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Concentric type Butterfly Valve with Ductile Iron Body and Bronze Disc

September 26, 2024

A Concentric Type Butterfly Valve with a Ductile Iron Body and Bronze Disc is a reliable and versatile valve used for controlling fluid flow in various applications. Here’s a breakdown of its features:

Key Features:

Body Material: Ductile Iron

Ductile iron is a strong and durable material with excellent mechanical properties, including good tensile strength, flexibility, and resistance to cracking. It is preferred over cast iron due to its enhanced toughness.

Ideal for medium-pressure applications, ductile iron can withstand significant stress and offers long-term durability in harsh environments.

Disc Material: Bronze

Bronze is known for its superior corrosion resistance, particularly in water-based systems, and is often chosen for its ability to handle a wide range of fluids, including water, oil, and steam.

A bronze disc ensures smooth operation and longer service life in environments where metal-to-metal wear or corrosion could be a concern.

Concentric Design

In a concentric butterfly valve, the disc and the stem are centrally aligned. This provides a uniform sealing surface and is typically used in low- to medium-pressure systems.

The disc is centered within the valve body, and the valve opens and closes by rotating the disc 90 degrees on a shaft.Sealing Mechanism

Concentric butterfly valves typically use a resilient seat (like EPDM or NBR) that presses against the bronze disc to create a tight seal, preventing leaks.

Operation

This valve can be manually operated with a lever or gear mechanism or automated using pneumatic or electric actuators.

Common Applications:

Water Treatment and Distribution: Suitable for potable water, sewage, and wastewater systems.

HVAC Systems: Used for regulating flow in heating and cooling systems.

Irrigation Systems: Controls water flow in agricultural irrigation.

General Industrial Processes: Can be used in chemical, petrochemical, and other industrial applications where corrosion resistance is essential.

Advantages:

Cost-effective: The combination of ductile iron and bronze makes this type of valve both affordable and reliable.

Corrosion Resistance: The bronze disc ensures superior resistance to corrosion, particularly in water and steam applications.

Ease of Maintenance: Simple design allows for easy maintenance and repair.

This valve is a practical choice for a variety of fluid control systems due to its durability, ease of operation, and resistance to harsh environments.

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!

Maintenance of the Concentric type Butterfly Valve in Ships

September 19, 2024

The maintenance of a concentric (centered) butterfly valve in ships is essential to ensure the valve’s optimal performance and longevity, especially in harsh marine environments. Concentric butterfly valves have the disc located in the center of the valve body, with a resilient seat that helps to seal the valve when closed. These valves are commonly used for fluid control in various ship systems, including seawater cooling, ballast systems, and bilge systems. Here’s a guide to maintaining a concentric butterfly valve on ships:

Visual Inspection

External Inspection:Regularly check the valve for any visible signs of corrosion, wear, or damage, especially around the body, stem, and handle or actuator.

Marine environments are prone to corrosion due to saltwater, so special attention should be given to areas exposed to seawater.

Inspect for any salt deposits, marine growth, or other debris that may accumulate around the valve body and flanges.

Seal Inspection:Inspect the valve’s seat (usually made of rubber or elastomer) for wear or damage. The seal is crucial for the valve’s tight closure.

Check for cracks, deformities, or wear in the seal that could lead to leakage. The seal is one of the most critical parts, and its condition directly affects valve performance.

Regular Cleaning

Valve Cleaning:Clean the exterior and interior of the valve regularly to remove any buildup of marine organisms, rust, silt, or debris that may impair its function.

Use approved marine cleaning agents that do not damage the valve’s materials. After cleaning, thoroughly rinse the valve with freshwater to remove any residual chemicals.

Seal and Disc Cleaning:Gently clean the valve’s disc and seat to remove any deposits. Marine organisms, like barnacles or algae, can settle on the disc, potentially impacting valve closure.

Lubrication

Stem and Moving Parts:

Lubricate the stem and other moving parts of the valve as per the manufacturer’s recommendations. Marine-grade lubricants should be used to prevent corrosion and ensure smooth operation.

Avoid over-lubricating, as excess lubricant can attract dirt or debris.

Actuator Lubrication (for automated valves):

If the valve is equipped with an actuator (pneumatic, hydraulic, or electric), ensure that the actuator’s moving parts are adequately lubricated. Regularly check actuator connections to ensure they are secure and functioning smoothly.

Operational Testing

Open and Close Testing:Periodically operate the valve by fully opening and closing it to ensure the disc moves freely. A valve that isn’t operated regularly may become stiff or difficult to operate due to corrosion, buildup, or seal hardening.

Ensure that there are no sticking points, and check the valve handle or actuator for any issues.

Leakage Testing:Perform a hydrostatic or pneumatic test at operating pressure to detect any leaks. If leakage is found, inspect the seat, seal, and disc for damage.

For valves under critical operation (e.g., seawater intake or discharge), this test should be part of routine inspections.

Seal Replacement

Seal and Seat Maintenance:

The resilient seat is a key component that provides a bubble-tight seal in a concentric butterfly valve. Over time, the seat can wear out or become damaged due to constant use or exposure to chemicals, requiring replacement.

Replace the valve seat if you notice signs of cracking, deformation, or excessive wear that could compromise its sealing ability.

Stem Seals:

Inspect the stem seals (o-rings or gaskets) for wear. If these seals fail, it could lead to leakage around the stem area.

Corrosion Protection

Protective Coating:

Apply protective coatings, like marine-grade anti-corrosive paints, to the external parts of the valve that are exposed to saltwater or humid environments.

If the valve is made from a material prone to rust (such as certain grades of cast iron), extra attention should be given to keeping the body protected from corrosion.

Material Compatibility:

Ensure that the valve material (body and disc) is suitable for the specific fluid or gas being handled. Corrosion-resistant materials like stainless steel or bronze should be used for seawater applications.

Actuator and Control System Maintenance

Actuator Inspection:

For automatic valves, inspect the actuator system regularly. Check for signs of wear, corrosion, or malfunction in the actuator.

Ensure the actuator’s control signals are accurate, and the valve opens and closes fully when triggered.

Control System Calibration:

If the valve is part of an automated control system, periodically calibrate the system to ensure it operates at the correct parameters (e.g., pressure or flow settings).

Bolts and Flange Check

Tightness of Flange Bolts:Periodically check the tightness of the bolts securing the valve to the pipe flanges. Marine vibrations can loosen these bolts over time.

Use the manufacturer-recommended torque settings when tightening bolts to avoid over-tightening or damaging the valve body.

Gasket Inspection

Flange Gasket:Check the condition of flange gaskets between the valve and pipe flanges. If leaks are detected, the gasket may need to be replaced.

Gaskets exposed to high pressure, temperature, or aggressive fluids might degrade faster and require more frequent replacement.

Summary of Key Maintenance Practices:

Regular inspection: Visual and operational checks for corrosion, leaks, and damage.

Cleaning: Routine cleaning of valve components to remove marine growth and deposits.

Lubrication: Ensure moving parts are lubricated using marine-grade products.

Seal and gasket maintenance: Inspect and replace the valve seat, stem seals, and flange gaskets as needed.

Operational tests: Open and close the valve to ensure smooth operation.

Corrosion protection: Apply anti-corrosion coatings and ensure material compatibility with seawater.

Maintenance Schedule:

Weekly: Visual inspections, operational testing, and cleaning of external surfaces.

Monthly: Internal cleaning, actuator system checks, and lubrication.

Annually: Comprehensive inspections, including seal, gasket, and bolt checks; perform leakage tests and replace worn-out components.

Maintaining concentric butterfly valves on ships is crucial for ensuring the reliability of fluid systems, preventing leaks, and extending the valve’s service life.

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!

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.

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!

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/.

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!

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 Concentric type Resilient Seated Butterfly Valve in Marine Vessel

August 13, 2024

Concentric type resilient seated butterfly valves are commonly used in marine vessels for several reasons:

Leakage Prevention: The resilient seat provides a tight seal, reducing the risk of leakage in critical applications. This is crucial in marine environments where leaks can lead to significant safety and operational issues.

Corrosion Resistance: These valves are often made from materials that resist corrosion, which is essential for marine applications due to the harsh saltwater environment.

Compact Design: The concentric design allows for a compact and lightweight valve, which is beneficial in the space-constrained environment of a marine vessel.

Ease of Operation: These valves generally have a simple design that makes them easy to operate, which is important for maintaining efficient and reliable operation on a vessel.

Flow Control: They provide effective flow control, which is necessary for managing various systems on a marine vessel, such as cooling systems, ballast systems, and fuel systems.

Maintenance: The design typically allows for easier maintenance and replacement, which is advantageous for keeping the vessel in good working condition.

The concentric type resilient seated butterfly valve is valued in marine applications for its reliability, resistance to corrosion, and ease of maintenance, all of which contribute to the safe and efficient operation of marine 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!

Classification of valve

August 5, 2024

There are many types of valves, and they can be classified in various ways.

Classification by automation and actuation

Automatic Valves: These valves operate automatically relying on the medium (liquid, gas, steam, etc.) itself. Examples include safety valves, check valves, pressure reducing valves, and automatic exhaust valves.

Actuated Valves: These valves are operated manually, electrically, hydraulically, or pneumatically. Examples include butterfly valves, gate valves, and ball valves.

II.Classification by purpose and function

Shut-off Valves: Primarily used to stop or start the flow of the medium. This includes gate valves, globe valves, plug valves, ball valves, butterfly valves, etc.

Regulating Valves: Primarily used to regulate the flow, pressure, etc., of the medium. This includes control valves, throttle valves, pressure reducing valves, etc.

Check Valves: Used to prevent the backflow of the medium. This includes various types of check valves.

Diverting Valves: Used to distribute, separate, or mix the medium. This includes various types of distribution valves, three-way valves, and steam traps.

Safety Valves: Used for overpressure safety protection, releasing excess medium to prevent pressure from exceeding the specified value. Examples include safety valves.

Multi-function Valves: Used to replace two, three, or more types of valves, such as globe check valves, check ball valves, etc.

Other Special Valves: Examples include drain valves, pigging valves, etc.

III. Classification by main parameters

1, Classification by nominal diameter The nominal diameter is a rounded integer value used as a convenient reference to indicate the valve size. It is an approximate value rather than an exact measurement. The nominal diameter is marked with the letters “DN” (nominal diameter) followed by a value in millimeters. For example, a valve with a nominal diameter of 50 millimeters is marked as DN50.

Small diameter valves: Valves with DN≤40mm
Medium diameter valves: Valves with DN50-DN300mm
Large diameter valves: Valves with DN350-DN1200mm (4) Extra-large diameter valves: Valves with DN≥1400mm

2, Classification by pressure Nominal pressure refers to the design-specified pressure related to the mechanical strength of the pipeline components. The pressure is marked with “PN” followed by a pressure value (MPa). For example, PN1.0 indicates a valve with a nominal pressure of 1.0 MPa. (1) Vacuum valves: Valves with a working pressure lower than standard atmospheric pressure. (2) Low-pressure valves: Valves with a nominal pressure of PN<1.6 MPa. (3) Medium-pressure valves: Valves with a nominal pressure of PN 2.5–6.4 MPa. (4) High-pressure valves: Valves with a nominal pressure of PN 10.0–80.0 MPa. (5) Ultra-high-pressure valves: Valves with a nominal pressure of PN≥100 MPa.

3, Classification by working temperature of the medium (1) High-temperature valves: Valves with t > 450℃ (2) Medium-temperature valves: Valves with 120℃ ≤ t < 450℃ (3) Normal-temperature valves: Valves with -40℃ ≤ t < 120℃ (4) Low-temperature valves: Valves with -100℃ ≤ t < -40℃ (5) Ultra-low-temperature valves: Valves with t < -100℃

4, Classification by valve body material (1) Non-metallic material valves: Such as ceramic valves, fiberglass valves, plastic valves (2) Metallic material valves: Such as copper alloy valves, Monel alloy valves, cast iron valves, carbon steel valves, alloy steel valves (3) Metal body lined valves: Such as lead-lined valves, plastic-lined valves, enamel-lined valves.

5, Classification by connection method to the pipeline (1) Flange connection valves: Valves with flanges on the body, connected to the pipeline using flanges. (2) Threaded connection valves: Valves with threads on the body, connected to the pipeline using threads. (3) Welded connection valves: Valves with weld ends on the body, connected to the pipeline using welding. (4) Clamp connection valves: Valves with clamps on the body, connected to the pipeline using clamps. (5) Ferrule connection valves: Valves connected to the pipeline using ferrules.

III. Common Classification This classification method is based on principle, function, and structure and is the most commonly used classification method domestically and internationally. It generally includes gate valves, globe valves, plug valves, ball valves, butterfly valves, diaphragm valves, check valves, throttle valves, safety valves, pressure reducing valves, steam traps, and control valves.

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/

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!

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!

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