 PN40 forged steel globe valve is made according to BS 5352 standard. The valve body is made of A182-F316+STL. It has the structural characteristics of bolt cover and straight through type. Its connection mode is EN1092-1 B. And it has hand wheel operation mode.

Bellow Seal Globe Valve With Handwheel
Bellow Seal Globe Valve 1.5 Inch SW A105N OS&Y

The 1.5 inch 800LB bellow seal globe valve is designed with outside screw and yoke, handwheel operation, sw end. The reduced port globe valve is has forged steel A105N body. Design Feature 1.Outside screw and yoke 2.Rising stem 3.Bolted bonnet design 4.Bellow seal packing for reliable stem sealing 5.Reduced bore design 6.Handwheel Operated Quick Detail Type Globe Valve Size 1.5'' Design Pressure Class 800 Structure BB, OS&Y, Reduced Port, Bellow Seal Packing Connection Type Socket Weld Operation Handwheel Design Code API 602 End to End ASME B16.10 Connection End ASME B16.11 Pressure & Temperature ASME B16.34 Test & Inspection Standard API 598 Body Material Forged Steel ASTM A105 Trim Material Trim 8 Applicable Temperature -29℃~+425℃ Application W.O.G Origin China Related Knowledge What is a bellw seal valve? For bellow seal globe valves, the lower end bellows is welded on the valve stem to prevent the process fluid from eroding the valve stem. The other end is placed between the valve body and the valve cover to form a static seal. The double seal design ensure that if bellow seal pakcing fails, the stem packing will also function.  The bellow seal globe valves are applicable for media like steam, flammable, explosive, heat transfer oil, high purity, and toxic media etc. Special Tests Besides general tests we will do (hydraulic and air test), we could also do tensile strength test, metallographic test, fugitive emission test, and NDE test (UT,RT,PT,MT) upon customers’ specific requests.

Gate Valve
1" 800LB Forged Steel Gate Valve BW*NPT F5 API602

1" 800LB gate valve is made according to API 602 standard. The valve body is made of A182-F5. It has the structural characteristics of rigid gate, welded bonnet and extended valve body 100mm. Its connection mode is BW*NPT. And it has hand wheel operation mode.

RF Connection, 3 300LB Y Type Strainer, ASME B16.34,
RF Connection, 3" 300LB Y Type Strainer, ASME B16.34, Body A995 5A

3" 300LB Y type strainer is made according to ASME B16.34 standard. The valve body is made of ASTM A995 5A. It has the structural characteristics of Y-shaped, body cover bolted connection. Its connection mode is RF.

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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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