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...

LF2 Cryogenic Ball Valve
加载中...

Extended Stem Cryogenic Ball Valve LF2 1500LB BW

  • Payment:

    30% T/T When Order, 70% T/T Before Shipment
  • Product Origin:

    China
  • Shipping Port:

    Shanghai China
  • Lead Time:

    35~60 days Ex Works After Order Confirmation
  • Material:

    Low Temperature Steel Ball Valve, A350 LF2
  • Method of Operation:

    Gearbox Operated Ball Valve
Inquiry now
Product Detail

The Class 1500 4'' cryogenic ball valve is designed with extended stem for low temperature application. The valve is made of LF2 with fully welded body, butt weld end and gearbox operation. 

 

Design Feature
-Fully welded & forged body
-Extended stem or bonnet
-Full port design and piggable
-Anti blow-out stem
-Antistatic function
- Automatic cavity relief
-Bi-directional seat and DBB design
-With stem and seat grease fittings

 

Quick Detail

Type

Ball Valve

Size

4"

Pressure

ANSI 1500

Construction

One-Piece Body, Fully Weld, Extended Stem or Bonnet, Full Port

Connection

Butt Weld

Operation

Gearbox Operated

Body Material

Low Temperature Steel A350 LF2

Design Code

API 6D

Pressure & Temp

ASME B16.34

End to End Dimension

ASME B16.10

End Connection

ASME B16.25

Inspection

API 598

Temperature Range

-46℃~+200℃

Media

Oil, Water, Gas

 

Related Knowledge
What is the difference between full bore and reduced bore ball valve?

The internal diameter of a full bore ball valve is the same as the inner diameter of the pipe. The full bore ball valve has little resistance and pressure drop to the flow. Plus, the full bore ball valve is piggable.

However, the internal diameter of a reduced port (standard port) ball valve is smaller than the inner pipe size. Flow restriction caused by the reduced port will cause a pressure drop. And sometimes a pig to clean the pipe will get stuck in the reduced port ball valve.

 

 

 

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
Cryogenic Floating Ball Valve 4Inch 300LB RF Lever
Cryogenic Floating Ball Valve 4Inch 300LB RF Lever

The 4 inch cryogenic ball valve, designed as per API609, has many parts equipped RPTFE --It has the lowest coefficient of friction and the best corrosion resistance of any known plastic material, so that the valve can handle quite extreme situations.

Bronze Gate Valve
1 Inch 800LB Bronze Gate Valve API602

Differing 1/4 inch to 3 inch, this gate valve is made of B62 bronze according to API602. No matter what pressure rating, thread design or size you require, Dervos has a large selection of valves to meet your needs.

Gate Valve
API602 1" 800LB Forged Steel Gate Valve A105N SW

1" 800LB gate valve is made according to API 602 standard. The valve body is made of ASTM A105N. It has the structural characteristics of rising-stem. Its connection mode is SW. And it has the operation mode of installing electrical equipment with a light rod.

Butterfly Valve
DN300 PN25 Triple Eccentric Butterfly Valve WCB Turbine

DN300 PN25 Triple Eccentric Butterfly Valve is made according to EN 593 standard. The valve body is made of A216 WCB. It has the structural characteristics of Triple offset, multi-layer sealing and structural length of 83 mm. Its connection mode is LUG. And it has turbine operation mode.

V-port ball valves
150LB V ball valve Duplex Stainless Steel 4A

The 150LB ball valve, made of Duplex stainless steel 4A, has a special V port ball. The valve is particularly suitable for media containing fibers, tiny solid particles, slurry and so on. 

DIN Globe Valve Angle Type
Angle Type Globe Valve DN65 PN16 GS-C25 Rising Stem

The DN65 PN16 angle type globe valve is made of cast steel 1.0619 body and ss304 trim material, with rising stem, handwheel, RF flange.  Quick Detail Type Globe Valve Norminal Size DN 65 NorminalPressure PN 16 Construction Angle Pattern, BB ConnectionType Flanged Operation Handwheel Design Code DIN 3356 Face to Face EN 558 Connection EN1092 Test & Inspection EN12266 Body Material GS-C25 (1.0619) ApplicableTemp -29℃~+425℃ Application WOG Related Knowledge Why use an angle type globe valve? Angle globe valve turns the flow direction by 90 degrees without using an elbow or the extra pipe weld, which reduce the number of joints on the pipeline, save the installation time, and reduce the pressure drop & flow resistance. The angle pattern globe valve are used for application with periods of pulsating flow, since they are able to handle slugging effect. 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.

6 300LB Axial Flow Check Valve, Wafer Type, Body SS2205
6" 300LB Axial Flow Check Valve, Wafer Type, Body SS2205, API594

6" 300LB Axial Flow Check valve is made according to API594 standard. The valve body is made of SS2205. It has the structural characteristics of Silent type. Its connection mode is Wafer Type.

RF, DN32 PN40 Steam Trap Valve, Body A105,
RF, DN32 PN40 Steam Trap Valve, Body A105, GB/T22654

DN32 PN40 Steam Trap valve is made according to GB/T22654-2008° standard. The valve body is made of A105. It has the structural characteristics of Bimetallic sheet, reduced diameter and structural length of 180mm. Its connection mode is RF.

DN15 PN63 Forged Steel Globe Valve A105N+STL
DN15 PN63 Forged Steel Globe Valve A105N+STL EN1092-1 B

DN15 PN63 Forged Steel Globe Valve is made according to BS 5352 standard. The valve body is made of A105N+STL. It has the structural characteristics of through way type, bolt bonnet and structural length of 130mm. Its connection mode is EN1092-1 B. And it has hand wheel operation mode.

Ball Valve
1/2'' 150LB Forged Steel Floating Ball Valve API608

Made of A182-F316L, 1/2’’ 150LB ball valve is made according to API 608 standard. It has the structural characteristics of floating ball and two-piece ball valve.Its connection mode is RF and there is a handle operation mode.

Globe Valve
DN25 PN63 Forged Steel Globe Valve BS5352 Handwheel A105N SS304

DN25 PN63 globe valve is made according to BS5352 standard. The valve body is made of A105N+SS304. It has the structural characteristics of bolt cover, straight through type. Its connection mode is EN1092-1 D. And it has hand wheel operation mode.

trunnion mounted ball valve
3 Piece Position Type Ball Valve, ASTM A105N, Class 800, 1 Inch

China Carbon Steel Ball Valve Provider Offers 3 Piece Position Type Ball Valve, ASTM A105N, Class 800, 1 Inch, Free Floating Ball, API 608, BS 5351.

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