valve Archives

What Is C95400 Bronze Butterfly Valve Disc？

January 26, 2026

C95400 bronze is a commonly used aluminum bronze material for butterfly valve discs in marine and shipbuilding applications. It is well known for its excellent strength, corrosion resistance, and reliability in seawater environments.

Overview of C95400 Aluminum Bronze

C95400 is an aluminum bronze alloy primarily composed of copper, aluminum, and iron. This material offers a unique combination of high mechanical strength and outstanding resistance to corrosion, making it suitable for demanding marine conditions.

Compared with standard bronze materials, C95400 provides:

Higher tensile strength/Better wear resistance/Improved performance in seawater service

Why C95400 Is Used for Butterfly Valve Discs

The valve disc is the most critical component of a butterfly valve, as it is directly exposed to the fluid medium. In marine systems, seawater corrosion is one of the main challenges.

C95400 bronze butterfly valve discs are widely selected because:

They resist seawater corrosion and erosion

They maintain dimensional stability under pressure

They reduce the risk of pitting and surface degradation

These characteristics ensure smooth operation and reliable sealing performance throughout the valve’s service life.

Typical Marine Applications

C95400 bronze butterfly valve discs are commonly used in:

Seawater cooling systems/Ballast water systems/Fire main systems/General marine piping systems

They are especially suitable for vessels operating in harsh offshore or long-term seawater environments.

Compliance with Marine Standards

Butterfly valves equipped with C95400 bronze discs can be manufactured to meet the technical requirements of major marine classification societies, including ABS, DNV, CCS, and LR, ensuring acceptance by shipowners and shipyards worldwide.

Conclusion

Due to its excellent corrosion resistance, mechanical strength, and proven performance in seawater applications, C95400 aluminum bronze remains one of the preferred materials for butterfly valve discs in marine systems.

Tianjin Tanghai Dongyang Valve Co., Ltd. manufactures marine butterfly valves with C95400 bronze discs, offering reliable solutions for ABS, DNV, CCS, and LR certified marine projects.

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/double-flange-butterfly-valve-th-btv-df/

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!

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.

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.

Installation Locations of Dual-Plate Check Valves on Ships

August 8, 2025

Dual-plate check valves are mainly installed in pipelines where the medium flows in one direction, preventing backflow and reducing water hammer impact. On ships, typical installation locations include:

1. Engine Room Systems

Main Seawater Cooling System
Installed between the sea chest valve and the seawater pump, or between the pump outlet and the cooler, to prevent seawater from flowing back when the pump stops.

Freshwater Cooling System
Located at the outlet of the cooler to prevent backflow of cooling water to the equipment.

Fuel and Lube Oil Cooling Systems
Installed at the cooler or pump outlet to prevent oil from flowing back after the pump stops.

2. Ballast and Tank Systems

Ballast Water System
Between the ballast pump outlet and the ballast tanks to prevent water from flowing back, especially in systems with multiple pumps or tanks where each branch line needs a check valve.

Tank Drain Systems
To prevent liquid from one tank from flowing into another.

3. Firefighting and Emergency Systems

Firefighting System
At the outlet of the fire pump or branch lines to prevent backflow to the pump or other systems.

Emergency Pump Systems
To prevent cross-flow between the emergency pump and the main pump.

Installation Notes:

Can be installed horizontally (shaft vertical) or vertically (flow upward).

Should be located close to the pump outlet to minimize backflow and water hammer.

The arrow on the valve body must align with the flow direction of the pipeline.

SS316 Wafer Type Single Disc Check Valve

May 7, 2025

Reliable Backflow Protection – Built for Harsh Marine and Industrial Environments

Product Overview

Our SS316 Single Disc Check Valve is designed for high-performance backflow prevention in demanding environments such as marine systems, chemical plants, and water treatment facilities. Made from 316 stainless steel, it offers exceptional resistance to corrosion, even in seawater and aggressive media.

With its compact wafer-type body and single disc design, it ensures fast response, minimal pressure drop, and easy installation between flanges.

Key Features

Material: SS316 Body & Disc – excellent corrosion resistance

Design: Compact wafer type, single disc for fast shut-off

Seal Options: EPDM / NBR / PTFE – compatible with various media

Installation: Horizontal or vertical (upward flow)

Pressure Rating: PN10 / PN16 / ANSI150 available

Sizes: DN40 to DN600 (larger sizes customizable)

Applications

Marine pipelines (ballast systems, cooling water, bilge lines)

Offshore platforms

Chemical and pharmaceutical industries

Water treatment & desalination systems

Pump discharge lines

Why Choose Us

Over 15 years in precision casting and valve component manufacturing

OEM/ODM services available

Fast lead times, reliable quality

Export-ready with international shipping & documentation support

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!

Connection Standard of Dual Plate Check Valve

January 6, 2025

The connection standard of a Dual Plate Check Valve primarily refers to the standards governing the face-to-face dimensions, flange compatibility, and pressure ratings. These standards ensure that the valve can be installed easily in various pipeline systems with flanged connections.

Key Connection Standards for Dual Plate Check Valves:

1. API 594 – Check Valve Face-to-Face and End Connection Dimensions

Specifies the face-to-face dimensions of wafer, lug, and double-flanged check valves.
Ensures interchangeability between different manufacturers’ valves.
Widely used in industries such as oil & gas, petrochemical, and water treatment.
Applicable pressure classes:
- Class 150, 300, 600, 900, 1500, 2500

2. ASME B16.5 – Pipe Flanges and Flanged Fittings

Defines the dimensions, materials, and pressure ratings for flanges up to 24 inches.
Used to ensure flange compatibility when installing the valve.
Flange pressure classes:
- Class 150, 300, 600, 900, 1500, 2500

3. ASME B16.47 – Large Diameter Steel Flanges

Covers flange sizes from 26 inches to 60 inches.
Used in large-diameter piping systems.

4. EN 558 / ISO 5752 / DIN 3202 – Face-to-Face Dimensions of Valves

European and international standards defining face-to-face dimensions for valves.
These standards ensure compatibility with flanged connections under PN-rated systems.
Pressure ratings: PN 10, 16, 25, 40.

5. EN 1092-1 – Steel Flanges

European standard for flange dimensions, materials, and pressure ratings.
Common pressure ratings: PN 10, 16, 25, 40, 63, 100.

End Connection Types:

Wafer Type:

Designed to fit between two flanges with bolts passing through.
Compatible with multiple flange standards (ASME, EN, JIS, etc.).
Most compact and lightweight connection type.

Lug Type:

Equipped with threaded lugs around the circumference.
Allows the valve to be bolted directly to the flanges, enabling installation at the end of a pipeline.

Double Flanged Type:

Designed with integral flanges for bolted connections on both sides.
Provides more rigid support compared to wafer and lug types.

Summary of Pressure Ratings:

Standard	Pressure Class	Typical Notation
ASME B16.5	150 – 2500	Class 150, 300, etc.
EN 1092-1	PN 10 – PN 100	PN 10, PN 16, etc.
API 594	150 – 2500	Class 150, 300, etc.
JIS B2220	5K – 63K	JIS 10K, 16K, etc.

Electroplating of Single Plate Check Valves

December 11, 2024

Electroplating is a surface treatment process for single-plate check valves that aims to enhance their corrosion resistance, wear resistance, and aesthetic appeal. This process is particularly suited for valves operating in corrosive environments for extended periods. Below is an overview of the electroplating process and key considerations for single-plate check valves:

Common Electroplating Types

Zinc Plating

Features: Economical and practical; suitable for low-corrosion environments.
Applications: Commonly used in indoor or mildly corrosive conditions.

Nickel Plating

Features: Excellent corrosion resistance and decorative finish with a smooth surface.
Applications: Ideal for medium-corrosion environments with higher demands.

Chrome Plating

Features: High wear resistance, hardness, and surface gloss.
Applications: Used in industrial environments with high wear and corrosion.

Zinc-Aluminum Alloy Plating

Features: Combines the advantages of zinc and aluminum for superior corrosion resistance.
Applications: Suitable for harsh environments, such as marine climates or chemical plants.

Multilayer Composite Plating

Features: Combines multiple metal layers to enhance overall performance.
Applications: High-demand scenarios, such as aerospace and marine industries.

Electroplating Process

Pre-treatment

Degreasing: Cleans oil and grease from the surface using an alkaline solution.
Rust Removal: Removes surface rust via acid pickling or mechanical methods.
Surface Activation: Improves plating adhesion.

Electroplating Stage

Primary Electroplating: The valve is placed in an electrolyte solution, where a chemical reaction deposits the metal layer.
Post-Plating Treatment: Includes passivation to enhance corrosion resistance.

Inspection and Post-Treatment

Plating Thickness Check: Ensures the layer meets design specifications.
Appearance Check: Inspects for defects such as bubbles or cracks.
Sealing Treatment: Seals the plating layer to improve corrosion resistance.

Key Considerations

Material Selection
The substrate material of the single-plate check valve must be identified before electroplating. Common materials include cast iron, stainless steel, and carbon steel, which may require different plating processes.

Plating Thickness
Determine the plating thickness based on the operating environment, typically ranging from 5 to 25 microns.

Environmental Compliance
Some electroplating processes involve hazardous substances (e.g., hexavalent chromium). Compliance with environmental regulations is essential, and eco-friendly plating options should be prioritized.

Adhesion Testing
Ensure strong adhesion between the plating and substrate to prevent peeling or flaking.

Corrosion Resistance Testing
Validate the plating’s corrosion resistance through salt spray tests and other methods.

Conclusion

Electroplating significantly improves the service life and performance of single-plate check valves. Selecting the appropriate plating process and ensuring stringent quality control are critical. For customized electroplating solutions, consult a professional surface treatment provider or manufacturer.

Corrosion Prevention Methods for WCB Material Valve Bodies in Marine Valves

December 4, 2024

WCB material (carbon steel castings) is prone to corrosion in certain environments, especially in marine applications. To enhance the service life of WCB valves, effective corrosion prevention methods are necessary. Here are some common approaches:

1. Cathodic Protection

Principle:Install sacrificial anodes (e.g., zinc or magnesium blocks) on the valve body to protect it from corrosion through electrochemical reactions.
Application:Commonly used in seawater pipelines on ships to prevent salt-induced corrosion.

2. Surface Coating Protection

Anti-corrosion Coatings:Apply protective coatings, such as epoxy resin or polyurethane, to the valve surface to create a barrier against corrosive media.
Metallic Coatings:Use thermal spraying to apply a corrosion-resistant metal layer (e.g., aluminum or zinc alloys) on the surface.
Key Requirement:The coating should be uniform, durable, and provide strong adhesion, especially in areas like threads and internal surfaces.

3. Internal Lining with Corrosion-resistant Materials

Method:Line the internal surfaces of the valve with corrosion-resistant materials, such as rubber, fluoroplastics (PTFE), or lead.
Advantages:Directly protects the valve from contact with corrosive media, significantly extending its service life.
Application:Ideal for systems handling highly acidic or alkaline fluids.

4. Application of Anti-rust Oil or Lubricants

Regular Maintenance:Apply anti-rust oil or lubricants to the valve surface, especially for valves that are not in regular use.
Application:Effective in humid or salt-laden environments typical in marine settings.

5. Material Modification or Upgrades

If the environment involves severe corrosion (e.g., sulfur gases, acidic water), WCB material can be treated or upgraded:

Chromium or Nickel Surface Treatment:Enhances oxidation and corrosion resistance.
Use of Alloy Materials:Opt for higher-grade materials like CF8 or CF8M (stainless steel valve bodies) for better performance.

6. Electroplating

Methods:Apply zinc, nickel, or chromium plating to the WCB valve body using electroplating techniques.
Advantages:Provides a dense, wear-resistant, and corrosion-resistant surface with a polished appearance.

7. Environmental Control

Reduce Exposure:Minimize direct contact with high-salinity air or water.
Cleaning and Maintenance:Regularly clean salt, dirt, or corrosive deposits from the valve surface to keep it in optimal condition.

8. Combination of Methods

Coating + Cathodic Protection:Combining surface coatings with cathodic protection can effectively address different types of corrosion and provide comprehensive protection.

Selection Criteria for Corrosion Prevention

Environmental Conditions:Whether the valve is exposed to seawater or acidic/alkaline environments.
Media Type:The corrosiveness of the fluids being handled.
Valve Type and Parts:Different requirements for internal passages and external valve body protection.
Cost-effectiveness:Balancing the cost of corrosion prevention with the expected service life.

In the marine industry, a combination of coatings and cathodic protection is widely used to ensure the durability of WCB material valves. If you have specific application scenarios, the prevention strategy can be further optimized.

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