Special Flat Gate Valve

Your Professional Special Flat Gate Valve Suppliers in China

Zhejiang Advanced Technology Valve Co., Ltd. is a technology-based manufacturing enterprise, which integrates designing, manufacturing and marketing valves and owns one stop service. The company's leading products include flat gate valves with diversion holes, flat gate valves without diversion, expansion double gate flat gate valves, hard-sealed double gate flat gate valves, and special flat gate valves for alumina plants.

18 Month Warranty

We offers an 18-month warranty for each valve. Within these 18 months, if our products fail, leak, or even damage during use (excluding human factors), we will be responsible for replacing the products with quality problems and delivering them to your warehouse.

Advanced Equipment

The company has various precision machining and testing equipment, large-scale surface CNC grinders, sphere machining centers and other new technologies, as well as the first-class full-performance testing equipment in the country.

Wide Range of Applications

The valve products produced by the company are widely used in petroleum, natural gas, chemical industry, polysilicon, coal chemical industry, power station, metallurgy, papermaking, medicine, military industry and other industries.

Excellent Pre-sales Service

Our pre-sales service includes the communication and confirmation of a series of transaction terms before you place an order, including price, product drawings, trade terms, delivery date, etc. In addition, in the process of order production, we will let you know the status of the product in the form of pictures and videos to confirm the production process.

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Introduction of Special Flat Gate Valve

Special flat plate gate valve is designed on the basis of the line blind principle. A plane-parallel gate plate slides between two preloaded sealing rings and, in the open position, guarantees no obstruction in the pipeline with no resistance to the flow of the medium. The valve is used particularly for demanding sealing tasks and difficult media in the chemical, petrochemical and iron & steel industries.

Product Specification

Size	From 2″ to 48″
Body material	Carbon steel, stainless steel,
Nominal diameter	2"～36"
Pressure range	Class150～2500
End connection	RF, RTJ, BW
Working temperature	46℃～+200℃
Operation	Handwheel, gear box, electric, pneumatic actuator, electro-hydraulic actuator , etc.
Packing	To be packed in suitable wooden cases as per client's option or customized
Shipping & Delivery	20-25 days lead time; deliver by ship from Ningbo port or Shanghai port
Notes	Serial valve connecting flange and butt-welding terminal size can be designed at customers’ request. The material of the main parts and sealing surface of the valve can be designed and selected according to the actual working conditions or the special requirements of users.

Features of Special Flat Gate Valve

● Small flow resistance: Since the wedge slides on the two valve seat surfaces, the flat gate valve is also suitable for fluids with suspended particles.
● It has a double block and bleed function.
● Fireproof design: When the O-ring and PTFE are burned, under the action of fluid pressure, the wedge and the retainer, the retainer and the valve body form a metal seal, thereby isolating the fluid. In addition, the middle flange gasket and packing are made of graphite and metal materials to prevent external leakage.
● Self-releasing function: When the pressure in the middle cavity is high, the fixer will be pressed back under the action of the fluid in the middle cavity, so as to avoid accidents caused by excessive pressure in the middle cavity.

Operational Parts of the Flat Gate valve

Threaded
The valve has internal or external threads for inlet or outlet connection(s).

Compression Fitting
A sealed pipe connection without soldering or threading. As the nut on one fitting is tightened, it compresses a washer around the second pipe, forming a watertight closure.

Bolt Flange
The valve has a bolt flange(s) for inlet or outlet connection.

Clamp Flange
The valve has a clamp flange(s) for inlet or outlet connection.

Union
The valve has a union connection for inlet or outlet connection(s).

Tube Fitting
The valve has a connection for directly joining tubing at the inlet and/or outlet connections.

Butt Weld
The valve has a butt weld sized connection for inlet or outlet connection.

Socket Weld/Solder
The valve has a socket weld connection for inlet or outlet connection.

Metal Face Seal
The valve has a metal gasket sandwiched between two fitting parts. The gasket forms a face seal on each side of the fitting.

Bonnet
The bonnet of a gate valve contains the moving parts and is attached to the valve body. The bonnet can be removed from the body in order to allow for maintenance and replacing parts.

Trim
The trim of a gate valve contains the functioning pieces of the valve: the stem, the gate, the disc or wedge, and the seat rings.

Stem
The stem of a gate valve is either a rising stem or a nonrising stem. The stem is responsible for the proper positioning of the disk. Nonrising stems will almost always have a pointer-type indicator mounted onto the upper end of the stem to indicate valve position. This configuration protects the threads from carrying dirt into the packing because the stem threads are held within the boundary of the valve packing. Rising stems rise out of the flow path when the valve is opened. They can either have a stem that rises through the handwheel or have a stem that is threaded to the bonnet.

Seat
The seat of a gate valve is either integral with the valve body or in a seat ring type of configuration. The seat ring construction is either threaded on to the body or pressed into position and the seal welded to the valve body. Pressed and welded is recommended for higher temperature applications. Press-in or threaded-in seats permit variation in the seat material verses the material of the body of the valve.

Advantages of Special Flat Gate Valve

Just like a wedge gate valve, the main function of the flat gate valve is to control the pipe's switching, not to regulate medium flow in the pipe. The flat gate valve has low fluid resistance, easy to start and stop, short structure length, the free flow direction of pipe medium, and so on.
◆ Valve seat of flat gate valve uses 0-type sealing ring with pretension force and floating seat ring structure in order to have inlet and outlet two-way sealed. Besides, its on-off torque applies that of the ordinary valve, which can easily start and stop the valve.
◆ Valve seat of flat gate valve uses stainless steel inset or overlaid onto the sealing surface, with the double seal of metal and metal-to-metal, while sealing surface can remove dirt on the gate.
◆ Metal sealing valve sets injection structure outside of flat gate valve. The grease gets into the sealing surface through the injection device and valve seat, so that the valve has zero leakage.
◆ Valve gate with deflector hole always stays the same with the sealing surface, in order to protect sealing surface from direct corrosion of medium so that life service is prolonged.
◆ When the flat gate valve is fully open, with a smooth and flat channel, tiny flow resistance coefficient, and without pressure loss, the pipes can be cleaned by hairballs.
◆ The gate valve uses a packing structure with self-sealing capacity, doesn't need to adjust frequently, starts and stops easily, and has reliable sealing performance. The stuffing box is equipped with an auxiliary sealing injection structure, with reliable sealing performance and zero leakage, and solves the defect that general valve packing leaks easily.
◆ When stopping, high pressure at the end of the flat gate valve can be eliminated automatically for protective use.
◆ Flat gate valve has a fully enclosed structure, good protective performance, and can meet all-weather demands.
◆ Valve is equipped with indicating arm or observation window to indicate starting and closing of flat gate valve.

Maintenance and Precautions of Special Flat Gate Valve

01/

The strength and sealing tests have been carried out before the valve leaves the factory, and all connections should be kept in the initial state during use.

02/

The operating handwheel of this series of valves is marked with the sign of opening and closing rotation, and the upper part of the rising stem gate valve is equipped with an opening and closing height scale for adjustment instructions.

03/

When the valve is welded with the pipeline, the valve should be opened, and the flat gate valve should be properly protected with damp material to protect the neck, and minimize high temperature heat conduction to prevent damage to the sealing packing.

04/

It is strictly forbidden to use the extension bar when closing the valve. When the gate is closed to the top, the handwheel should be rotated 1/2 turn to make the gate in a floating state.

05/

During the use of the valve, a certain amount of grease should be injected into the bonnet grease joint regularly. If it leaks due to wearing parts, it should be replaced in time. During the maintenance process of the valve, the inner cavity should be cleaned. A grease should be added to each transmission part during assembly.

06/

During the storage period of the flat gate valve, the gate should be in the closed position, and it should be placed in a ventilated and dry place for the long-term storage, and it should be inspected and maintained regularly.

Troubleshooting Special Flat gate valves

Leakage Through the Valve-Pipe Connection

Worn-out seals/gasket. Replace the seals/gasket.
Loose connection of bolts and nuts. Tighten the bolts and nuts.
Excess fluid pressure. Ensure the fluid pressure is at the level.

Five-piece Flat Gate Valve without Diversion Hole

Recommended by the Gate Valve Manufacturer

Leakage through the bonnet-body connection.
Loose bolts and nuts. Tighten the bolts and nuts.
Worn-out seals/gaskets. Replace the gaskets/seals.

The Valve is Hard to Operate

There are clogged materials in the valve or on the valve stem. Disassemble the valve and remove such materials.
A bend on the valve stem. Replace the stem.
Extremely tight packing. Loosen the packing.

No Fluid Flows Through the Valve

The valve is blocked. Disassemble the valve and remove foreign materials from the valve.
Worn-out gate. Replace the gate.

Our Certificates

We guarantee that all our products have passed the quality control and stringent regulations imposed not only by our company but also by international organizations. Our certifications assure that our product line is top grade by industry standards.

Common Problem of Special Flat Gate Valve

Q: What is the main use of gate valves?

A: A gate valve is generally used to completely shut off fluid flow or, in the fully open position, provide full flow in a pipeline. Thus it is used either in the fully closed or fully open positions. A gate valve consists of a valve body, seat and disc, a spindle, gland, and a wheel for operating the valve.

Q: What is a gate valve best used for?

A: Gate valves are used to isolate specific areas of the water supply network during maintenance, repair works, new installations, as well as to reroute water flow throughout the pipeline.

Q: What is a slab gate valve used for?

A: This type of valve is very useful in transportation pipe lines for gas, crude oil and oil products. The Slab Gate Valve is through conduit and piggable. Slab Gate Valve has been designed to minimize pressure drop and catch foreign materials such as slurries into the disc cavity to keep clean the sealing surface areas.

Q: What is the primary application for gate valves?

A: Some common applications include: Oil and Gas: Gate valves are widely used in the oil and gas industry to control the flow of crude oil, natural gas, and other fluids in pipelines and refineries. Water Treatment: They are employed in water treatment plants to control water flow during purification processes.

Q: Why use a gate valve instead of a ball valve?

A: Flow Capacity: A gate valve can provide larger flow capacity than a ball valve as they are typically offered in larger diameters. Opening and closing speed: A ball valve is better suited for applications that require faster opening and closing speed or during emergencies due to its quarter turn on/off operation.

Q: What is the main disadvantage of the gate valve?

A: Assembly, start-up, and maintenance require large space. In the fully closed position, the slow movement of the slide causes high flow speed. Due to vibration and collision, abrasion and deformation occur in the seating surfaces and the surface gets damaged from friction.

Q: What is the alternative to a gate valve?

A: Compared to the gate valve, the butterfly valve-due to its specific construction-provides a much faster opening/closing action. The butterfly valve uses a fixed disc on a metal rod, which requires 90 degrees of rotation between the fully open and fully closed position.

Q: What is the difference between a gate valve and a slab gate valve?

A: Expanding gate valves include two units-a gate and segment-in contrast with slab gate valves, which have one unit. The gate and segment units collapse against each other for travel and separate when the valve is fully opened or fully closed to affect a mechanical seal.

Q: Do gate valves prevent backflow?

A: Rather than control water flow, gate valves simply allow or stop the flow of water altogether. All the while, these parts help prevent backflow, water hammer, and other harmful plumbing-related events.

Q: Does a gate valve reduce pressure?

A: Gate valves are equipped with a wedge-shaped metal gate that can be lowered to halt water flow and raised to allow flow to continue. When the gate is fully drawn up into the valve, it retracts entirely, allowing the water to flow through without any reduction in pressure.

Q: What industries use gate valves?

A: Gate valves are found in a variety of industries, such as underground water or sewage disposal applications. They are also commonly found in irrigation and distribution service lines. Gate valves are suited for high pressures and temperatures, and are also used for low-pressure steam, and non-corrosive gas or oil.

Q: What are the problems with gate valve?

A: The most common causes of gate valve failure are wear and the seat's and wedge's corrosion. The inner areas of a valve wear off over time, and corrosion can make the wedge stick in the open or closed position. When the handwheel is overused, the stem leading to the wedge breaks off and renders the valve useless.

Q: Should you throttle a gate valve?

A: Gate valves are not intended for throttling. They are designed such that media flowing at high velocity can vibrate and quickly erode or tear a partially-open valve disc off its seat. In a pinch, gate valves should only be used for throttling when the gate is 90% closed.

Q: Should gate valve be open or closed?

A: If water or another fluid flows through the valve in the direction of flow, this implies that the gate valve is in its open position. Conversely, if there is no discernable flow, then the faucet or gate valve is in a closed position.

Q: Should I use a gate valve or stop valve?

A: Gate valves are used to control the flow of liquids and gasses. They are often used in piping systems to regulate the flow of water or other fluids. On the other hand, stop valves are used to shut off the flow of liquids or gasses. They are often used in emergencies to shut off the flow of a substance quickly.

Q: How do you stop a gate valve from leaking?

A: Hence, the first step you should do to stop the leak is to tighten the packing nut. Replace the valve stem packing material or washer. When the gate valve's packing nut is tightened, it confines the packing material against the washer to prevent any water from passing through.

Q: What is the difference between a gate valve and a wedge gate valve?

A: Wedge valves have a conical or wedged-shaped disk, while gate valves have a flat disk. Wedge valves rely on a wedging action to seal, while gate valves rely on a linear motion. Wedge valves are well-suited for high-pressure applications, while gate valves are not. Wedge valves are more expensive than gate valves.

Q: What pressure should a gate valve be?

A: The main purpose of gate valve is to shut off the flow of fluids in a system. The valve is designed to be in either a fully opened or fully closed position. It is suitable to apply in low pressure application and the pressure rating can be up to 150 PSI working pressure.

Q: What is the technical name for gate valve?

A: Sluice valve or Gate Valve: These valves are used to regulate the flow of water in the pipe system. It is provided to control the flow of water in the distribution system at street corners and where the pipelines intersect.

Q: Do gate valves need maintenance?

A: Gate Valve's require periodic maintenance to inject a lubricant into the valve cavity. The purpose of the lubricant is to occupy the empty space in the valve cavity, displacing aggressive fluids and contaminants and acting as a barrier to prevent further ingress.

As one of the leading special flat gate valve enterprises in China, we warmly welcome you to buy bulk cheap special flat gate valve in stock here from our factory. All customized our products are with high quality and competitive price.

High Temperature Flat Gate Valve, Cryogenic Slab Gate Valve, Quick Closing Flat Gate Valve