What is Gate Valve ?

- Here is a Gate valve (or stop valve) is an opening and closing valve by lifting and lowering a gate, it has name Vietnamese (Van cổng)

Structure of Stainless Steel Globe Valves

- Body of a Gate valve: Bronze, Brass, cast iron, ductile iron, cast steel, stainless steel (SUS 201, SUS 304, SUS 316)

- Stem of a Gate valve: The stem, which connects the handwheel and disk with each other, is responsible for the proper positioning of the disk (Rising Stem and Non Rising Stem)

- Bonnet of a Gate valve: The bonnet is located on top of the body. This is where the stem passes through, thereby guiding it, as it connects to the disc. There are three kinds of gate valve bonnets. 

- Cover of a Gate valve: là phần trên của van được liên kết với thân van bằng bulong, được thiết kế với mục đích để tháo lắp bảo dưỡng và lắp ráp các linh kiện trong van.

Seats of a Gate valve: Seats for Gate valves are either provided integral with the valve body or in a seat ring type of construction

- Disks of a Gate valve: Gate valves are available with different disks or wedges. Ranging of the Gate valves is usually made by the type of wedge used.

- Handwheel of a Gate valve: Material (cast iron, ductile iron, cast steel, stainless steel (SUS 201, SUS 304, SUS 316)). Actuator: Often, you’d find gate valves with handwheels. When operating torque is high, the handwheel is replaced by gears or some kind of actuator. These are fixed with a nut.  This signals the opening or closing of the valve. Often you’d find markings that indicate which direction to open or close. 

How Does a Gate Valve Work ?

- To close the valve, you should rotate the handwheel clockwise. This will move the gate and the stem downwards towards the seat at the lower bottom of the valve. This is the complete closure of the gate valve. The media is blocked in the upstream inlet so no leakage happens. No excessive pressure should be applied when closing the valve to prevent the stem from breaking.

- To open the valve, you should rotate the valve in counter-clockwise order. Do this without applying too much pressure because it can damage the disc and stem, and leak. If there is pressure, stop turning.

How Does a Gate Valve Work

Types of Gate Valves

• Structure of a Gate Valve

- Rising Stem Gate Valve

+ Rising stem gate valves have the threads external to the valve body. The gate valve stem is moving up when the valve is opening. Rising stem valves are usually made from cast or forged steel while non rising stem valves are more typically brass, bronze or cast iron. 

+ Rising stem gate valves can be used in high pressure rating up to Class 2500 or up to 420 bar, while non rising stem gate valves are normally used for middle pressure rating.

- Non Rising Stem Gate Valve

+ The Non rising stem gate valves take small space to opearate and rising stem gate valves require more space. The construction of the non-rising is designe in such way that the stem of the gate valve is fully open when the handle is rotated as far as possible to the left and fully closed when the handle is rotated as far as possible to the right.

+ In both cases the handle is flush with the pipe because the mechanism inside the pipe opens and closes the valve without raising the stem.

+ Another advantage to the non-rising stem gate valve is that it is easier to padlock. Non rising stem gate valves are usually only used on clean liquids and gases.

• Gate Valve Material Selection Guide

Material of gate valves: Bronze, Brass, cast iron, cast carbon steel, ductile iron, gunmetal, stainless steel, alloy steels, and forged steels...

- Cast iron / Ductile iron Gate Valve :

- Bronze / Brass Gate Valves :

- Carbon Cast Steel Gate Valves:

- Stainless Steel Gate Valves:

Advantages and Disadvantages of Gate Valve 

• Advantages:

- The system does not lose performance when fully opened.

- The valve can be used in environments containing solid particles and high velocity, and can also be used as a vent valve and a low vacuum system valve.

- It has a shorter, faster opening and closing process, using less energy in the opening and closing work.

- The valve body is simple and easy to install, operate, and maintain.

- The valve opens and closes from the source, so it does not cause the application of the phenomenon that causes pipe robbery.

- The valve operates in both directions, allowing fluid flow to enter both ends

• Disadvantages:

- The valve is not used in regulating applications.

- The sealing surface is easily damaged when the disc is opened/closed and the valve seat has friction.

- The opening and closing time of the valve is very long compared to other types of valves.

- Complex configuration, high repair cost and also difficult.

- The outside size is quite large, requiring large space for installation and operation.

- When partially opened, the fluid pressure acting on the valve causes noise and vibration

What is a Gate Valve Used for ?

- Food Services, Pharmaceutical Services,  Feedwater Applications,  Hydrocarbon Applications,  Steam Applications, Slurry Application,  Powder Product Application, Petrochemical and Refinery...

Gate Valves Selection Guide

Forged Steel Gate Valves

- Van Cửa Thép Rèn - van cổng thép rèn ASTM A105- A182 (F304, F316, F304L, F316L) Forged steel- stainless steel gate valve Class ANSI 150, 300, 600, 900, 1500, 2500

Description - Forged Steel Gate Valves

- Forged Steel Gate Valves are Bolted Bonnet, outside screw and yoke type, Rising Spindle construction Body and bonnet made from high quality forgings.

- Relia Forged Steel Gate Valves in size 1/2 (DN15) to 2 (DN50) to suit various critical, non-critical applications and pressure rating up to Class 2500.

- Full or standard port. Bolted or welded bonnet joint. Integral backseat.

Types of Forged Steel Gate Valves

- Forged Steel Gate Valve Flanged Ends

- Forged Steel Gate Valve Socket weld Ends (SW Ends)

- Forged Steel Gate Valve Threaded Ends

- Forged Steel Gate Valve Butt weld (BW)

- Forged Steel Gate Valve Cryogenic

- Forged Steel Gate Valve welded bonnet

Technical Forged Steel Gate Valves

- Standard: API 602 / ASME B16.34 / BS 5352

- Size: ¼’’ - 2’’

- Pressure Range:

+ Class 150, class 300, class 600, class 900, class 1500, class 2500

+ JIS 10K, JIS 20K, JIS 40K, JIS 60K, 80K

+ PN10, PN16, PN25, PN40, PN64, PN100, PN160, PN250

- Connection Ends:

+ Flange ends

+ SW (Socket weld ends)

+ BW (Butt weld ends)

+ Threaded ends

- Body Material:

+ Carbon steel: A105, LF2

+ Inox: F304, 304L, 304H, F316, 316L, 316H, 317, 317L, F321, 321H…

+ Thép hợp kim: F5, F9, F91, F11, F22, Alloy 20, Monel 400, Monel K-500, Incoloy 800…

- Checked:  API 598

• A182 F304 Forged Steel Gate Valve Flanged Ends

- Class 800

- Type: Forged Steel Gate Valves

- Disc Type: Solid Wedge Disc

- Structure: Bolted Cover

- Bort: Reduced Bore

- Ends: Welded Flanged RF

- Body: ASTM A182 F304

- Trim: ASTM A182 F304

- Seat: Stellite 6 Overlay

• A182 F22 Forged Steel Gate Valve SW Ends

- Class 1500

- Design: API 602

- Body: ASTM A182 F22

- Trim: API 600 Trim 10

- End Connection: SW (Socket Welding)

• Forged Steel Gate Valve Class 800

- Forged Steel Gate Valve Class 800

- bolted bonnet, outside screw and yoke type.

- Forged Steel Gate Valve Class 800 rising spindle construction body and bonnet made from high quality forgings.

- Forged Steel Gate Valve Class 800 are Bolted Bonnet, outside screw and yoke type, Rising Spindle construction. Body and bonnet made from high quality forgings.

- Relia Forged Steel Gate Valves in size 1/2 (DN15) to 2 (DN50) to suit various critical, non-critical applications and pressure rating up to Class 2500.

- This heavy duty class 800 forged  steel Gate Valve is suitable for the most demanding of process applications.

- When open the media will flow with a minimal amount of turbulence and pressure drop through the valve and industries where the isolation of viscous fluids and liquid are required.

- The forged steel gate valve is designed to API602 and has an outside screw and yolk with rising stem. The handwheel operates the gate valve for both isolation applications only.

- Why use forged steel gate valve: these valves provide a positive tight shut off in the horizontal or vertical position for process fluids in pipelines.

- They also offer a small amount of control and are used to throttle steam, gas or liquids. Easy to operate and the preferred choice over ball valves by engineers to isolate trapping stations.

• Pressure Seal Forged Steel Gate Valve

- Gate Valve, Pressure Seal, Forged Steel, Butt Weld Ends, ASTM A105N.

- Structure: Pressure Seal Bonnet

- End Connection: BW (Butt Welding) or Flange

- Body Material: ASTM A105N, F11 etc.

- Trim Material: API 600 Trim No 5, 8 etc.

- Standards Design : ASME B16.34

- Standards End to End : ASME B16.10

- Standards Test : API 598

- Standards BW End : ASME B16.25

- Standards Test : API 598

• API 602 Forged Steel Valve

- Gate Valve, Forged Steel, API 602, Full port and conventional port optional,Bolted bonnet; welded bonnet; or pressure seal bonnet

- Full port and conventional port optional

- Outside screw and yoke (OS & Y)

- Solid wedge (disc)

- Renewable seat ring

- Non-rising handwheel

- Bolted bonnet; welded bonnet; or pressure seal bonnet

- Integral backseat

- Two piece self aligning packing gland

- Standard Design : API 602/ASME B16.34

- Standard Face to face dimension : ASME B 16.10

- Standard Socket welding end : ASME B 16.11

- Standard Threaded end : ASME B B 1.20.1

- Standard Butt welding end : ASME B 16.25

- Standard Flange end : ASME B 16.5

- Standard Inspection : API 598

• Range of API 602 Forged Steel Gate Valves

- Body Material : Carbon Steel/Stainless Steel/Alloy Steel (Forged Steel, such as A105N, LF2, F304, F316, F11, F51, F91, F347 etc.)

- Trim Material : API 600 Trim number 1 to 17

- End Connection : Flange/SW/Thread/BW

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

- Size : 1/2″ - 2″

Materials of Forged Steel Gate Valves

Remarks:

- Select different materials for different working temperature and media.

- Trim materials and recommended service coverage referred to Appendix

Connecting Form Between Valve Body and Bonnet

- The connecting forms between valve body and bonnet of our forged steel valve include three kinds: bolt connection bonnet, welded bonnet and pressure seal bonnet (Shown as the following figure). The choices of structure form are shown as in the table. The specific forms chosen by customers should be given for the order.

Connection Ends of Forged Steel Gate Valves

Connection Ends Of Forged Gate Valve