English

English

Get a Quote
Products

Hot Products

Company News

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...

DN200 PN16 Bellow Seal Globe Valve, RF, Body 1.4408
加载中...

DN200 PN16 Bellow Seal Globe Valve, RF, Body 1.4408, EN13709

DN200 PN16 Bellow Seal Globe valve is made according to BS EN 13709 standard. The valve body is made of EN 10213 1.4408. It has the structural characteristics of body cover bolt, rising pole bracket, angle type, corrugated pipe seal and structural length of 255mm. Its connection mode is RF. And it has hand wheel operation mode.

  • 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:

    EN 10213 1.4408
  • Method of Operation:

    Hand Wheel
Inquiry now
Product Detail

Product Description

 

Type

Bellow Seal Globe Valve

Size

DN200

Pressure

PN16

Connection

RF

Operation

Hand Wheel

Body Material

EN 10213 1.4408

Design Norm

BS EN 13709

Face to Face Dimensions

Client's Std.

Flange Ends Dimensions

BS EN 1092-1 B1

Test & Inspection Code

BS EN 12266

Applicable Medium

Water, Oil and Gas

Features

1. Adopting a double seal of corrugated tube and packing to prevent medium leakage and ensure zero leakage;

2. Built in guiding structure to avoid excessive expansion and contraction of the corrugated pipe, extending its service life.

Technical Drawing

DN200 PN16 Bellow Seal Globe Valve, RF, Body 1.4408, EN13709

Dimension Checking

DN200 PN16 Bellow Seal Globe Valve, RF, Body 1.4408, EN13709

Pressure Testing

DN200 PN16 Bellow Seal Globe Valve, RF, Body 1.4408, EN13709

Nameplate & Packing

DN200 PN16 Bellow Seal Globe Valve, RF, Body 1.4408, EN13709

Inspection report

DN200 PN16 Bellow Seal Globe Valve, RF, Body 1.4408, EN13709

DN200 PN16 Bellow Seal Globe Valve, RF, Body 1.4408, EN13709

DN200 PN16 Bellow Seal Globe Valve, RF, Body 1.4408, EN13709

DN200 PN16 Bellow Seal Globe Valve, RF, Body 1.4408, EN13709

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.

Related Products
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.

Bellow Seal Globe Valve PN40
Cast Steel Bellow Seal Globe Valve DN65 PN40 1.0619

Dervos bellow seal globe valve is designed as per EN13709 with face to face dimesnsion per EN558. The special designed bellow seal make sure zero leakage from stem. Quick Detail Type Globe Valve Norminal Size DN 65 NorminalPressure PN 40 Construction Bolted Bonnet, Rising Stem, Bellow Sealed ConnectionType RF Flange Operation Handwheel Design Code EN13709 Face to Face EN 558 Connection EN1092 Test & Inspection EN12266 Body Material Carbon Steel 1.0619 Bellow Material SS304, SS316, SS316L and etc ApplicableTemp -29℃~+420℃ Application Water, Oil, Gas Structure Feature 1. Standard design of double-wall bellow seal 2. Heat-dissipating bonnet design; 3. With lubricant storage device; 4, With design of circlip to fix stem nut; 5. Reasonable product structure, reliable sealing performance and good appearance; 6. The sealing surface is welded with Co-based hard alloy, which has good wear resistance, corrosion resistance, anti-friction performance and long service life; 7. Stem has nitriding treatment with good corrosion resistance and anti-friction performance; 8. With position indicator for stem movement;

Globe Valv
Bellow Seal Globe Valve 1.5 Inch 150LB Forged Steel

The bellows seal globe valve adopts the bellows seal design, which completely eliminates the shortcomings of the normal valve stem packing seal aging and easy to leak, not only improves the energy efficiency, increases the safety of the production equipment, reduces the maintenance cost and frequent maintenance. It also provides a clean and safe working environment.Its simple structure and the low price makes it almost no "competitors".  Quick Detail Type Globe Valve Norminal Size 1.5 Inch NorminalPressure 150LB Construction Bolted Bonnet, Outside Screw & Yoke, Rising Stem, Bellow Seal ConnectionType RF Flange Operation Handwheel Design Code ASME B16.34, API 602 Face to Face ASME B16.10 Flange End ASME B16.5 Test & Inspection API 598 Body Material ASTM A105 ApplicableTemp -29℃~+425℃ Application Water, Oil, Gas Structure Feature 1. Double seal design (corrugated pipe + packing). If the bellows fails, the stem packing will also be avoided; 2. External leakage, and in line with international sealing standards; 3. No fluid loss, reduce energy loss, and improve plant equipment safety; 4. Long service life, reduce the number of maintenance, reduce operating costs; 5. Rugged bellows seal design, ensuring zero leakage of the valve stem, providing maintenance-free conditions. Technical Drawing Dimension Our Service Dervos customer service is one of our biggest competitive advantages. In Dervos, we provide-   1.Quotation within 24 hours or no later than 3 days This will let you meet the quotation submission deadline and enhance your working efficiency   2.Weekly status report of your order In this way, you will have a clear picture of your order. You do not need to waste time on pushing us for status update   3.An 18-month warranty period A warranty certificate will issued after shipment and you will not have any concern after buying valves.   4.Solutions to complaints within 3 days Quick and responsible actions to complaints will protect your reputation and reduce the financial loss as much as possible.

Lubricated Plug Valve
1" 3000PSI Lubricated Plug Valve NPT A105 API6D Lever

1" 3000PSI lubricated plug valve is made according to API6D standard. The valve body is made of A105. It has the structural characteristics of inverted pressure balance type. Its connection mode is NPT. And it has lever operation mode.

Wafer Check Valve
API594 3" 150LB Dual Plate Wafer Check Valve API598 LCC

3" 150LB wafer check valve is made according to API594 standard. The valve body is made of A352 LCC + 316. It has the structural characteristics of double plate and built-in type. Its connection mode is wafer type.

RTJ, 1 600LB Forged Steel Globe Valve, Body LF2, API602
RTJ, 1" 600LB Forged Steel Globe Valve, Body LF2, API602, Hand Wheel

1" 600LB Forged Steel Globe valve is made according to API602 standard. The valve body is made of ASTM A350 LF2+STL. It has the structural characteristics of welded valve cover, needle valve disc. Its connection mode is RTJ. And it has Hand Wheel operation mode.

Swing Check Valve
RF Connection, 16'' 150LB Swing Check Valve, Body WCB, API594

16'' 150LB swing check valve is made according to API 594 standard. The valve body is made of A216 WCB+316. It has the structural characteristics of swing type and double disc wafer type. Its connection mode is RF.

A105 1/2”500PSI Floating Solid Ball Valve NPT Lever Handle
A105 1/2”500PSI Floating Solid Ball Valve NPT Lever Handle

1/2”500PSI Floating Solid Ball Valve is made according to BS5351 standard. The valve body is made of ASTM A105. It has the structural characteristics of Full Port, Two-piece, Floating Solid Ball, Fire-safe & Anti-static, Blow-out Proof Stem. Its connection mode is NPT. And it has Lever Handle operation mode.

Cast Steel Gate Valve
DN100 PN40 Cast Steel Gate Valve ASTM A216 WCB+STL RF H.W.

DN100 PN40 Cast Steel Gate Valve is made according to DIN3202 standard. The valve body is made of ASTM A216 WCB+STL. It has the structural characteristics of BB,O,S&Y and flexible wedge. Its connection mode is RF. And it has hand wheel operation mode.

Cast Steel Gate Valve
DN50 PN16 Cast Steel Gate Valve Body WCB EN1984 H.W.

DN50 PN16 Cast Steel Gate Valve is made according to EN1984 standard. The valve body is made of ASTM A216 WCB+STL. It has the structural characteristics of Bolted Bonnet, Flexible Wedge. Its connection mode is EN1092-1 B1. And it has hand wheel operation mode.

Floating Ball Valve
DN50 PN40 Floating Ball Valve F304 EN17292 Lever EN1092-1 B

DN50 PN40 ball valve is made according to EN 17292 standard. The valve body is made of A182 F304. It has the structural characteristics of floating ball, full bore, anti-fire, anti-static, and anti-flying valve stem. Its connection mode is EN1092-1 B. And it has lever operation mode.

4 125LB Y Type Strainer A395 1.4408 FF ASME B16.34
4" 125LB Y Type Strainer A395 1.4408 FF ASME B16.34

4” 125LB Y Type Strainer is made according to ASME B16.34 standard. The valve body is made of Ductile Iron A395. It has the structural characteristics of Y-Type, Body-Bonnet Bolted Connection. Its connection mode is FF. 

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.

Home

Products

about

contact