How To Select J-VALVES Check Valves Based on Characteristics, Applications And Quality

I. Analysis of the Characteristics of J-VALVES Check Valves

(A) Structural Characteristics

• Swing Type: The valve disc rotates around the pin shaft outside the valve seat, featuring a simple structure, good sealing performance and low fluid resistance. It has a large opening height and is suitable for large-diameter and high-flow applications. However, it is relatively large in size and requires a high installation space.

• Lift Type: The valve disc moves along the vertical central line of the valve body. It has a compact structure and reliable sealing performance. Nevertheless, the resistance of the fluid passing through is relatively large, and it is generally suitable for small-diameter and low-flow pipeline systems.

• Butterfly Type: The valve disc is in the shape of a butterfly and is opened and closed by rotation. It has a quick opening and closing speed and is convenient to operate. With a simple structure, small size and light weight, its sealing performance is relatively poor and it is mostly used in occasions where the sealing requirement is not high.

• Pipeline Type: The valve body is in the shape of a straight pipeline, with low fluid resistance and convenient installation. It can be directly installed on the pipeline, saving space. However, its sealing performance and pressure resistance are relatively weak.

(B) Characteristics of Working Principle

• Driven by Fluid Pressure: Most J-VALVES check valves are driven by the pressure of the fluid itself to open or close the valve disc. When the fluid flows forward, the fluid pressure overcomes the spring force or gravity to open the valve disc. When the fluid stops flowing or flows backward, the valve disc closes under the action of the spring force, gravity or the reverse fluid pressure, thus preventing the fluid from flowing backward.

• With Slow Closing Function: Some J-VALVES check valves are designed with slow closing devices, such as damping springs. This design enables the valve disc to quickly close a part first and then slowly close the remaining part during the closing process, effectively avoiding the water hammer phenomenon caused by the rapid closing of the valve disc and protecting the pipeline system from the damage of water hammer impact.

II. Application Scenarios of J-VALVES Check Valves

(A) Applications in Different Industries

• Petrochemical Industry: In the oil and gas transmission pipelines, as well as the inlet and outlet pipelines of various reactors, towers and other equipment in the chemical production process, J-VALVES check valves are often used to prevent the backflow of media and avoid safety accidents caused by backflow, such as media mixing and equipment damage. For example, in the oil refining process, it is used to prevent crude oil from flowing back into the pump when the pump stops during the transmission process, thus avoiding damage to the pump.

• Power Industry: In the cooling water systems and feed water systems of power plants, check valves are used to ensure the one-way flow of water and prevent water from flowing backward, which may lead to insufficient equipment cooling or abnormal pressure in the feed water system. Meanwhile, in the steam pipeline system, they are also used to prevent the backflow of steam and ensure the normal operation of equipment.

• Municipal Water Supply and Drainage Industry: In urban water supply networks, sewage treatment plants and other places, check valves are used to prevent the backflow of water, avoid sewage from flowing back to pollute clean water, or prevent water from flowing backward to damage water pumps and other equipment after the pump stops. For example, the check valve installed at the outlet of the water pump in the urban water supply pipeline can prevent water from flowing back into the pump when the pump stops and protect the water pump from water hammer impact.

• Food and Pharmaceutical Industry: In the pipeline systems with high hygiene requirements in food processing and pharmaceutical production, such as beverage production lines and liquid medicine transmission pipelines, hygienic J-VALVES check valves are adopted to prevent the backflow of materials and avoid pollution, ensuring product quality and production safety.

(B) Applications in Different Working Conditions

• High Temperature and High Pressure Working Conditions: For pipeline systems working in high temperature and high pressure environments, such as steam pipelines and high-temperature medium transmission pipelines in the petrochemical industry, J-VALVES check valves that are resistant to high temperature and high pressure should be selected. These valves are usually made of high-temperature alloy steel and other materials and equipped with high-temperature-resistant seals to ensure reliability and sealing performance under harsh working conditions.

• Low Temperature Working Conditions: In the low-temperature medium transmission pipelines, such as liquefied natural gas (LNG) pipelines, check valves need to have good low-temperature performance. Their materials and seals should be able to maintain good toughness and sealing performance at low temperatures to prevent medium leakage or backflow caused by material embrittlement or seal failure.

• Corrosive Medium Working Conditions: When corrosive media such as acid, alkali and salt solutions are transported in the pipeline, J-VALVES check valves should be made of materials with strong corrosion resistance, such as stainless steel, alloy steel, plastics, etc., and corrosion-resistant sealing materials, such as polytetrafluoroethylene (PTFE), rubber, etc., to prevent the valves from being corroded and damaged and ensure their normal operation.

• High Flow Velocity Working Conditions: In pipeline systems with high fluid flow velocity, the fluid resistance and sealing performance of check valves are particularly important. Check valves with low fluid resistance and reliable sealing performance, such as swing type check valves, should be selected to reduce fluid energy loss and ensure that they can still effectively prevent fluid backflow under high flow velocity.

Different types of J-VALVES check valves are suitable for different application scenarios. Selecting the appropriate type of check valve is crucial for the normal operation of the system. The following is a comparison of several common application scenarios:

III. Quality Evaluation of J-VALVES Check Valves

• Valve Body Material: The valve body is the main component of the check valve, and its material should have sufficient strength, toughness and corrosion resistance. Common valve body materials include cast iron, cast steel, stainless steel, alloy steel, etc. Cast iron valve bodies are suitable for occasions with low pressure, moderate temperature and weak corrosiveness. Cast steel valve bodies have high strength and are suitable for medium and high-pressure pipeline systems. Stainless steel valve bodies have good corrosion resistance and are suitable for pipeline systems transporting corrosive media. Alloy steel valve bodies can be used in special working conditions such as high temperature and high pressure.

• Valve Disc Material: The valve disc is a key component of the check valve, and its material should have good wear resistance, corrosion resistance and sealing performance. It is usually made of the same or higher-grade materials as the valve body, such as stainless steel, alloy steel, etc. For some special working conditions, hard alloy and other materials can also be used to improve the wear resistance and service life of the valve disc.

• Sealing Material: The quality of the sealing material directly affects the sealing performance of the check valve. Commonly used sealing materials include rubber, polytetrafluoroethylene (PTFE), metal seals, etc. Rubber seals have good elasticity.