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Cast Steel CF8 DN250 PN16 RF Flange Double Offset Butterfly Valve With Pneumatic Actuator and HandWheel

  • Nominal Diameter: DN250
  • Bore: Full Bore
  • Nominal Pressure: PN16
  • Material: CF8
  • Operation: Pneumatic Actuator and Handwheel
  • Design Standard: API609
  • Test/Inspection: API598
  • End Connection: RF FLANGE
  • Flange standard: EN1092-1,ASME/ANSI B16.5
  • Top Flange: ISO5211

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Product Description:

What is flanged double offset butterfly valve

Flanged double-offset butterfly valve is a butterfly valve with a flange in the connection mode and a double-offset structure in the design. This design is designed to provide higher sealing performance and longer life, suitable for industrial applications requiring high-performance butterfly valves, such as petroleum, chemical, water treatment and other fields.

How do flanged double-offset butterfly valves work

The flanged double-offset butterfly valve controls the opening and closing of the fluid channel by rotating the eccentric design of the butterfly plate. In the initial state, the disc is nested in the seat to block the fluid passage. When the valve needs to be opened, the stem rotation causes the disc to rotate around the axis, gradually opening the fluid passage. The double offset design reduces the torque required to open the valve, while reducing fluid resistance when the valve is fully open, allowing for precise flow regulation. When the valve is closed, the disc returns to the seat position, blocking the fluid passage and completing the valve-closing process. This working principle makes flanged double-offset butterfly valves suitable for industrial applications requiring high-performance fluid control.

Flange double offset butterfly valve product overview

1. Design features
Double offset design, including eccentricity in axial and radius direction, reduces operating torque, improves sealing performance, reduces wear and prolonging life.
The flange connection ensures that the valve is firmly installed on the pipe for easy installation and maintenance.

2. Body material
High-strength metal materials, such as carbon steel, stainless steel, special alloys, etc., suitable for high temperature, high pressure and corrosive media.

3. Valve seat and plate
Metal to metal sealing surface, the use of high wear resistance, high strength metal material, to provide reliable sealing performance and durability.

4. Flange standards
Comply with international standards, such as ASME, DIN, etc., to ensure compatibility with various piping systems.

5. Ease of operation
The double offset design reduces the operating torque, making the opening and closing of the valve more convenient, increasing the convenience of operation.

6. Applicable pressure and temperature range
Suitable for a wide range of pressure grades and temperatures, giving it flexibility in a wide range of industrial applications.

7. Fluid control capability
Provides reliable fluid control capability for a wide range of applications to regulate and disconnect fluid media.

8. Application
Widely used in petroleum, chemical, electric power, water treatment and other industrial fields, especially suitable for the sealing performance and light operation requirements of the occasion.

9. A variety of operating devices
Equipped with hand wheel, worm gear, electric actuator, pneumatic actuator and other operating devices to adapt to different working conditions and automation requirements.

Flange double offset butterfly valve application site

1. Chemical industry: In the chemical production process, flange double offset butterfly valves are used to control the flow of various chemical media, including liquids, gases and corrosive media. Its corrosion resistance and high-temperature properties make it widely used in chemical systems.

2. Oil and gas industry: Used in pipeline transportation, oil field development and refineries. Flanged double offset butterfly valves handle media such as oil and natural gas and provide reliable fluid control under high pressure and high-temperature conditions.

3. Electric power industry: Used to control the flow of water, steam and other fluids in thermal power plants, nuclear power plants and other electric power facilities. Its fast opening and closing characteristics make it very useful in power systems that require rapid response.

4. Water treatment and sewage treatment: used to control the flow of tap water, sewage and industrial wastewater. The application of flanged double-offset butterfly valve in water treatment process helps to regulate the flow rate, control the pressure and realize the stable operation of the system.

5. Pharmaceutical industry: In pharmaceutical production, the need for strict fluid control of different media, flanged double offset butterfly valves can provide highly accurate flow control and operational flexibility.

6. Food and beverage industry: used to control various liquid and gaseous media in food and beverage production processes to ensure compliance with hygiene and quality standards.

7. Air conditioning and heating systems: Air conditioning systems used in buildings and industrial environments to control hot, cold, and air flow and regulate temperature and humidity.

8. Marine engineering: In Marine engineering such as offshore oil fields and offshore platforms, flanged double offset butterfly valves can be used to control the flow of seawater, oil and natural gas.

Standards for double offset butterfly valve

Valve Size DN50-1600, NPS 2-60
Pressure Rating N1-100, 150LB-600LB
Materials WCB, LCB, LC1, CF8, CF8M, CF3, CF3M, 4A, 5A, WC6, WC9, C95800
Design and Manufacturing Standards API 609, EN 593
Face to Face Standards API 609, EN 558, ISO 5752
Flange Size Standards ASME B 16.5, ASME B16.47, EN 1092-1, GOST 54432, JIS 2220
Stress Test Standards API 598, EN 12266-1
Fire Safety Test Standard API 607
Quality/Product Certifications ISO9001, ISO14001, ISO18001
Unorganized Emissions ISO 15848-1, API 622
National ACE NACE MR0175, NACE MR0103
Valve Operator Options hand wheel, worm wheel, electric actuator, pneumatic actuator, hydraulic actuator.
Shutdown Level API 598 (Zero leakage)
Aperture full aperture
Process Connection Types sandwich, flange, lug, welding


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