valve Archives

Concentric type Butterfly Valve Installation Manual

September 12, 2024

Safety Precautions

Isolate the system: Ensure the pipeline is depressurized and drained before installation to avoid hazards.

Wear protective equipment: Always use appropriate personal protective equipment (PPE) like gloves, safety goggles, and hard hats during installation.

Inspect the valve and pipeline: Confirm that both the valve and pipeline are free from debris or foreign material before installation.

Tools and Equipment Required

Torque wrench (to the manufacturer’s specifications)

Gaskets compatible with the pipeline and fluid

Bolts, nuts, and washers (as specified by the valve manufacturer)

Flange alignment tools

Pipe support tools

Pipe cleaning tools (if necessary)

Valve and System Preparation

3.1 Check Valve Condition

Inspect the Valve: Before installation, check the valve for any visible damage, defects, or signs of wear. Ensure the disc operates smoothly by manually rotating it.

Verify Specifications: Make sure that the valve’s pressure, temperature ratings, and material specifications match the system requirements.

3.2 Check Pipeline Compatibility

Flange Condition: Ensure that the flanges on the pipeline are clean, flat, and free of debris. Irregularities in flange surfaces can lead to leakage.

Pipe Alignment: Check that the pipes are correctly aligned. Misaligned pipes can cause the valve to be stressed or damaged during installation.

Installation Steps

4.1 Positioning the Valve

Disc Positioning: Keep the butterfly valve disc in the partially open position (about 10%) during installation. This prevents damage to the seat or disc and ensures easy centering between the flanges.

Mounting Orientation: Ensure the valve is installed with the flow direction indicated by the arrow on the valve body, if applicable. The valve can be installed horizontally or vertically, but ensure enough clearance around the valve for maintenance and operation.

4.2 Placing the Valve Between Flanges

Gasket Installation: Place a gasket between the valve and the flange on both sides. Use gaskets that are suitable for the valve material and the media being handled.

Valve Centering: Carefully place the butterfly valve between the pipeline flanges. The valve must be centered between the flanges to prevent the disc from contacting the inside of the pipe when opening or closing.

4.3 Bolt Tightening Procedure

Insert Bolts: Insert the bolts through the flange holes and the valve’s lugs, if applicable. Hand-tighten all bolts evenly, starting from the center and moving outward in a crisscross pattern.

Cross Pattern Tightening: Use a torque wrench to gradually tighten the bolts in a crisscross pattern to ensure even pressure across the flange surface. Avoid over-tightening to prevent flange distortion or valve damage.

Final Torque: Tighten to the manufacturer’s specified torque value for the bolts. It is important to follow the recommended torque values to avoid leaks or damage to the valve or flanges.

Post-Installation Checks

5.1 Operational Test

Check Valve Operation: Manually operate the valve to ensure that the disc rotates smoothly through its full open and closed positions. There should be no interference with the pipeline.

Leak Testing: After installation, test the valve for leaks by pressurizing the system gradually. Check the valve body, flanges, and gaskets for any signs of leakage.

5.2 Pipeline Support

Support Pipes: Ensure that the pipeline is adequately supported on both sides of the valve. The valve should not bear the weight of the piping, especially for larger installations.

Valve Operation and Maintenance

6.1 Routine Operation

Slow Operation: When operating the valve, do so slowly to avoid water hammer or mechanical shock that could damage the valve or piping system.

Open/Close Position: Ensure the valve is fully closed or fully open during operation, unless being used for flow control.

6.2 Regular Maintenance

Inspection Frequency: Periodically inspect the valve for signs of wear or damage. Pay special attention to the disc, seat, and seals.

Cleaning: If necessary, clean the valve and piping system to remove any buildup that could impair valve performance.

Lubrication: Lubricate moving parts if specified by the manufacturer to ensure smooth operation over time.

Troubleshooting

7.1 Valve Leakage

Potential Causes: Misalignment of the valve, improper torque of the flange bolts, or a damaged gasket.

Solution: Recheck alignment, adjust the bolts according to torque specs, and replace any damaged gaskets.

7.2 Difficulty in Operation

Potential Causes: The valve may have been installed with the disc in contact with the flange or pipe, or debris may be obstructing the disc’s movement.

Solution: Check the installation for alignment issues and clean the pipeline if debris is suspected.

Decommissioning and Removal

Isolate the Valve: Before removing the valve, ensure that the pipeline is depressurized and that the valve is fully closed.

Support the Valve: Ensure the valve is adequately supported during removal, especially for large valves, to prevent injury or damage.

Precautions for Wafer type Connecting Dual Plate Check Valve to the Pipeline

September 3, 2024

When installing a wafer-type dual plate check valve in a pipeline, specific precautions must be observed due to its compact design and the way it interfaces with the piping system. Here are the key precautions:

Correct Orientation:

Ensure that the flow direction matches the arrow indicated on the valve body. Installing the valve in the incorrect orientation can prevent it from functioning correctly and may cause damage.

Centering the Valve:

Properly center the wafer-type valve between the flanges to prevent misalignment. Misalignment can lead to uneven sealing, potential leaks, and difficulty in operation.

Gasket Placement:

Ensure the gaskets are correctly positioned and compatible with the valve and flange materials. They should be centered and not protruding into the valve flow area, as this could obstruct the valve plates and affect operation.

Avoid Over-Tightening Bolts:

Tighten the flange bolts in a crisscross pattern to apply even pressure across the valve. Over-tightening can warp the valve body or damage the gaskets, leading to leaks or operational issues.

Pipeline Support:

The pipeline should be properly supported on either side of the valve to avoid placing excessive weight or stress on the valve, which could affect its alignment and functionality.

Check for Obstructions:

Inspect the pipeline for any debris or foreign objects before installation. Ensure that the valve plates can open and close freely without any obstructions.

Correct Valve Sizing:

Verify that the valve is correctly sized for the specific flow rate and pressure conditions of the system. Using a valve that is too large or too small can lead to poor performance or damage.

Even Flange Face Contact:

Ensure that the flange faces are clean, smooth, and parallel to ensure proper sealing. Uneven flange faces can cause leaks or improper seating of the valve.

Avoiding Thermal and Mechanical Stress:

Avoid installing the valve in areas of the pipeline where it might be subjected to excessive mechanical stress, vibrations, or thermal expansion, which could lead to valve failure.

Hydrostatic Testing:

After installation, conduct a hydrostatic test with the valve fully closed to check for leaks. Make sure the pressure applied during testing does not exceed the valve’s pressure rating.

Proper Tools and Handling:

Use appropriate tools for handling and installing the wafer-type valve. Avoid using excessive force or improper tools, which could damage the valve body or internal components.

Accessibility for Maintenance:

Install the valve in a location that allows for easy access for inspection and maintenance. Wafer-type valves often require periodic checks to ensure they are functioning correctly.

Temperature and Pressure Considerations:

Ensure the valve materials are suitable for the operating temperature and pressure of the system. Avoid subjecting the valve to conditions that exceed its design specifications.

Lubrication (if applicable):

Some wafer-type valves may require lubrication of the hinge pin or other components. Follow the manufacturer’s recommendations for any required lubrication.

By carefully following these precautions, you can ensure a secure, leak-free installation and reliable operation of the wafer-type dual plate check valve in your pipeline system.

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Precautions for Connecting Wafer Butterfly Valve to the Pipeline

August 28, 2024

When connecting a wafer butterfly valve to a pipeline, the following precautions should be taken:

Ensure Proper Alignment: Make sure the valve is correctly aligned between the flanges to avoid any misalignment that could cause leaks or damage to the valve and pipeline.

Check Gasket Positioning: Ensure that gaskets are properly positioned between the valve and flanges to create an effective seal and prevent leakage.

Avoid Over-Tightening Bolts: Tighten the flange bolts evenly in a crisscross pattern to prevent warping of the valve body. Over-tightening can deform the valve or cause the disc to stick.

Disc Position During Installation: Keep the valve disc slightly open during installation to prevent it from contacting the flanges or gaskets, which could damage the disc or interfere with operation.

Verify Compatibility: Ensure the valve’s materials are compatible with the fluid being handled and that the valve’s pressure and temperature ratings match the system requirements.

Pipe Cleanliness: Before installation, clean the pipeline to remove any debris, which could damage the valve seat or disc during operation.

Support the Pipeline: Ensure that the pipeline is properly supported to prevent stress on the valve, which could cause misalignment or leakage.

Flow Direction: Confirm that the valve is installed with the correct flow direction as indicated by the arrow on the valve body.

Final Check: After installation, manually operate the valve to ensure it opens and closes smoothly without obstruction. Conduct a leak test to verify proper sealing.

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/.

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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!

Valve Parameters

August 20, 2024

Nominal Diameter

The nominal diameter (DN) is a numerical designation used to define the size of all piping system components, distinguishing it from those parts that are designated by thread or outside diameter.

Another method for specifying valve sizes is the American system, which uses inches as the unit of measurement. For example, a DN50 valve corresponds to a 2-inch valve.

2.Rounded Numbers

All piping system components with the same nominal pressure (PN) value and the same nominal diameter (DN) have the same connection dimensions that correspond to the type of end connection. In China, when referring to nominal pressure, the unit of measurement is usually specified for clarity and is expressed as “MPa.” In countries like the UK and the US, although the concept of nominal pressure has been included in relevant standards, the imperial unit of pounds per square inch (psi) is still used in practice.

Because the reference temperature for nominal pressure and the pound system differs, there is no strict correlation between them. A general correspondence between them can be found in the table below. The Japanese standard includes a “K” system, such as 10K, 20K, 40K, etc. This pressure rating concept is similar to the pound system in imperial units, but the unit of measurement is metric. The relationship between the “K” rating and the pound system can be found in the table below.

Pressure markings are indicated by “PN” followed by a pressure value (in MPa). For example, PN1.0 indicates a valve with a nominal pressure of 1.0 MPa. However, in everyday use, it is common to refer to a PN10 valve as a 1.0 MPa valve, which is also referred to as a 10 bar/10 kg valve.

3. Common Unit Conversion Relationships

1 inch = 25.4 mm

1 MPa = 10 kgf/cm² (kilogram-force) = 10 bar

1 psi = 0.0069 MPa

1 ksi = 6.9 MPa

Psi: pounds per square inch

kgf/cm²: kilogram-force per square centimeter

Bar: bar

Fahrenheit to Celsius Conversion:

°C = (℉ – 32) * 5/9

Celsius to Fahrenheit Conversion:

℉ = ℃ * 9/5 + 32

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!

Application of Single Door Check Valve

July 17, 2024

A single door check valve, also known as a swing check valve, is used in various applications to allow fluid (liquid or gas) to flow in one direction only and prevent backflow.

ALB Single plate check valve

Wafer stainless steel swing check valve

Here are some common applications:

Water Supply Systems:

To prevent backflow in municipal water supply systems.

In residential plumbing to stop contaminated water from re-entering the clean water supply.

Pumping Systems:

To prevent backflow when the pump is turned off, protecting the pump and avoiding reverse flow that could cause damage.

In sump pump systems to prevent water from flowing back into the sump pit.

Oil and Gas Industry:

In pipelines to ensure one-way flow of oil or gas, preventing backflow that could cause contamination or pressure issues.

In offshore platforms to prevent reverse flow of sea water.

HVAC Systems:

In heating, ventilation, and air conditioning systems to control the direction of refrigerant flow.

In cooling towers to prevent backflow of water.

Chemical Processing:

To ensure the correct flow of chemicals in process lines, preventing contamination and ensuring safe operation.

In acid and alkali handling systems to avoid backflow which could cause reactions or damage.

Marine Applications:

In bilge systems to prevent water from flowing back into the bilge area.

In ballast systems to control the flow of water in and out of ballast tanks.

Fire Protection Systems:

In fire sprinkler systems to ensure water flows in one direction and to prevent backflow which could cause contamination or loss of pressure.

Key Features and Considerations

Non-return function: Prevents reverse flow automatically.

Low-pressure drop: Designed to minimize resistance to flow.

Reliability: Robust and simple design ensures long-term, reliable operation.

Material: Made from various materials like stainless steel, brass, and plastic, depending on the application and fluid type.

Size and Pressure Rating: Available in various sizes and pressure ratings to suit different applications and flow rates.

These valves are essential in systems where maintaining a unidirectional flow is critical for safety, efficiency, and system integrity.

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/

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Standards for Use of Marine Valves

July 9, 2024

Specifies dimensions for metal valves used in marine applications.

butterfuly valve manufacturer

Classification Societies

Classification societies provide additional guidelines and standards specific to marine applications. Some of the major classification societies include:

American Bureau of Shipping (ABS):

ABS Rules for Building and Classing Marine Vessels: Includes requirements for the design, construction, and testing of valves used in marine vessels.

Lloyd’s Register (LR):

Rules and Regulations for the Classification of Ships: Contains specific sections on the requirements for marine valves, including materials, design, and testing.

Bureau Veritas (BV):

Rules for the Classification of Steel Ships: Provides guidelines on the use of valves in marine applications, including specifications for materials and testing.

Det Norske Veritas (DNV):

DNV Rules for Classification of Ships: Outlines the requirements for valves used in marine systems, covering aspects such as design, materials, and performance testing.

National Standards

Different countries may have their own standards and regulations for marine valves. Some notable examples include:

ASTM (American Society for Testing and Materials):

ASTM F1199: Standard Specification for Ferrous Valves for Shipboard Use – Covers the requirements for ferrous valves used on ships.

BS (British Standards):

BS 6364: Valves for cryogenic service – Specifies the requirements for valves used in cryogenic applications, which can be relevant for certain marine applications.

Key Considerations for Marine Valves

Corrosion Resistance: Materials used for marine valves must be highly resistant to corrosion due to exposure to seawater and harsh marine environments.

Pressure and Temperature Ratings: Valves must be able to withstand the specific pressure and temperature conditions encountered in marine systems.

Safety and Reliability: Ensuring that valves operate reliably under the dynamic conditions of marine environments is crucial for safety.

Maintenance and Inspection: Valves should be designed for ease of maintenance and inspection, considering the limited access and challenging conditions on marine vessels.

Compliance and Certification: Marine valves should comply with relevant standards and regulations, and obtaining certification from recognized classification societies is often required.

By adhering to these standards and guidelines, marine valves can provide safe, reliable, and efficient performance in various marine applications, ensuring the safety and operational integrity of marine vessels and structures.

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!

Design standards and materials for single door check valves

July 2, 2024

Design Standards for Single Door Check Valves

Single door check valves are designed and manufactured according to various international standards to ensure quality, reliability, and compatibility. Some of the common standards include:

API 594: Covers the requirements for check valves, including design, manufacturing, testing, and inspection.

ASME B16.34: Provides standards for pressure-temperature ratings, dimensions, and materials for valves.

ISO 5752: Standardizes face-to-face and end-to-end dimensions of valves.

BS 1868: Specifies requirements for check valves for petroleum, petrochemical, and allied industries.

DIN 3202: Specifies face-to-face dimensions for valves used in piping systems.

Common Materials Used in Single Door Check Valves

The selection of materials for single door check valves depends on the application, including the type of fluid, operating temperature, and pressure. Common materials include:

6 single-plate-swing-check-valve-2

Body Materials:

Stainless Steel (e.g., 304, 316): Offers excellent corrosion resistance and strength, suitable for a wide range of applications, including aggressive fluids.

Carbon Steel: Provides good strength and durability, commonly used in water, oil, and gas

applications.

Ductile Iron: Combines good strength and impact resistance, often used in water and wastewater applications.

Bronze: Good corrosion resistance, commonly used in marine and potable water applications.

single disc swing check valve body

Stainless Steel: For applications requiring high corrosion resistance.

Carbon Steel: Used for general-purpose applications.

Bronze: Commonly used in applications involving seawater or drinking water.

Composite Materials: Such as reinforced plastics for lightweight and corrosion-resistant applications.

Seat Materials:

Metal Seats (e.g., stainless steel, bronze): Durable and can withstand high temperatures and pressures.

Soft Seats (e.g., EPDM, NBR): Provide better sealing and are used in applications where tight shutoff is required, typically at lower temperatures and pressures.

Spring Materials (if applicable):

Stainless Steel: Commonly used for springs due to its good corrosion resistance and mechanical properties.

Inconel: For high-temperature applications requiring superior strength and corrosion resistance.

Considerations for Material Selection

Corrosion Resistance: Ensure the material can withstand the fluid’s chemical properties.

Temperature and Pressure: The material must be able to handle the operating conditions without degrading.

Mechanical Properties: The material should have the necessary strength and durability for the application.

Regulatory Compliance: Ensure materials meet any regulatory or industry standards required for the application.

By selecting appropriate materials and adhering to design standards, single door check valves can provide reliable and long-lasting performance in a variety of industrial 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!

The Application of Concentric Type Butterfly Valve in Petroleum(oil and gas) Industry

June 25, 2024

Concentric type butterfly valves play vital roles across various sectors within the petroleum (oil and gas) industry due to their reliability, versatility, and cost-effectiveness. Here are the main applications of concentric type butterfly valves in the petroleum industry:

Flow Control in Pipeline Systems:

Crude Oil Pipelines: Regulating the flow of crude oil within pipelines during transportation from production fields to refineries or terminals.

Natural Gas Pipelines: Controlling the flow of natural gas in transmission and distribution pipelines.

Refined Product Pipelines: Managing the flow of refined petroleum products like gasoline, diesel, and jet fuel.

Wellhead and Production Systems:

Flow Control: Regulating the flow of crude oil, natural gas, or water at wellheads and production facilities.

Water Injection Systems: Controlling the injection of water for secondary or tertiary oil recovery methods.

Refining Processes:

Cooling Systems: Regulating the flow of cooling water for heat exchangers and condensers.

Process Fluids: Controlling the flow of various process fluids during refining operations.

Chemical Injection Systems: Regulating the flow of chemicals for process treatment and corrosion inhibition.

Storage Terminal Operations:

Tank Farm Operations: Handling the flow of crude oil, refined products, and

chemicals within storage tank farms.

Loading and Unloading: Controlling the flow of petroleum products during loading onto tankers and unloading from ships or trucks.

Offshore Platforms and Floating Production Systems:

Seawater Systems: Regulating seawater flow for cooling, firewater, and other offshore operations.

Ballast Systems: Controlling ballast water for stability adjustment on offshore platforms.

Firewater Systems: Emergency firefighting systems on offshore platforms.

Petrochemical Plants:

Feedstock Handling: Controlling the flow of feedstocks such as ethylene, propylene, and other petrochemical products.

Process Fluids: Regulating the flow of various chemicals and fluids during production processes.

Key Advantages in the Petroleum Industry:

Corrosion Resistance: Materials selected are often resistant to corrosion from petroleum products and chemicals.

Space Efficiency: Compact design is suitable for installations where space is limited, such as offshore platforms.

Quick Operation: Rapid open/close operation for emergency shutdown situations.

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

Cost-Effective Solution: Butterfly valves offer cost savings compared to other valve types.

Concentric type butterfly valves are indispensable components in the petroleum industry, serving critical functions in transportation, production, refining, storage, and distribution of oil and gas products. Their versatility, reliability, and cost-effectiveness make them widely used in various applications throughout the industry. Proper selection, installation, and maintenance of these valves are essential to ensure safe and efficient operations in the petroleum sector.

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 valves in the shipbuilding industry（tanghai Valve)

June 7, 2024

Marine valves play a crucial role in shipbuilding, managing the flow of various fluids such as water, fuel, oil, and gases throughout a vessel. These valves are essential for the operational efficiency, safety, and maintenance of a ship. Here are some common types of marine valves used in shipbuilding and their functions:

Gate Valves

Function: Used for on/off control of fluids.

Application: Often used in systems where the valve remains either fully open or fully closed, such as in ballast and bilge systems.

Globe Valves

Function: Used for regulating flow and pressure.

Application: Typically found in cooling water, fuel oil, and lubricating oil systems where flow needs to be controlled.

Ball Valves

Function: Provide tight shut-off and control flow.

Application: Commonly used in low-pressure systems like potable water and compressed air.

Butterfly Valves

Function: Regulate or isolate flow with a rotating disc.

Application: Used in large diameter pipes, such as those in ballast systems, due to their compact design and lightweight.

Check Valves

Function: Prevent backflow.

Application: Installed in bilge lines, ballast systems, and various other systems to ensure one-way flow of fluids.

Safety Relief Valves

Function: Protect systems from overpressure.

Application: Essential in steam systems, hydraulic systems, and any pressurized tanks to release excess pressure.

Control Valves

Function: Regulate flow, pressure, temperature, and level.

Application: Used in automated systems for precise control, often integrated with sensors and actuators.

Diaphragm Valves

Function: Control flow with a flexible diaphragm.

Application: Suitable for corrosive or abrasive fluids, often found in sanitary or chemical systems.

Materials Used

Marine valves must withstand harsh marine environments, including exposure to saltwater, chemicals, and varying temperatures. Common materials include:

Bronze: Excellent corrosion resistance, commonly used for smaller valves.

Brass: Good corrosion resistance and machinability.

Stainless Steel: High strength and corrosion resistance, used in more demanding applications.

Cast Iron: Durable and cost-effective for non-corrosive applications.

Ductile Iron: Offers more strength and flexibility compared to cast iron.

Installation and Maintenance

Installation: Proper installation ensures the longevity and functionality of marine valves. This includes correct orientation, secure mounting, and adherence to manufacturer specifications.

Maintenance: Regular inspections, cleaning, and lubrication are crucial. Valves should be checked for leaks, corrosion, and proper operation. In high-wear applications, routine part replacement might be necessary.

Regulatory Standards

Marine valves must comply with international and national maritime regulations to ensure safety and performance. Key regulatory bodies include:

International Maritime Organization (IMO)

American Bureau of Shipping (ABS)

Lloyd’s Register (LR)

Det Norske Veritas (DNV)

Bureau Veritas (BV)

In summary, marine valves are integral components in shipbuilding, ensuring the safe and efficient operation of various ship systems. Their selection, installation, and maintenance are vital for the vessel’s overall performance and safety.

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!

Dual plate check valve in marine valve

June 1, 2024

A double plate check valve, also known as a dual plate check valve or wafer check valve, is a type of non-return valve commonly used in various fluid systems on ships. It is designed to allow fluid to flow in one direction while preventing backflow, ensuring that the fluid flow is unidirectional. Here are some key features and details about double plate check valves used in ship valves:

Key Features of Double Plate Check Valves

1,Dual Plates: The valve has two spring-loaded plates or discs that open when fluid flows in the desired direction and close when there is a reversal of flow. This design ensures a quick response to changes in flow direction.

2,Wafer Type Design: These valves have a compact and lightweight wafer design, making them easy to install between flanges in a pipeline. They occupy less space compared to other types of check valves.

3,Non-Slam Closure: The spring-loaded mechanism ensures a non-slam closure, reducing the risk of water hammer, which can cause damage to the piping system.

4,Low Pressure Drop: The dual plate design offers minimal resistance to flow, resulting in a low-pressure drop across the valve.

5,Material Options: These valves are available in various materials such as stainless steel, cast iron, and other alloys to suit different types of fluids and environmental conditions, including seawater applications.

6,Versatility: Suitable for a wide range of applications including ballast systems, cooling systems, fuel systems, and bilge systems on ships.

Advantages in Marine Applications

1,Space-Saving: The compact design is particularly advantageous in the confined spaces typically found in marine engine rooms and other shipboard locations.

2,Durability: Marine environments are harsh, and the materials used in these valves are selected for their corrosion resistance and durability.

3,Maintenance: Double plate check valves are designed for easy maintenance, which is critical in marine operations where downtime needs to be minimized.

4,Efficiency: By preventing backflow and ensuring a unidirectional flow, these valves contribute to the efficiency and reliability of the ship’s fluid systems.

Common Uses on Ships

Ballast Water Systems: Ensuring the correct flow direction in ballast water management, crucial for the stability and balance of the ship.

Cooling Water Systems: Used in engine cooling systems to ensure the proper flow of seawater or freshwater for cooling purposes.

Fuel Systems: Preventing backflow in fuel lines, which is critical for the safe and efficient operation of ship engines.

Bilge Systems: Ensuring the proper discharge of bilge water and preventing backflow into the bilge.

Installation and Maintenance Tips

Proper Alignment: Ensure the valve is correctly aligned with the flow direction indicated on the valve body during installation.

Regular Inspection: Periodic inspection and maintenance are essential to ensure the valve operates correctly and to prevent potential failures.

Material Compatibility: Select the appropriate material for the valve based on the specific application and the type of fluid being handled to avoid corrosion and other issues.

In summary, double plate check valves are a critical component in shipboard fluid systems, providing reliable performance, efficiency, and ease of maintenance, which are essential for the safe and effective operation of maritime vessels.

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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