What is A Check Valve ?

- The check valve is installed on the pipeline system with the function of allowing the refrigerant flow to go in only one direction, preventing the back flow to ensure the operation of the equipment on the pipeline, preventing loss. of the medium in the event of a leak or breakdown.

Types of Check Valves

• Structure and Operation of Check Valves

- Swing Check Valve

+ A type of valve with a valve disc attached to the valve shaft in the form of a hinge, when there is flow into the valve, the valve disc is flipped up to allow flow to pass, and similarly when the flow is cut off, the valve disc flips down to prevent flow. reverse flow.

+ Cover of Swing Check Valve : Designed for convenient inspection and maintenance of the valve.

+  Body of Swing Check Valve : connected to the pipeline through threaded and flanged connections. The valve body protects the components installed in the valve.

+  Shaft of Swing Check Valve: connection between the valve disc and the inner body of the valve, connecting to the valve body according to the bolt connection, and connecting to the valve disc in the form of a hinge

+  Disc of Swing Check Valve: connected to the valve shaft through a hinge connection, which helps the valve disc flip up and down to open and close the flow.

+ When there is pressure, the flow enters the valve at this time, the valve gate will be flipped up and let the flow through. When the flow is cut off, the push pressure is lost, the weight of the vane will make the vane flip down to close, when the flow is cut off, it will prevent the reverse flow.

- Lift Check Valve

+ The lift check valve is also known as the reciprocating check valve and the steam check valve. The valve opens and closes thanks to the weight of the disc moving along the valve shaft and the return pressure of the refrigerant in the pipeline system causing the disc to close.

+ Cover of Lift Check Valve: Convenient design for convenient inspection, maintenance and cleaning of the valve

+ Body of Lift Check Valve: Connects to the pipeline through threaded and flanged connections. The valve body protects the components installed in the valve.

+ Disc of Lift Check Valve: Direct contact with the medium to perform the task of opening and closing the valve.

+ When there is refrigerant flow entering the valve in the direction of the arrow, the pressure of the refrigerant flow overcomes the force of the spring that compresses the disc upwards allowing the refrigerant to pass through the valve. And vice versa, when the fluid is cut off, the flow pressure cannot overcome the compression force of the spring, so the valve is closed.

- Spring Check Valve

+ Spring check valve has a disc and spring fixed in the valve body. The valve works by means of the compression and elastic force of the spring to allow lip flow through the valve.

+ Body of Spring check valve: Connects to the pipeline through threaded and flanged connections. The valve body protects the components installed in the valve.

+ Spring of Spring check valve: Holds the valve disc tightly closed to the disc to prevent the refrigerant from flowing back thanks to the elastic force of the spring.

+ Shaft of Spring check valve: The connection between the spring and the bottom of the valve, helping the spring to stay in place.

+ Disc of Spring check valve: Direct contact with the medium has a circular shape, responsible for opening and closing the flow

+ When the fluid flows into the valve, under the pressure of the flow, the force of the spring is applied, the spring is compressed, the valve disc is pushed up from the closed position of the valve, and the fluid is allowed to pass through the valve. When the flow stops, there will be two sources of pressure: pressure, the pressure of the reverse flow, and the elastic force of the spring to help the valve disc return to the closed position to prevent the reverse flow.

- Butterfly Check Valve Wafer Style

+ As a valve with a vane structure consisting of two butterfly-shaped flap discs, it is called a butterfly one-way valve, between the two wings of the valve leaf is installed a spring to help the valve open and close.

+ Body of butterfly check valve wafer: Connects to the pipeline through a clamp connection. The valve body protects the components installed in the valve.

+ Disc of butterfly check valve wafer : Direct contact with the flow, composed of 2 halves of butterfly wings

+ Shaft of butterfly check valve wafer : Linked to the valve body and spring, helping to fix the spring.

+ Spring of butterfly check valve wafer : It is embedded in the valve shaft and linked to the valve.

+ When the refrigerant flow enters the valve, under the pressure of the flow, the force of the spring is applied, helping the spring to be compressed, pushing the two discs up from the closed position of the valve, and allowing the fluid to pass through the valve. When the flow stops, there will be two sources of pressure, the pressure of the reverse flow, and the elastic force of the spring to help the two valve discs return to the closed position to prevent the reverse flow.

• Materials of Check Valves

- Bronze and Brass Check Valve

- Stainless Steel Check Valve

- Cast Iron / Ductile Iron Check Valve

- Cast Steel Check Valve

- Plastic Check Valve

Advantages of Check Valve

- Valves operate fully automatically, with high service life

- Easy to install and replace, easy to check, maintain and clean the valve

- Works in a wide range of environments and environments

- Small design, does not take up much space on the system

- Diversity of types and types of connections and materials of manufacture

Chọn Mua Van 1 Chiều

- Materials body of check valve: SS 304, SS 316, SS 201, Cast iron, Ductile iron, Cast steel, Bronze, Brass, Plastic...

- Connection ends: Threaded ends BS - NPT, Flanged ends: JIS, BS,DIN,  ANSI

- Size: DN8, DN10, DN15, Dn20, DN25, DN32, DN40, DN50, DN65, DN80, DN100, DN125, DN150, DN200, DN250, DN300, DN400…

- Pressure range: 10kgf/cm2, 16kgf/cm2, 20kgf/cm2, 25kgf/cm2, 40kgf/cm2

- Temperature range: up to 450 độ C

- Types of check valves : Swing check valve, Lift check valve, Spring check valve...

- Brands: King gate, Joeun, Arita, Kitz, Samwoo, KSB

- Origin: China, Korea, Malaysia, Japan, Thailand, EU, Germany, USA...

Bronze & Brass Check Valves

- Brass check valve or brass check valve is a type of valve that works from brass. The check valve is also known as a non-return check valve and its role is to ensure that the flows do not have a reverse function. The disc rotates out of the valve seat to allow forward flow and when flow is stopped, the disc under the action of basic gravity returns to the seat to block the reverse flow. The return flow acts on special anti-backflow valves.

- Quality copper reduces natural corrosion, better than magic lines. The bearing pressure of the valve line is PN10, PN16

Key Features of ​​​​​Bronze & Brass Check Valves

- Compact design, beautiful appearance, precise operation, can be installed vertically and horizontally depending on the intended use.

- Diversity of models, operating forms and internal valve designs should be used with many different systems.

- Brass check valves have excellent properties for applications that are using air, water, oil or fuel.

- Less heat and corrosion resistant than stainless steel and is generally used for smaller applications with low pressure.

Technical Bronze & Brass Check Valve

- Size: DN15 - DN100

- Body: Bronze & Brass

- Disc: NBR rubber

- Style: Swing check valve, Spring check valve, Lift check valve

- Connection ends: Threaded ends, Flange ends

- Pressure range: PN10, PN16

- Temperature range: Max  120 độ C

- Media: Water, oil, steam. Air

- Brandst: Kitz, Arita, Yoshitake, Samwoo, King gate

- Origin: Việt Nam,Japan, Korea, China, Malaysia

Types of Bronze & Brass Check Valves

• Bronze & Brass Swing Check Valve

- Body of valve: made from brass, with high corrosion resistance

- Leaf of valve: made from frozen, stainless steel with durability, pressure resistance, high wear resistance.

- Cap of valve: made of copper, removable for cleaning and maintenance of the valve.

- Stem of valve: made from copper or stainless steel, where the valve leaf is attached and held.

- Principle of operation of the valve: when there is no valve flow in the closed state, the valve leaf presses close to the buffer, creating a closed system. The flow through creates pressure to push the valve leaf to tilt 45 degrees to allow the flow to pass. The flow pressure drops to the valve leaf slowly lowers and closes tightly to create a closed system, the valve returns to the closed state to prevent backflow.

• Bronze & Brass Spring Check Valve

-Body of valve: made from brass where the internal components are protected and under flow pressure.

- Stem of valve: made from copper, stainless steel with great durability to help perform the task well

- Sealing gasket of valve: with a gasket made of rubber, teflon has high sealing, avoiding leakage.

- Spring of valve: is attached between the valve shaft and the shield to create an elastic force to open and close the valve.

- Principle of operation of the valve: in the state of no flow, the valve is always closed, when there is flow through the pressure from the flow acting on the diaphragm and the spring pushes the diaphragm down to create the circulation of the flow. through. When the flow pressure drops, the spring force helps push the shield down to block the through hole and not allow the liquid to flow back.

• Bronze & Brass Lift Check Valve

- Body of valve: made of copper, designed in the form of a split globe valve, helping the valve reduce pressure

- Cover of valve: made of copper attached to the body by bolts, removable for cleaning and maintenance of internal components.

- Stem of valve: made from stainless steel, fitted with a shield and a push spring to open and close the valve

- Sealing gasket of valve: made of rubber, PTFE to create absolute tightness for the system

- The principle of operation of the valve: there is no gas flow through the valve in the closed state, the block seals the hole through. When the pressure gas flow passes through the shield and the valve shaft will be pushed up to create a system through the gas. Stop the gas supply. The stopper will push down to prevent air flow back into the system.

What is A Stainless Steel Check Valve ?

- Stainless steel check valve is a full body valve made from high-grade stainless steel material SS304 CF8 or SS316 CF8M or 201.Valve used for flow direction task allows passage in a certain direction.And prevent flow in the opposite direction.

- The valve has excellent performance, can withstand high temperature and high pressure. In addition, the valve's corrosion resistance is also very good, the mechanical strength of the valve is high. And it is widely used. for large industrial projects, factories, factories, pump systems in industrial zones, residential areas, high-rise buildings,...

Technical Stainless Steel Check Valve

- Size of Stainless steel check valve: DN15 - DN400.

- Material body of Stainless steel check valve: Inox 304, inox 201, inox 316.

Connection ends: Wafer, Flanged ends, Threaded ends

- Types of Stainless steel check valve : Swing check valve, Spring check valve, Lift check valve..

- Flanged ends standard: JIS 10K, BS PN16,DIN PN10, PN16, ANSI class150...

- Gasket: EPDM rubber, PTFE gastket

- Temperature range: 0 đến 250 độ C.

- Pressure range: PN10, PN16, PN25, PN40...

- Media: Steam, Water, Oil, Chemical...

- Origin: China, Korea, Malaysia, Japan, EU, USA...

Key Features of Stainless Steel Check Valve

- Valves are resistant to high temperature and high pressure.

- The mechanical strength of the valve is very good.

- High resistance to corrosion. Does not corrode over time of use.

- The valve operates fully automatically based on the system inlet pressure difference. Does not depend on any external force manipulation.

- Diverse sizes and connections to pipes, easy to choose and install.

- As you know, the check valve line has many types. And each type has a different structure and way of working. Let's find out in more detail about the valves currently offered on the market and how it works.

Types of Stainless Steel Check Valve

• Stainless Steel Swing Check Valve

- Body of stainless steel swing check valve : is designed with a bulb shape or a thin leaf shape. Connection can be flanged, wafer or threaded connection depending on the size.

- Disc of stainless steel swing check valve: is the part directly in contact with the flow. Flip-up operation flip-down blue hinge.

- Stem of Swing check valve:  Is a design detail similar to the hinge design. Combines firmly with the valve disc but still allows the valve disc to rotate around to create an open and closed state.

- Gasket:  Made from EPDM rubber or Teflon, PTFE,. Helps the valve when in the closed state to achieve the highest tightness and when the valve is closed to minimize the impact of the valve disc with the valve seat.

• Stainless Steel Butterfly Check Valve

- Body of stainless steel butterfly check valve :  Built-in monolithic to ensure the stability of valve operation in the best way.

- Disc of stainless steel butterfly check valve: is divided into 2 parts and combined to operate through the valve shaft.

- Spring of stainless steel butterfly check valve:  It is a part that helps to elasticize the 2 valve discs to the original closed position when stopping supplying input pressure to the valve.

- Stem of stainless steel butterfly check valve:  The part that connects the valve discs and springs together.

• Wafer Disc Stainless Steel Check Valve

- Body: thick monolithic casting design. The part that surrounds the rest of the valve parts.

- Disc: is the part that is in direct contact with the flow. Connected to the spring to create the opening and closing state for the valve.

- Spring: is an elastic part of the valve disc to create a closed state.

- Stem: is the part that connects to one end of the valve disc and the other end with a round hole positioned on the valve body to help fix the spring, valve disc and the direction of movement of the valve disc.

 

• Stainless Steel Lift Check Valve

The structure of the stainless steel lift disc one-way valve consists of 3 main parts:

- Body: designed with 2 threaded or flanged connections, the body is cast in spherical cast iron, heat-resistant steel, stainless steel, outside covered with Epoxy paint. Detailed parts include cap, bolt, nut.

- Disc: The one-way valve disc is designed from corrosion-resistant, high-temperature stainless steel, the valve disc is connected to a spring that works thanks to the pressure of the fluid.

- Spring : made of 304 stainless steel, the function of compression and feedback according to the pressure of the fluid helps the valve to open and close.

 

Advantages of Stainless Steel Check Valve

- Automatic operated based on the force of water flow, automatic quick opening and closing

- Valves have high durability, anti-rust, The replacement when necessary is simple

- Stainless steel check valves have many anddesigned with many sizes to suit different large and small pipelines

- Can be used in many different environments such as: Water, oil, compressed air, hot steam, chemicals, gases, other corrosive media...

What is A Forged Steel Check Valve ?

- The forged steel check valve can automatically open and close according to the flow of the medium. It is also known as one-way valve, backflow valve and back pressure valve, which is used to prevent backflow of refrigerant. The check valve is an automatic valve.

- Its main function is to prevent backflow of the refrigerant reverse rotation pump and drive motor, and discharge the refrigerant in the tank. Check valves can also be used to supply auxiliary systems where the pressure may rise above the system pressure.

- Non-return valves can be divided into swing (rotating hinged) check valves and lifting (moving along the shaft) check valves.

- Van 1 Chiều thép rèn A105 - A182 chịu nhiệt áp lực cao | Forged Steel check valves A105, A182 F304L, F316L Class 150, 300, 600, 800, 1500- 2000, 2500LB

Technical Forged Steel Check Valve

- Design standard: API 602, ASME B16.34, BS 5352

- The length of the structure: as per manufacturer’s standard

- Flange connecting end: ASME B16.5, GB/T 9113, HG/T 20592, EN 1092.1

- Butt welding connecting end: ASME B16.25, GB/T 12224

- Wall thickness: API 602, ASME B16.34, GB/T 12224

- Inspection and test: API 602, GB/T 13927

- Pressure and temperature rating: ASME B16.34, EN 12516, GB/T 12224

- Product scope: NPS 1/2 Inch - NPS 2 Inch (DN15 - DN50), Class 150 - 2500 LB (PN16 - PN420)

- Pressrue Rating – Class 150, 300, 600, 800, 900, 1500, 2500

- Main body material: ASTM A105, ASTM A182 LF2, ASTM A182 F11, ASTM A182 F22, ASTM A182 F51, ASTM A182 F91, ASTM A182 F304, ASTM A182 F316, ASTM A182 F304L, ASTM A182 F316L, etc.

Materials of Forged Steel Check Valve

Types of Forged Steel Check Valves

- Forged  Steel Wing Check Valve

- Forged  Steel Lift (Piston) Check Valve

- Forged  Steel Check Valve Y-Style

- Forged  Steel Ball Check Valve 

Appication of Cast Steel Check Valves

- Petroleum Refineries, Chemical Processing Plants, Steam, Cement, Power Generating Plants, and and other processing facilities throughout the world

What is A Plastic Check Valve ?

- Plastic Check Valve is a valve made of PVC, uPVC, cPVC. The valve only allows fluid to flow through the valve in one direction and prevents the flow of fluid through the valve in the opposite direction.

- Plastic one-way valve or plastic one-way valve, plastic one-way valve is a type of one-way valve made of PVC, uPVC, cPVC, PPR plastic materials, making the valve resistant to chemical environments. , waste water, oxidizing environment, and salt water, sea water, waste water...

Technical Plastic Check Valves

- Size:  21mm to 110mm

- Body of Plastic check valve: PVC, uPVC, cPVC

- Connection ends: CNS, JIS, BS, ANSI, DIN

- Pressure range: 0 - 150 psi

- Temperature range: 0 - 120°C

Key Features Plastic Check Valve

- Light weight valve, easy installation, easy to disassemble.

- Strong corrosion resistance, is hygienic, non-toxic material.

- Suitable for a variety of liquids: water, air, oil, corrosive chemical liquids.

- Diverse in materials, connection types, designs, so it is suitable for many different piping systems.

- Smooth surface design, low friction, helps to increase flow rate and prevent the growth of microorganisms, algae

Advantages - Defect of Plastic Check Valve

• Advantages of Plastic Check Valve

- PVC plastic has excellent acid resistance, alkali resistance, corrosion resistance, so it is not affected by moisture and soil pH. Has excellent anti-corrosion and chemical resistance properties.

- Good pressure resistance

The valve also ensures safety because of its insulating properties.

- Slim valve design for easy installation, maintenance and repair

- Cost is relatively cheap

- Able to insulate, can block 95-97% of heat radiation from outside.

- Able to insulate, avoid the risks caused by electricity. Reduce the possibility of fire, electric shock, ensuring safety for people and the system.

- Temperature resistant up to 180 degrees Celsius (for PTFE plastic valves)

• Defect of Plastic Check Valve

- The valve has the disadvantage that it will be decomposed at high temperatures or oxidized in direct sunlight due to poor thermal conductivity.

- Cannot be used in systems with high temperatures such as hot oil, saturated steam. Decomposes at high temperature.

- Not resistant to high pressure because it is plastic, so it is not suitable for systems with high pressure above 25 Bar.

Application of Plastic Check Valve

- The valve has a plastic leaf that prevents the automatic backflow of water.

- Suitable for backflow prevention in swimming pools, spas, solar panel installations, industrial applications, aquaculture, agricultural irrigation and water pump installations.

- Preventing flooding of wastewater due to the phenomenon of high tides in wastewater systems of households and factories.

- Swimming pool: the water in the pool is circulated in a closed cycle. The treated water is put into the dirty lake from the lake to the water treatment system and is supplied to the lake. One-way valves are installed at the swimming pools. water inlet and outlet locations.

- When the pump stops working, all the fluid in the pipeline will flow back out through the suction port and completely lose the pump's priming water for the next operation. So the one-way valve is responsible for not letting water. flows back out.

- In addition, for buildings with a tank system on the roof, when the pump stops working, it will cause a water hammer phenomenon that can damage the pump and equipment system on the pipeline. The one-way valve is also responsible for preventing this water hammer phenomenon.

Types of Plastic Check Valves

- Plastic Check Valve Swing Style

+ Plastic swing valve is a type of valve with an inner disc in the form of a flip door made from PVC, UPVC, CPVC, ... with many sizes from DN40-DN10). Suitable for multi-use aquatic environments and mainly used in small and medium-sized systems.
This type of valve works by the pressure of the fluid in the tube. When the fluid has not passed through the valve, it is closed by the gravity of the leaf plate, when the fluid through the valve creates pressure, pushing the valve blade upwards to help the fluid pass through the valve.

+ The feature is that it is possible to limit the phenomenon of water hammer causing damage to the rear equipment. The product has the highest price in plastic check valves.

- Plastic Check Valve Sping Style

+ Plastic spring check valve is a type of valve that opens and closes based on the elastic force of the spring made from PVC, UPVC,... Normally the flange of the valve will be closed to prevent the reverse flow of fluid, when it is stored. The material through the valve in the downstream creates a push on the flange, transmitting the spring force torque to create a space for the fluid to pass through the valve.

+ Size: dn15, dn20, dn25, dn32, dn40, dn50, dn65, dn80, dn100 for piping 21mm, phi 27mm, phi 34mm, phi 42mm, phi 48mm, phi 60mm, phi 90mm, phi 110mm.

- Plastic Check Valve Union Style

Cast Steel Check Valves

- Cast Steel Check Valve được sản xuất bằng thép Carbon đúc và kết nối với đường ống thường là mặt bích PN16- PN25- PN40, Ansi Class 150- 300- 600..

- Cast Steel Check Valves Flanged End are used mostly to prevent the medium from flowing back in the piping system. Cast Steel Check valves only allow the medium to flow in one direction, and when the medium flows in, the disc of Cast steel check valves swings off the seat to allow forward flow and when the flow stops, the disc swings back onto the seat to block reverse flow.

Technical Cast Steel Check Valve

- Size of Cast Steel Check Valve : DN40 - DN1200

- Body of valve : WCB Cast Steel

- Pressure range : PN10 - PN16 - PN25 - PN40 - PN63 - PN100 - PN160...

- Temperature range : 0 ~ 450 độ C

- Connection ends: Flanged ends (PN10, PN16, PN25, JIS 10K, JIS 16K, ANSI class 150, 300), Wafer style...

- Media : Petroleum, Chemical, Steam, Oil, Water...

- Origin : Taiwan, Korea, Japan, India, EU, USA, Malaysia...

Types of Cast Steel Check Valves

- Cast Steel Swing Check Valve Flanged Ends

- Cast Steel Lift Check Valve Flanged Ends

- Cast Steeln Dual-Plate Check Valve Wafer Style

Appication of Cast Steel Check Valves

- Petroleum Refineries, Chemical Processing Plants, Steam, Cement, Power Generating Plants, and and other processing facilities throughout the world.

Cast Iron / Ductile Iron Check Valves

- Cast Iron Check Valve - Ductile Iron Check valve được sản xuất với kết nối ren hoặc mặt bích JIS 10K, PN16, PN25. Van 1 chiều gang được dùng phổ biến ở hệ nước và hơi nóng, khí nén...

Technical Cast Iron / Ductile Iron Check Valve

- Size of Cast Iron / Ductile Iron Check Valve : DN50 - DN1200

- Body of valve : Cast Iron / Ductile Iron

- Pressure range : PN10 - PN16 - PN25

- Temperature range : 0 ~ 220 độ C

- Connection ends: Threaded ends (BS21, NPT), Flanged ends (PN10, PN16, PN25, JIS 10K, JIS 16K, ANSI class 150, 300), Wafer style...

- Media : nước, nước muối, khí hơi, chất ăn mòn,…

- Origin : Đài Loan, Trung Quốc,Hàn Quốc, Malaysia, Thổ Nhĩ Kỳ

Types of Cast Iron / Ductile Iron Check Valve

- Cast Iron/ Ductile Iron Swing Check Valve Flanged Ends

- Cast Iron/ Ductile Iron Lift Check Valve Flanged Ends

- Cast Iron / Ductile Iron Lift Check Valve Threaded Ends

- Cast Iron/ Ductile Iron Dual-Plate Check Valve Wafer Style