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.
16" 150LB double eccentric butterfly valve twins are made according to API 609 standard. The valve body is made of ASTM A216 WCB. It has the structural characteristics of high performance and dual eccentricity. Two valves share one worm gear head. Its connection mode is wafer. And it has turbine operation mode.
1" 300LB steam trap valve is made according to GB/T22654-2008 standard. The valve body is made of LF2 CL1. It has the structural characteristics of thermodynamic type. Its connection mode is RF.
2" 300LB change over valve is made according to ASME B16.34 standard. The valve body is made of ASTM A216 WCB. It has the structural characteristics of plug cover, the overall internal material is F316L. Its connection mode is RF. And it has Handwheel operation mode.
12" 1500LB cast steel slab gate valve is made according to API 6D standard. The valve body is made of A216 WCB. It has the structural characteristics of body cover bolt, full flow, cleanable pipe, anti-fire design. Its connection mode is RTJ. And it has gearbox operation mode.
DN200 PN16 angle bellows sealed 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, exposed pole bracket, angle type, bellow seal. Its connection mode is RF. And it has hand wheel operation mode.
DN300 PN63 ball valve is made according to API 6D standard. The valve body is made of ASTM A105. It has the structural characteristics of fixed ball, full bore, anti-fire, anti-static, and anti-flying valve stem. Its connection mode is EN1092-1 D. And it has worm wheel operation mode.
16" 900LB ball valve is made according to API 6D standard. The valve body is made of A350 LF2. It has the structural characteristics of fully welded, fixed ball and full bore. Its connection mode is BW. And it has turbine operation mode.
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...
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 ...
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....
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