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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...

Gate Valve
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2" 900LB Pressure Seal Bonnet Gate Valve F91 ASME B16.34 BW

2”900LB Pressure Seal Bonnet Gate Valve is made according to ASME B16.34 standard. The valve body is made of A182-F91. It has the structural characteristics of PSB, OS&Y,Solid Wedge . Its connection mode is BW sch 80 ASME B16.25. And it has Handwheel 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:

    A182-F91
  • Method of Operation:

    A182-F91
Inquiry now
Product Detail

Product Description

 

Type

Gate Valve

Size

2”

Pressure

900LB

Connection

BW sch 80 ASME B16.25

Body Material

A182-F91

Design Norm

ASME B16.34,API602

BW end size

ASME/B16.25

Test & Inspection Code

API 598

Temperature

-29 ~ 649°C

Applicable Medium

Water, Oil and Gas

 

Features

1.Manufactured from F91 alloy steel, offering exceptional high-temperature strength and reliability for 900LB pressure class applications.

2.Pressure seal bonnet gate valve with BW ends and ASME B16.34 compliance ensures secure sealing and long-lasting performance in critical service conditions.

 

Technical Drawing

Pressure Seal Gate Valve

Dimension Checking

Pressure Seal Bonnet Gate Valve

Pressure Testing

Pressure Seal Bonnet Gate Valve

Nameplate & Packing

Pressure Seal Bonnet Gate Valve

Inspection Report

Pressure Seal Bonnet Gate ValvePressure Seal Bonnet Gate ValvePressure Seal Bonnet Gate ValvePressure Seal Bonnet Gate Valve

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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.

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