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Troubleshooting Guide for Valve Vibration and Noise
Troubleshooting Guide for Valve Vibration and Noise
2026-01-06

These symptoms typically indicate a mismatch in fluid conditions, valve selection, or system configuration. If left unaddressed over prolonged operation, they can accelerate valve wear and pose safety risks.   Based on field experience, this article outlines the common causes of valve vibration and noise and provides practical guidance for troubleshooting.   1. Basic Manifestations of Valve Vibration and Noise   Valve vibration usually appears as noticeable oscillations of the valve body, stem, or connected piping. Noise may present as humming, whistling, or banging sounds.   These phenomena often occur simultaneously and are primarily related to the following factors: ● Abnormal flow velocity or pressure differential ● Unstable internal forces within the valve ● Mismatch between actual operating conditions and valve design   2. Common Causes Analysis   1. Excessive Flow Velocity or Pressure Differential When the fluid passes through the throttling section of a valve at high speed, strong turbulence and pressure fluctuations are likely to occur, causing periodic impact on internal components. This issue is particularly pronounced when using standard globe valves or ball valves under regulating conditions.   Typical manifestations include: ● Noise increases as the valve opening decreases ● Vibration intensifies under high-pressure-drop conditions   2. Improper Valve Selection Incorrect valve selection is a common root cause of vibration, such as: ● Using on/off valves for prolonged throttling ● Oversized valve operating at small openings for extended periods ● Insufficient pressure rating or structural rigidity of the valve These conditions can cause unstable movement of the valve plug or ball, resulting in vibration and noise.   3. Loose or Worn Internal Components After long-term operation, the following issues are commonly observed: ● Wear of valve plugs or discs ● Increased clearance between the stem and guiding parts ● Loosened fasteners   Non-design clearances amplify fluid impact, leading to persistent noise. If vibration is accompanied by metallic knocking sounds, the condition of internal components should be checked as a priority.   4. Cavitation or Flashing In liquid service, cavitation or flashing occurs when local pressure drops below the saturation vapor pressure. Bubble collapse in high-pressure regions impacts internal components, often accompanied by noise and vibration.   Typical signs include: ● Sand- or gravel-like scraping sounds ● Rapid wear of internal components ● Significant pressure fluctuations   5. Insufficient Piping Support or System Resonance Some vibrations are not directly caused by the valve. When upstream or downstream piping lacks adequate support, or when the piping structure resonates near the fluid pulsation frequency, system resonance may occur, amplifying existing vibrations...

Fire Safe Ball Valves Explained When Do You Really Need One
Fire Safe Ball Valves Explained When Do You Really Need One
2025-12-29

In industrial piping systems, safety is always a top priority. A Fire Safe Ball Valve is a specialized type of ball valve designed to maintain sealing and prevent leakage under high temperatures or fire conditions. Although it looks similar to a standard ball valve, its structure and functionality are significantly different. This article provides a detailed analysis of the working principle, applicable scenarios, and selection guidelines for Fire Safe Ball Valves.   1. Introduction to Fire Safe Ball Valves   A Fire Safe Ball Valve is designed for fire or extreme high-temperature conditions. Its core feature is the ability to maintain metal-to-metal sealing contact between the ball and the seat even if the valve seats or sealing elements are damaged by high heat, thereby preventing leakage of the medium.   Features: ● High-Temperature Sealing Protection: Even if soft sealing materials melt or burn, the metal seal continues to function. ● Compliance with International Standards: Common standards include API 607 and ISO 10497. ● High Durability: Suitable for harsh operating conditions and flammable or explosive media.   Working Principle: At normal temperatures, the soft valve seat ensures zero leakage. When the temperature rises to the soft seal failure point, a spring or preloading mechanism pushes the ball against the metal seat, achieving metal-to-metal sealing and preventing medium leakage under high temperatures or fire conditions.   2. Applicable Scenarios for Fire Safe Ball Valves   ● Petrochemical and Natural Gas: In pipelines carrying flammable or explosive media, a Fire Safe Ball Valve can effectively prevent fire from spreading through the valve. ● High-Temperature Process Systems: In steam, hot oil, or high-temperature gas pipelines, even if soft sealing materials fail due to heat, the metal seal ensures system safety. ● High Safety Requirement Applications:   In facilities such as refineries, chemical plants, and offshore platforms where safety standards are strict, using Fire Safe Ball Valves helps reduce the risk of leakage.   3. Differences Between Fire Safe Ball Valves and Standard Ball Valves   ● Sealing Materials: Standard ball valves typically use PTFE or other flexible materials for sealing, which can fail at high temperatures. Fire Safe Ball Valves engage a metal-to-metal seal when the soft seal fails. ● Design Standards: Fire Safe Ball Valves must comply with fire test standards, such as API 607, whereas standard ball valves do not have this requirement. ● Applicable Operating Conditions: Fire Safe Ball Valves are mainly used for high-temperature, high-pressure, or flammable/explosive media. Standard ball valves are suitable for conventional low- to medium-pressure, ambient-temperature media.   4. Selection Recommendations   Based on Medium Characteristics: ● For flammable, explosive, or high-temperature media, Fire Safe ...

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...

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.

Forged Steel Floating Ball Valve
DN25 PN16 Forged Steel Floating Ball Valve Body ASTM ISO 17292

DN25 PN16 Forged Steel Floating Ball Valve is made according to ISO17292 standard. The valve body is made of ASTM-A105. It has the structural characteristics of Split Body, Floating Ball, Full Bore, Fire-safe, Anti-static, Blow-out Proof Stem. Its connection mode is RF . And it has hand wheel operation mode.

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.

3 piece ball valve gear operator A105 4 inch 150LB
3 piece ball valve gear operator A105 4 inch 150LB

The 4 inch 150LB ball valve is a 3-piece one with reduced port, A105 body, F6A stem, ball and seat. The The valve is made as per API6D and is tested under API 598.

Butterfly Valve
10" 150LB Concentric Butterfly Valve Lug GGG40 API609 Lever

10" 150LB butterfly valve is made according to API 609 standard. The valve body is made of GGG40. It has the structural characteristics of medium line type and lug type (threaded hole). Its connection mode is lug. And it has lever operation mode.

Cast Steel Gate Valve Class 600
16 Inch Flanged Gate Valve WCB Rising Stem API 600

The 16 inch cast steel gate valve with gearbox and 600LB RF flange is designed as per API 600. The bolted bonnet gate valve features in rising stem, resilient wedge and metal seat. Quick Detail Type Gate Valve Size 16" Pressure Class600 Construction Bolted Bonnet, Rising Stem, OS&Y, Flexible Wedge, Metal Seat Connection RF Flange Operation Gearbox Design Code API 600 Face to Face ASME B16.10 Flange End ASME B16.5 Pressure & Temp ASME B16.34 Test & Inspection API 598 Body Material A216 WCB TrimMaterial Trim 5 Temperature Range -29℃~+425℃ Medium Water, Oil and Gas Origin China Dimension & Material Class 600 NPS in 2 2 1/2 3 4 6 8 10 12 14 16 18 20 24 DN mm 50 65 80 100 150 200 250 300 350 400 450 500 600 L-L1 (RF-BW) in 11.5 13 14 17 22 26 31 33 35 39 43 47 55 mm 292 330 356 432 559 660 787 838 889 991 1092 1194 1397 L2 (RTJ) in 11.625 13.125 14.125 17.125 22.125 26.125 31.125 33.125 35.125 39.125 43.125 47.25 55.375 mm 295 333 359 435 562 664 791 841 892 994 1095 1200 1407 H (OPEN) in 18.625 21.75 23.375 28 1/16 38 3/16 44 3/16 52.375 59 13/16 68.125 72.25 90.125 98 13/16 119 mm 474 553 593 713 970 1122 1330 1519 1730 1835 2290 2510 3022 W in 9.875 9.875 11 13/16 13.75 19 11/16 22 1/16 28.375 24 24 24 24 30 30 mm 250 250 300 350 500 560 720 610* 610* 610* 610* 760* 760* WT (kg) RF 41 58 88 131 253 413 623 784 1288 1820 2150 2540 4080 BW 35 50 68 104 208 328 496 637 1120 1448 1828 2201 3360 *Manual gear operator is recommended No Part Name Carbon steel to ASTM Alloy steel to ASTM Stainless steel to ASTM WCB LCB WC6 WC9  C5 CF8 CF8M CF3 CF3M 1 Body A216 WCB A350 LCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M A351 CF3 A351 CF3M 2 Seat Ring A105 A350 LF2 A182 F11 A182 F22 A182 F5 A182 F304 A182 F316 A182 F304L A182 F316L 3 Wedge A216 WCB A350 LCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M A351 CF3 A351 CF3M 4 Stem A182 F6 A182 F6 A182 F304 A182 F304 A182 F316 A182 F304L A182 F316L 5 Bonnet nut A194 2H A194 4 A194 7 A194 8 6 Bonnet bolt A193 B7 A320 L7 A193 B16 A193 B8 7 Gasket SS Spiral Wound graphite or SS Spiral Wound PTFE 8 Bonnet A216 WCB A352 LCB A217 WC6 A217 WC9 A217 C5 A351 CF8 A351 CF8M A351 CF3 A351 CF3M 9 Backseat bushing A182 F6 A182 F6 A182 F304 A182 F304 A182 F316 A182 F304L A182 F316L 10 Stem packing Graphite or PTFE 11 Lantern A182 F6 A182 F6 A182 F304 A182 F304 A182 F304 A182 F304 A182 F316 A182 F304L A182 F316L 12 Gland Nut A194 2H A194 8 13 Gland Eyebolt A193 B7 A193 B8 14 PIN Carbon steel or Stainless Steel 15 Gland A182 F6 A182 F304 A182 F316 A182 F304L A182 F316L 16 Gland Flange A216 WCB A351 CF8 17 Stem Nut A439 D2 or B148-952A 18 Nipple Carbon steel or Stainless Steel 19 Retaining Nut Carbon steel 20 Hand Wheel Ductile Iron or carbon steel 21 Name Plate Stainless steel or Aluminum 22 H.W.Lock Nut Carbon steel

 Dual Plate Wafer Type Check Valve
12” 150LB Dual Plate Wafer Type Check Valve A995 4A API594

12” 150LB Dual Plate Wafer  Check Valve is made according to API594 standard. The valve body is made of A995 4A. It has the structural characteristics of Dual-plate, wafer type. Its connection mode is LUG RF. 

Gate Valve
2" 600LB Cast Steel Gate Valve RTJ WCB Hand Wheel API600

2" 600LB gate valve is made according to API 600 standard. The valve body is made of ASTM A216 WCB. It has the structural characteristics of rising stem, bracket, full bore and elastic wedge. Its connection mode is RTJ. And it has hand wheel operation mode.

 Y Type Strainer
2” 150LB Y Type Strainer RF ASTM ASME B16.34

2” 150LB Y Type Strainer is made according to ASME B16.34 standard. The valve body is made of ASTM A352 LCB. It has the structural characteristics of BB,OS&Y. Its connection mode is RF.

API 6D Trunnion Mounted Ball Valve
Cast Steel Trunnion Ball Valve 24 Inch 300LB API 6D

The Class 300 flanged ball valve has cast steel WCB body, stainless steel ball, stem, seat ring along with Devlon seat insert. We also supply more types of trunnion mounted ball valve, accept customized. Design Feature 1.Firesafe design as per API 607 2.With sealant injection for self lubricating 3.With antistatic design 4.With anti-blowout stem 5.With vent and drain port 6.Full bore design 7.Three-piece type and trunnion ball 8.Gear operated for easy operation Quick Detail Type Ball Valve Size 24" Pressure ANSI 300 Construction Trunnion Type Ball, 3-Piece Body, Side Entry, Full Bore Connection Flange Connection Operation Gearbox Operation Body Material ASTM A216 WCB Design Code API 6D Pressure & Temp Code ASME B16.34 Face to Face ASME B16.10 End Connection ASME B16.5 Test & Inspection Code API 598, API 6D Fire Safe API 607 Temperature Range -29℃~+200℃ Medium WOG Origin China Dimension CLASS 300 DN mm 50 65 80 100 150 200 250 300 350 400 450 500 600 700 NPS in 2 2.5 3 4 6 8 10 12 14 16 18 20 24 28 L (RF) mm 216 241 283 305 403 502 568 648 762 838 914 991 1143 1346 in 8.5 9.5 11.13 12 15.88 19.75 22.38 25.5 30 33 36 39 45 53 L1 (BW) mm 216 241 283 305 457 521 559 635 762 838 914 991 1143 1346 in 8.5 9.5 11.13 12 18 20.5 22 25 30 33 36 39 45 53 L2 (RTJ) mm 232 257 298 321 419 518 584 664 778 854 930 1010 1165 1372 in 9.13 10.13 11.75 12.63 16.5 20.38 23 26.13 30.63 33.63 36.63 39.75 45.89 54 H mm 153 165 195 213 272 342 495 580 625 720 790 840 1050 1150 in 6.02 6.5 7.68 8.39 10.7 13.5 19.5 22.85 24.6 28.35 31 33.1 41.34 45.3 Do(W) mm 400 400 600 850 1100 1500 *350 *350 *600 *600 *800 *800 *800 *800 in 15.74 15.74 23.62 33.46 43.3 59 13.8 13.8 23.6 23.6 31.5 31.5 31.5 31.5 RF(Kg)   18 27 47 80 118 200 365 530 740 1030 1320 1540 2600 3900 BW(Kg)   14 2 38 65 105 185 342 503 713 1000 1285 1498 2540 3825 *Worm Gear or Electric Actuator Operated Dervos Quality Checking System In Dervos, we control quality throughout the whole manufacturing process. Casting inspection: Though casting inspection, we can find out the problem of raw material, such as shoddy casting, unqualified wall thickness, chemical composition and so on, which ensure that you will not be cheated.   Machining Inspection: On the one hand, we could ensure machining accuracy through this process. On the other hand, we can find out machining mistake as early as possible, to win more time for repairing and remaking  Final Inspection:  Final inspection activities include document and QC record review, visual examination, dimension check, pressure test, painting and packing check. You don’t need to come and inspect in person and all the documents could be provided as proof.

Butterfly Valve
3" 300LB Double Eccentric Butterfly Valve WCB API609 Lug

3" 300LB butterfly valve is made according to API609 standard. The valve body is made of WCB. It has the structural characteristics of double eccentric and high performance. Its connection mode is lug.

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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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