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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...

What are the differences between globe valves and gate valves?
What are the differences between globe valves and gate valves?
2025-12-12

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....

Knife Gate Valve
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2" 150LB Knife Gate Valve CF8 Lug Handwheel

2" 150LB knife gate valve is made according to MFS standard. The valve body is made of ASTM A351 CF8. It has the structural characteristics of bilateral sealing and with flow deflector. Its connection mode is lug. 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:

    ASTM A351 CF8
  • Method of Operation:

    Hand Wheel
Inquiry now
Product Detail

Product Description

Type

Knife Gate Valve

Size

2"

Pressure

150LB

Connection

Lug

Operation

Hand Wheel

Body Material

ASTM A351 CF8

Design Norm

MFS

Flange Connection

AS2129 TABLE E

Face to Face

EN558

Test & Inspection Code

MSS SP-81

Applicable Medium

Water, Oil and Gas

Features

1. Simple structure, easy to manufacture and maintain;

2. Simple structure, low fluid resistance, good sealing performance, and fast opening and closing.

Technical Drawing

Dimension Checking

Pressure Testing

Nameplate & Packing

Inspection report

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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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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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