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Why Bronze Butterfly Valves Are Widely Used in Marine Applications

January 19, 2026

Bronze butterfly valves are widely used in marine and shipbuilding applications due to their excellent corrosion resistance, mechanical stability, and long service life in seawater environments.

Excellent Corrosion Resistance in Seawater

Marine piping systems are continuously exposed to seawater, salt spray, and humid conditions. Bronze alloys, especially aluminum bronze materials such as C95400, offer outstanding resistance to seawater corrosion, dezincification, and biofouling. This makes bronze butterfly valves a reliable choice for long-term marine service.

Reliable Performance for Marine Systems

Bronze butterfly valves are commonly applied in:

Seawater cooling systems/Ballast water systems/Firefighting systems/General marine piping systems

Compared with carbon steel or cast iron, bronze components maintain stable mechanical properties and sealing performance under harsh marine conditions, reducing the risk of leakage and premature failure.

Compatibility with Marine Classification Requirements

For shipowners and shipyards, compliance with classification society rules is essential. Bronze butterfly valves can be manufactured to meet the requirements of major marine classification societies such as ABS, DNV, CCS, and LR, ensuring safety and regulatory acceptance for marine projects.

Long Service Life and Lower Maintenance Cost

Although bronze butterfly valves may have a higher initial cost than standard materials, their superior corrosion resistance significantly reduces maintenance frequency and replacement costs over the vessel’s service life. This makes them a cost-effective solution for marine operators.

Conclusion

Due to their corrosion resistance, reliability, and compliance with marine standards, bronze butterfly valves remain one of the preferred valve solutions for marine and shipbuilding applications.

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!

Marine Bronze Butterfly Valve

January 15, 2026

Certified Reliability for Marine & Offshore Applications

The Marine Bronze Butterfly Valve is specially engineered for shipboard and marine piping systems, where long-term reliability and corrosion resistance are essential. Manufactured from high-quality bronze or aluminum bronze alloys, this valve delivers excellent performance in seawater, salt spray, and harsh marine environments.

With a compact structure and quick quarter-turn operation, it is an ideal solution for both on/off service and flow regulation in marine applications.

Key Advantages

Outstanding Seawater Corrosion Resistance
Marine-grade bronze and aluminum bronze materials provide excellent resistance to seawater corrosion, erosion, and biofouling, ensuring long service life in demanding marine conditions.

Compact & Lightweight Design
The butterfly valve design minimizes weight and installation space, making it especially suitable for shipboard systems with limited space.

Quick & Efficient Operation
A 90° quarter-turn mechanism allows fast opening and closing, improving operational efficiency and system response.

Flexible Installation Options
Available in wafer, lug, and flanged types, compatible with various marine piping standards.

Multiple Actuation Options
Manual lever, worm gear, pneumatic, or electric actuators are available to meet different operating and automation requirements.

Classification Society Approval Available

The Marine Bronze Butterfly Valve can be supplied with classification society certification, including:

ABS (American Bureau of Shipping)/DNV (DNV – Maritime & Offshore)

CCS (China Classification Society)/LR / LRS (Lloyd’s Register)

Certification can be provided according to project or shipowner requirements, ensuring full compliance with international marine standards.

Typical Marine Applications

Seawater cooling systems/Ballast water systems/Fire-fighting pipelines

Freshwater and service water systems/Offshore and marine auxiliary systems

Widely used on commercial vessels, offshore platforms, and marine engineering projects.

Materials & Specifications (Typical)

Body / Disc: Bronze or Aluminum Bronze (e.g. C95400, C95800)

Stem: Stainless steel or corrosion-resistant alloy/Seat: EPDM, NBR, PTFE

Size Range: DN40 – DN1200 (1½″ – 48″)/Pressure Rating: PN6 – PN16 / ANSI Class 125 – 150

Operation: Lever, Gear, Pneumatic, Electric

Other materials and configurations are available upon request.

A Trusted Choice for Marine Service

Combining marine-grade materials, flexible certification options, and reliable performance, the Marine Bronze Butterfly Valve is a proven solution for shipowners and marine engineers seeking durability, safety, and long-term value.

Message to Our Global Clients — 2026 Tianjin Tanghai Dongyang Valve

January 2, 2026

As we enter 2026, we extend our sincere appreciation to all our clients—both new and long-standing—for your trust and continued cooperation.

As a dedicated manufacturer of marine valves, we remain focused on precision engineering, reliable performance, and strict quality control. Every product we deliver is designed to meet the demanding requirements of marine and offshore applications, ensuring safety, durability, and compliance with international standards.

In the year ahead, we will continue to strengthen our manufacturing capabilities, optimize production processes, and invest in technology and quality systems to better support our customers worldwide.

2026 marks another step forward in our commitment to long-term partnerships and sustainable growth. We look forward to working closely with you and contributing to your success through dependable products and professional service.

Thank you for choosing us as your trusted marine valve manufacturer.

U-Type Marine Concentric Butterfly Valve Introduction

November 28, 2025

1. Overview

The U-type marine concentric butterfly valve is a wafer-style soft-seated valve designed for shipboard piping systems.
Featuring a U-shaped body groove and a concentric disc-shaft structure, the valve provides reliable shut-off performance, excellent corrosion resistance, and easy installation with marine-standard flanges.
It is widely used for seawater, cooling water, ballast water, fire-fighting, and various utility lines on vessels.

2. Design Characteristics

Concentric Structure (Center-Line Design)
The disc and shaft share the same centerline, providing stable torque, low operating resistance, and tight shut-off.

U-shaped Groove Body
Ensures accurate alignment with JIS / DIN / ANSI marine flanges and enhances sealing integrity.

Soft Seat Sealing
EPDM, NBR, PTFE, or Viton seats deliver excellent sealing performance and low leakage (Bubble-Tight).

Lightweight & Space-Saving
Compact body design is ideal for marine engine rooms and confined piping spaces.

Quick Operation
90° rotation with lever, gear operator, pneumatic actuator, or electric actuator.

Excellent Corrosion Resistance
Common marine materials such as C95400, C95800, CF8M, and duplex stainless steel ensure long service life in seawater applications.

3. Typical Materials

Body: Aluminum Bronze C95400 / C95800/Stainless Steel CF8 / CF8M

Duplex Stainless Steel S31803 / S32750/Ductile Iron with marine epoxy or rubber lining

Disc: C95400 / C95800 / SS316 / SS316L/Duplex Stainless Steel/Ni-plated Ductile Iron

Shaft： SS316/Duplex Steel

Seat: EPDM (recommended for seawater)/NBR (for oil-related media)/PTFE (for corrosive chemical media)/Viton (for high temperature or special fluids)

4. Applications

U-type concentric butterfly valves are commonly used in:

Seawater cooling systems，Ballast water pipelines，Engine room and machinery space piping，Fire-fighting lines，HVAC systems，Fresh water and utility pipelines

Water treatment and bilge systems

5. Applicable Standards

Marine Class Approvals: DNV / ABS / LR / BV / NK / RINA

Face-to-Face: ISO 5752 / EN 558

Flanges: JIS 5K/10K, DIN PN10/16, ANSI Class 150

Actuator Mounting: ISO 5211

Available with EN 10204 3.1 / 3.2 Certificates

Introduction of SS304 Disc for Concentric Type Butterfly Valve

November 14, 2025

The SS304 disc is one of the most commonly used materials for concentric type butterfly valves, offering an excellent balance of corrosion resistance, strength, and cost-effectiveness.

center-line butterfly valve plate disc parts (12)

SS304 (AISI 304 / ASTM A351 CF8) is an austenitic stainless steel containing approximately 18% chromium and 8% nickel, which provides outstanding resistance to oxidation and a wide range of mild corrosive environments.

When used in concentric butterfly valves, the SS304 disc ensures:
Good corrosion resistance in air, water, and most neutral or mildly corrosive fluids.

High strength and durability, making it suitable for both industrial and marine applications.

Smooth surface finish, minimizing flow resistance and preventing medium buildup.

Compatibility with various seat materials (such as EPDM, NBR, or PTFE) for versatile service conditions.

Typical applications include water treatment, HVAC systems, general industry, shipbuilding, and chemical processes where moderate corrosion resistance is required.

Full Lined PTFE Butterfly Valve

October 18, 2025

What is a Full Lined PTFE Butterfly Valve?

A full-lined PTFE butterfly valve is a butterfly valve whose wetted (fluid-contact) surfaces (body interior + disc / plate + sometimes stem bushing, etc.) are fully lined with PTFE (Polytetrafluoroethylene) or a similar chemically inert fluoropolymer. The lining protects the metal against corrosion and chemical attack. Useful for acids, alkalis, aggressive chemicals, etc.
Key features often include:
Full PTFE lining: Body & disc (sometimes liner also for shaft sealing) so that the medium does not contact the metallic parts.
Valve types: Wafer, Lug, Flanged, split-body, two-piece body, etc.
Pressure ratings: Commonly PN10, PN16, ANSI 150 / Class 150, sometimes lower / higher depending on size & design.
Size range: From small (DN50 / 2″) up to large (DN600, DN1200 etc) depending on manufacturer.
Temperature range: Depends on PTFE and other materials. Usually −20°C up to about +150°C (sometimes more, sometimes less).
Body and disc materials: Stainless steel, cast iron, ductile iron, carbon steel, etc, but protected by the PTFE lining.

Pros & Cons

Pros	Cons / Limitations
Excellent chemical resistance (acids, alkalis, corrosives)	PTFE lining adds cost; thick lining can reduce opening torque / increase weight in large sizes.
Non-stick, easy cleaning, long life in aggressive media	Limited temperature range (PTFE softens above certain temps / creep can be issue at high temp and load).
Good sealing (if well designed)	Mechanical strength of valve body still matters; PTFE can deform under high pressure differential if design not proper.
Can prevent metal contamination for purity/clean fluid applications	Repair/lining replacements can be more complex than unlined types.

What to Check / Ask For When Buying
If you are selecting a supplier or model, consider:
1.Lining quality & method
How is the PTFE liner attached (bonded, mechanically fixed)?
Is the disc also lined or just the body?
2.Pressure & temperature ratings
At your operating temperature & pressure, is the PTFE specification valid? (PTFE has limits).
Overpressure, vacuum capability.
3.Standards & test certificates
Compliance: API609, EN593, EN12266, ISO5752, ANSI, etc.
Leakage class, tightness tests.
4.Connection type
Wafer, lug, flange types. Which suits your piping system.
5.Actuation
Manual lever, gear, pneumatic, electric. Torque required (PTFE adds friction sometimes).
6.Maintenance
Can the liner/disc be replaced or serviced? Spare parts available.
Expected lifetime under your fluid & environment.
7.Chemical compatibility
The specific chemicals, concentration, temperature, etc. Make sure PTFE is compatible.

C95200 Aluminum Bronze Disc for Centric Butterfly Valves

September 28, 2025

1. Material Description
Grade: C95200
Alloy Name: Aluminum Bronze
Main Chemical Composition:
Cu ≈ 85% Al ≈ 10% Fe ≈ 3–4% Ni/Mn: trace elements
Standards: ASTM B148 / B584
Key Properties: High strength, excellent wear resistance and outstanding corrosion resistance in seawater and mildly corrosive environments.
2. Product Features
Seawater Corrosion Resistance – Exceptional performance in marine and offshore conditions.
High Mechanical Strength – Higher tensile and yield strength compared to tin bronze, suitable for demanding applications.
Excellent Wear Resistance – Ensures long-term sealing stability under frequent opening and closing.
Soft-Seat Compatibility – Works with EPDM, NBR, Viton and other elastomers for zero-leakage sealing.
3. Applications
Marine centric (soft-seated) butterfly valves.
Ballast water, seawater cooling, fire-fighting, desalination and other pipeline systems.
Ports, docks, offshore platforms and chemical plants requiring corrosion-resistant piping.
4. Specifications
Size Range: DN50 – DN1200 (or per customer drawing).
Pressure Ratings: PN10 / PN16 / Class 150.
Design Options: Pin and pinless disc structures available.
Surface Finish: Precision machined and polished; optional anti-rust coating.
5. Quality Assurance
100% spectrographic analysis of raw materials.
Radiographic/ultrasonic testing of castings and hydrostatic tests.
Dimensional accuracy and surface roughness in compliance with international standards.
6. Supply & Customization
OEM/ODM production according to customer drawings or samples.
Logo or marking customization available.
English technical documents, 3D drawings and export packaging provided.

C83600 Concentric Butterfly Valve Disc – Detailed Introduction

September 15, 2025

1. Material Description

C83600 belongs to Leaded Tin Bronze, one of the internationally recognized and widely used materials for marine valves.

Main Composition:

Copper (Cu): ~83%

Tin (Sn): ~7%

Lead (Pb): ~7%

Zinc (Zn): ~3%

Standards: Complies with ASTM B62, SAE 40

Material Properties:

High strength and toughness

Excellent corrosion resistance, especially suitable for seawater and salt spray environments

Superior casting performance and machinability

Good self-lubricating ability and excellent anti-galling performance

2. Advantages in Butterfly Valve Discs

Seawater Corrosion Resistance
C83600 maintains stable corrosion resistance in chloride-rich seawater, preventing pitting or dezincification of the disc.

Stable Sealing Performance
The disc has a high surface finish and good machinability, ensuring a precise fit with soft seats such as EPDM and NBR, and guaranteeing zero or minimal leakage.

Wear and Erosion Resistance
Under frequent operation or high-velocity seawater flow, discs made of C83600 offer long service life and are resistant to wear and erosion.

Excellent Castability and Machinability
Suitable for casting complex disc structures, with dense microstructure and high machining precision, ensuring overall valve performance.

High Reliability
Meets the requirements of classification societies such as ABS, LR, DNV, BV, and is widely used in marine systems.

3. Applications

C83600 discs are widely applied in concentric soft-seated butterfly valves for marine service, with typical applications including:

Ballast Water Systems

Seawater Cooling Systems

Fire-Fighting Piping Systems

Bilge, sewage, and seawater pipelines

4. Typical Properties

Property	Value Range	Remarks
Tensile Strength	≥ 250 MPa	Ensures strength and load capacity
Yield Strength	≥ 100 MPa	Resistant to deformation under load
Brinell Hardness (HB)	65 – 85	Balanced hardness for wear resistance and machinability
Elongation	≥ 10%	Provides toughness and impact resistance
Density	~ 8.8 g/cm³	Dense and stable material structure
Corrosion Resistance	Excellent	Especially suitable for marine environments

Bronze Disc for Butterfly Valve

September 4, 2025

Product Description

The bronze disc is one of the key components of a butterfly valve, mounted inside the valve body and connected with the stem and seat to control on-off and flow regulation. Manufactured from high-quality bronze alloys, the disc provides excellent corrosion resistance and mechanical strength, making it especially suitable for seawater, brine, and mildly corrosive environments.

1，Materials

C95400，C95500，C95800，C83600，RG102，Typical materials include:

C95400 Aluminum Bronze，C95500/C95800 Nickel Aluminum Bronze

C83600 Cast Bronze，RG10 Naval Bronze

3，Features & Advantages

Excellent corrosion resistance for seawater and saline environments

High strength and toughness for reliable long-term operation

Wear resistance for extended valve service life

Precision casting ensures perfect sealing with the valve seat

4，Applications

Marine piping systems (ballast water, cooling water, fire-fighting lines)

Desalination plants

Offshore engineering platforms

Brine and chemical pipelines

Concentric Type Butterfly Valve with Pin and Pinless

August 22, 2025

Concentric Butterfly Valve with Pin

Structure: The disc is fixed to the stem by pins, ensuring direct and reliable connection.

Advantages:

Simple manufacturing process and easy assembly.

Reliable torque transmission between the disc and the stem, not easy to slip.

Suitable for larger torque and frequent open/close operations.

Disadvantages:

Pin holes may become corrosion points, especially in seawater or corrosive media.

Possible leakage through pin holes.

Not as precise or tight as pinless design in high sealing requirements.

Concentric Butterfly Valve without Pin (Pinless)

Structure: The disc is fixed to the stem by interference fit, keyway, or integral casting, without using pins.

Advantages:

Eliminates pin holes, reducing leakage risk.

Better corrosion resistance, especially suitable for marine, seawater desalination, and offshore applications.

Stronger integrity between disc and stem, cleaner appearance.

Disadvantages:

Higher manufacturing and assembly precision required.

Maintenance is more complex if the connection loosens.

Generally higher cost than pinned design.

With Pin → Traditional design, lower cost, suitable for general conditions.

Pinless → Better corrosion resistance and sealing performance, more suitable for marine use and high-end markets.