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ABS Certification in Marine Butterfly Valves

In the field of marine butterfly valves, ABS certification is a crucial qualification for entering the international shipbuilding and offshore markets. Here’s a detailed overview of how ABS certification applies to marine butterfly valves:

1. What is ABS Certification?

ABS (American Bureau of Shipping) is a globally recognized classification society that sets technical standards for the design, construction, and maintenance of ships and offshore structures.
An ABS certificate confirms that a product complies with ABS rules in terms of design, material selection, manufacturing process, and performance, making it suitable for harsh marine environments.

2. Types of ABS Certification for Butterfly Valves

Certification Type Description Typical Application
Type Approval Certificate (TAC) Confirms that a valve model meets ABS standards For batch production of standard models
Product Design Assessment (PDA) A detailed review of the valve’s design and intended service For customized or critical-use products
Manufacturing Assessment (MA) Assesses factory quality management and production capability Usually combined with TAC or PDA
Individual Product Certification Each valve is individually tested and inspected by ABS Required for critical shipboard systems (e.g., fire-fighting, ballast)

3. Common Marine Applications of ABS-Certified Butterfly ValvesBallast Water Systems

Cooling Water Circuits

Firefighting Systems

Fuel and Oil Lines

Sea Water Inlet/Outlet Systems

4. ABS Requirements for Marine Butterfly Valves

Item Requirement
Materials Must meet ASTM or marine-grade standards (e.g., CF8M, Bronze, Ductile Iron)
Design In accordance with ANSI/API or ISO standards and marine conditions (corrosion, vibration resistance)
Pressure Rating Commonly PN10, PN16, or 150 PSI
Tests Includes pressure, sealing, and performance testing
Documentation Material certificates, test reports, drawings, and QA documents are required for ABS review

DNV Certification in Marine Butterfly Valves

DNV certification plays a vital role in marine butterfly valves, signifying that the product complies with the standards set by Det Norske Veritas (DNV, formerly DNV-GL). It is a key requirement for entering the international shipbuilding and offshore engineering markets.

1. What is DNV Certification?

DNV (Det Norske Veritas) is a world-leading classification society and risk management organization.
DNV certification is a third-party verification that a product meets DNV’s classification standards in terms of design, materials, manufacturing, testing, and quality control.
It is widely applied to ships, offshore structures, and energy equipment that demand high reliability and safety.

2. DNV Requirements for Marine Butterfly Valves

In the field of marine butterfly valves, DNV certification involves the following aspects:

1. Product Design and Drawing Approval

Valve designs must be submitted for review by DNV, including:

Structural drawings

Material specifications

Working pressure

Temperature range

Sealing structure and configuration

2. Material Certification

All pressure-bearing parts must use DNV-approved materials.
Material certificates conforming to EN 10204 3.1 or 3.2 are usually required.

3. Inspection of Castings or Forgings

DNV requires NDT (non-destructive testing) on valve bodies and discs, including:

Ultrasonic testing (UT)

Radiographic testing (RT)

Magnetic particle testing (MT) or dye penetrant testing (PT)
These inspections must be witnessed or reviewed by a DNV surveyor.

4. Performance Testing

Valves must undergo:

Shell pressure tests

Leakage/sealing tests
Typically carried out under the supervision of a DNV inspector.

For specific applications, additional tests may be required:

Low-temperature impact test

Fire safety test

Corrosion resistance tests (e.g., NACE standards)

5. Manufacturing Supervision and Final Acceptance

DNV monitors the manufacturing process.
A DNV-signed Product Certificate must be issued upon final acceptance.

3. Common Applications of DNV-Certified Marine Butterfly Valves

Onboard Ship Systems:

Seawater cooling systems

Ballast water systems

Fire-fighting pipelines

Offshore Platforms:

Living quarters

Oil & gas transfer pipelines

LNG and Liquid Cargo Ships:

Cryogenic butterfly valves

Bi-directional sealing butterfly valves

4. Importance of DNV Certification for Export

DNV certification is a passport to major global markets such as:

Europe, Norway, Germany, the Netherlands, Singapore, Japan, etc.

Many renowned shipyards (e.g., Hyundai, Samsung Heavy Industries, Fincantieri) require valves to be certified by DNV or other major classification societies such as ABS, BV, or LR.

5. Recommended Information for Your Promotion

If you are involved in the casting of valve bodies, discs, or shafts, you can include the following statement in your promotional materials:

Our marine butterfly valve parts (valve body, disc, and shaft) are made from DNV-approved materials and produced under ISO 9001 quality control. We support our clients to pass DNV product certification through strict casting quality and mechanical property assurance.

Application of 2205 and 2507 in Marine Valves

2205 and 2507 are two types of duplex stainless steel that are widely used in marine valves (such as butterfly valves, gate valves, and check valves), particularly in environments where excellent corrosion resistance is required. Below is a comparison of their applications and key characteristics in marine valve usage:

I. Comparison of Basic Material Properties

Property 2205 (UNS S31803/S32205) 2507 (UNS S32750)
Type Duplex Stainless Steel Super Duplex Stainless Steel
Corrosion Resistance Excellent, suitable for most marine environments Superior, suitable for extreme marine and chemical environments
Pitting/Crevice Resistance Good Excellent
Chloride Stress Corrosion Resistance Strong Very strong
Yield Strength Higher than austenitic stainless steel (e.g., 316L) Even higher
Operating Temperature Range -50℃ to +300℃ -50℃ to +250℃ (recommended)
Cost Moderate High

II. Specific Applications in Marine Valves

1. Applications of 2205:

Seawater piping systems: Valves used in ballast water and cooling water systems

Desalination systems: Butterfly and gate valves

Liquid transportation systems on oil tankers and cargo vessels

Auxiliary systems in ships with moderate corrosion exposure, such as wastewater treatment systems

Cost-effective option for general-purpose marine valves

2. Applications of 2507:

Critical valves in high-corrosion, high-pressure environments such as deep-sea operation vessels and subsea equipment

LNG carriers and chemical tankers with extremely high corrosion resistance requirements

Shipboard systems exposed to high concentrations of chlorides or acidic gases (e.g., H₂S)

Ideal for scenarios requiring long-term, maintenance-free operation or extended service life

III. Material Selection Recommendations

Application Requirement Recommended Material
General seawater corrosion with cost-effectiveness priority 2205
Extreme corrosion (high chloride, high temperature, high pressure) 2507
Good weldability and high mechanical strength needed 2205 preferred
High safety margin and sufficient project budget 2507

In the marine valve industry, 2205 offers a cost-effective and corrosion-resistant solution suitable for wide application. 2507, on the other hand, delivers higher safety and durability in extremely harsh environments.

Selection Standard and Application Analysis for Marine Valve

Choosing the right valves for marine systems is crucial to ensure safety, reliability, and long-term performance in harsh offshore environments. Key selection criteria include:

1.1 Material Selection

Preferred Material: SS316, Duplex Stainless Steel, Bronze

Reason: High corrosion resistance in seawater, brine, and aggressive chemicals

Tip: Avoid carbon steel for exposed or submerged applications

1.2 Valve Type Selection

Valve Type Typical Marine Application
Butterfly Valve Ballast systems, cooling water lines
Check Valve Pump discharge, bilge lines, fire systems
Gate Valve Seawater intake, cargo pipelines
Globe Valve Flow regulation in steam or fuel systems
Ball Valve Quick shut-off for fuel, oil, or air lines

1.3 Standards & Classification

Ensure compliance with IMO, IACS, and classification societies such as:

DNV, ABS, LR, BV, CCS

Check for Fire-Safe, DNV-GL approved, or ISO/ANSI certified valves where required

1.4 Functional Requirements

Operating pressure & temperature

Flow direction and velocity

Manual, pneumatic, or electric actuation

End connection (flanged, wafer, threaded)

2. Application Analysis – Where Marine Valves Are Used

2.1 Engine Room Systems

Seawater cooling lines

Fuel oil, lubricating oil pipelines

Steam and condensate systems

Bilge and ballast systems

 2.2 Deck Systems

Cargo handling valves

Firefighting systems

Air vent check valves for tanks

2.3 Underwater / Hull Applications

Seachests

Overboard discharge valves

Bottom inlet valves

Note: Corrosion resistance and class approval are critical here

3. Additional Recommendations

Use soft-sealing valves (e.g., EPDM-lined butterfly valves) for low-pressure, non-critical lines

Use metal-seated valves for high-temperature or abrasive media

Choose compact wafer-type valves to save space in narrow engine rooms

Plan for easy maintenance access, especially in engine room clusters

Ensure spare part availability for long-term operation at sea

Tianjin Tanghai Valve Co., Ltd. is a professional marine valve manufacturer, including butterfly valve, check valve, gate /Knife gate valve. We have certificates: CE, ISO, BV, DNV foundry and products approval. Now we have our own independent R & D, manufacturing, assembly and warehousing workshops; we have professional pre-sale and after-sale technical support and perfect services. Below is our wafer butterfly valve of marine valves,if you need to check more information, please click here:https://www.tanghaivalve.com/wafer-type-butterfly-valve-th-btv-aw/.

Please contact us if you need more support, please contact us freely: info@tanghaivalve.com.

We are committed to “Build a top valve enterprise; Be a reliable partner!”Friends from all over the world are welcome to visit us for evaluation, guidance, and orders!

Common Faults and Maintenance of concentric Marine Butterfly Valves

Fault Cause Analysis Solution
Leakage Seat aging or wear Replace seat
Difficult operation Shaft rust or jamming Clean,lubricate,or replace shaft
Corrosion perforation Inadequate corrosion protection Repair by welding or replace valve
Handle damage Over-torque operation Replace handle and add torque limiter

Tianjin Tanghai Valve Co., Ltd. is a professional marine valve manufacturer, including butterfly valve, check valve, gate /Knife gate valve. We have certificates: CE, ISO, BV, DNV foundry and products approval. Now we have our own independent R & D, manufacturing, assembly and warehousing workshops; we have professional pre-sale and after-sale technical support and perfect services. Below is our wafer butterfly valve of marine valves,if you need to check more information, please click here:https://www.tanghaivalve.com/wafer-type-butterfly-valve-th-btv-aw/.

Please contact us if you need more support, please contact us freely: info@tanghaivalve.com.

We are committed to “Build a top valve enterprise; Be a reliable partner!”Friends from all over the world are welcome to visit us for evaluation, guidance, and orders!

Anti-Corrosion Technology for Marine Concentric Butterfly Valves

Body Coating: Epoxy coating, thermal zinc spray, FBE coating.

Disc Protection: Stainless steel or copper alloy with surface treatment.

Seat Protection: Modified rubber for seawater resistance.

Shaft Sealing and Corrosion Prevention: Special coating in shaft sealing chamber + corrosion-resistant O-rings.

Tianjin Tanghai Valve Co., Ltd. is a professional marine valve manufacturer, including butterfly valve, check valve, gate /Knife gate valve. We have certificates: CE, ISO, BV, DNV foundry and products approval. Now we have our own independent R & D, manufacturing, assembly and warehousing workshops; we have professional pre-sale and after-sale technical support and perfect services. Below is our wafer butterfly valve of marine valves,if you need to check more information, please click here:https://www.tanghaivalve.com/wafer-type-butterfly-valve-th-btv-aw/.

Please contact us if you need more support, please contact us freely: info@tanghaivalve.com.

We are committed to “Build a top valve enterprise; Be a reliable partner!”Friends from all over the world are welcome to visit us for evaluation, guidance, and orders!

Factors Affecting Sealing Performance of Concentric Soft Seal Butterfly Valves

Key Factors

  • Seat Material Selection: EPDM for seawater, NBR for oil, VITON for high temperature.
  • Machining Precision: Concentricity between valve body, disc, and seat.
  • Installation Position: Horizontal installation is preferred over vertical to avoid self-weight affecting sealing.
  • Torque Control: Excessive or insufficient torque may damage the seat.

Key Technical Points

  • Ensure concentricityamong body, disc, and seat.
  • Select suitable sealing materials.
  • Prevent high-temperature aging of the seat.
  • Apply anti-corrosion coatingsor linings to enhance seawater corrosion resistance.

Tianjin Tanghai Valve Co., Ltd. is a professional marine valve manufacturer, including butterfly valve, check valve, gate /Knife gate valve. We have certificates: CE, ISO, BV, DNV foundry and products approval. Now we have our own independent R & D, manufacturing, assembly and warehousing workshops; we have professional pre-sale and after-sale technical support and perfect services. Below is our wafer butterfly valve of marine valves,if you need to check more information, please click here:https://www.tanghaivalve.com/wafer-type-butterfly-valve-th-btv-aw/.

Please contact us if you need more support, please contact us freely: info@tanghaivalve.com.

We are committed to “Build a top valve enterprise; Be a reliable partner!”Friends from all over the world are welcome to visit us for evaluation, guidance, and orders!

Comparison Between Concentric and Double Offset Marine Butterfly Valves

Item Concentric Butterfly Valve Double Offset Butterfly Valve
Structure Disc center aligned with body centerline Disc center offset from body centerline
Sealing Type Mainly soft seal Soft+hard seal available
Operation Torque Low Slightly higher
ApplicationPressure Low to medium pressure(PN6-PN16) High pressure(PN25-PN40)
Cost Lower Higher
Typical Application General ship pipelines,ballast water systems High-ressure fire system,deck wash system

 

 

triple eccentric butterfly valve-wafer-butt weld (1)

Centerline butterfly valves are more economical and suitable for general marine pipelines, while double offset valves are better for high pressure, high temperature, or special media.

Tianjin Tanghai Valve Co., Ltd. is a professional marine valve manufacturer, including butterfly valve, check valve, gate /Knife gate valve. We have certificates: CE, ISO, BV,

DNV foundry and products approval. Now we have our own independent R & D, manufacturing, assembly and warehousing workshops; we have professional pre-sale and after-sale technical support and perfect services. Below is our wafer butterfly valve of marine valves,if you need to check more information, please click here:https://www.tanghaivalve.com/wafer-type-butterfly-valve-th-btv-aw/.

Please contact us if you need more support, please contact us freely: info@tanghaivalve.com.

Butterfly Valve Connection Standard

Butterfly valves are widely used in industrial applications for regulating flow and are manufactured according to several connection standards. These standards ensure compatibility, safety, and reliability. Below are the common connection standards for butterfly valves:

1. Flanged Connections

Butterfly valves with flanged ends are designed to mate with standard pipe flanges. The key standards for flanged connections include:

  • ASME B16.5: Pipe Flanges and Flanged Fittings (covers sizes from ½ inch to 24 inches, pressure classes 150 to 2500).
  • EN 1092-1: Flanges and their joints for PN-designated pressure systems.
  • ISO 7005-1: Metallic flanges for general purposes.
  • JIS B2220: Japanese flange standard.

2. Wafer Type Connections

Wafer butterfly valves are designed to fit between two pipe flanges using bolts or studs.

  • They are typically compatible with flange drilling patterns as per:
    • ASME B16.5
    • EN 1092
    • ISO 7005

3. Lug Type Connections

Lug butterfly valves have threaded inserts that allow them to be bolted to a pipe flange. Standards include:

  • ASME B16.5
  • EN 1092
  • ISO 7005

4. Grooved End Connections

For quick installation and connection to grooved piping systems.

  • AWWA C606: Grooved and shouldered joints.

5. Butt-Weld Connections

Less common for butterfly valves but occasionally used in specific applications.

  • ASME B16.25: Butt-welding ends.
  • ISO 9692: Welding preparation standards.

6. Standards for Specialized Applications

  • AWWA C504: For waterworks applications, especially large-diameter valves.
  • API 609: Butterfly valves for general-purpose applications.
  • MSS SP-67: Covers butterfly valves, general-purpose and high-performance types.

Key Considerations

  • Always ensure that the valve and mating components meet the same flange drilling patterns and pressure ratings.
  • Verify that the material of construction and dimensions meet the system’s operational requirements (temperature, pressure, medium compatibility).

Let us know if you’d like details on a specific standard!

The Application of Concentric type Butterfly Valve in Offshore Drilling Platforms

Concentric type butterfly valves find several applications in offshore drilling platforms due to their reliability, compact design, and ease of operation. Here’s how centerline butterfly valves are used in offshore drilling platforms:

  1. Flow Control in Seawater Systems:

Concentric butterfly valves are used to control the flow of seawater for different purposes:

Cooling Systems: Regulating seawater flow for cooling heat exchangers, engines, and other equipment.

Firewater Systems: Controlling seawater flow for firefighting purposes.

General Service Water: Regulating water flow for various platform operations.

  1. Fluid Control in Drilling Operations:

Drilling Mud Systems: Controlling the flow of drilling mud during drilling operations.

Mud Mixing Systems: Regulating the flow of chemicals and additives mixed with drilling mud.

  1. Ballast Systems:

Regulating the flow of seawater into and out of ballast tanks to adjust the platform’s stability and draft.

  1. Bilge and Drainage Systems:

Managing the discharge of bilge water and other drainage fluids from the platform to maintain a safe environment.

  1. Fire Protection Systems:

Concentric butterfly valves are used in firewater deluge systems and fire hydrant systems for emergency fire suppression.

  1. Potable Water Systems:

Regulating the flow of potable water for living quarters, kitchens, and other facilities on the platform.

  1. HVAC Systems:

Controlling the flow of seawater or chilled water for heating, ventilation, and air conditioning systems.

  1. Tank Farm Operations:

Handling the flow of various liquids such as crude oil, refined products, and chemicals within the platform’s storage tank systems.

Key Advantages in Offshore Applications:

Corrosion Resistance: Materials are selected to withstand corrosive marine environments.

Space Efficiency: Compact design is suitable for installations where space is limited, which is common in offshore platforms.

Quick Operation: Rapid opening and closing for emergency shutdown situations.

Reliable Sealing: Provides tight shut-off to prevent leaks, crucial for safety and environmental protection.

Safety and Emergency Shutdown Systems:

Concentric butterfly valves are often integrated into safety systems, including emergency shutdown (ESD) systems, to quickly isolate sections of piping in case of emergencies.

Concentric type butterfly valves play a vital role in offshore drilling platforms, ensuring efficient fluid control, safety, and environmental protection. Their versatility, reliability, and space-saving design make them well-suited for various critical applications in offshore oil and gas operations. Proper selection, installation, and maintenance of these valves are essential to ensure the safe and efficient operation of offshore drilling platforms.

Tianjin Tanghai Valve Co., Ltd. is a professional marine valve manufacturer, including butterfly valve, check valve, gate /Knife gate valve. We have certificates: CE, ISO, BV, DNV foundry and products approval. Now we have our own independent R & D, manufacturing, assembly and warehousing workshops; we have professional pre-sale and after-sale technical support and perfect services. Below is our wafer butterfly valve of marine valves,if you need to check more information, please click here:https://www.tanghaivalve.com/wafer-type-butterfly-valve-th-btv-aw/.

Please contact us if you need more support, please contact us freely: info@tanghaivalve.com.We are committed to “Build a top valve enterprise; Be a reliable partner!”Friends from all over the world are welcome to visit us for evaluation, guidance, and orders!

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