Slide valve for bulk materials by hand. Gate valves

All valves are designed to stop or allow the flow of fluid. Gate valves are one of the original valve designs that ideally perform this function.
The difference is that an element in the form of a barrier is used
metal wedge or plate. This design is capable of not only keeping out, but also cutting inclusions in liquids that flow inside the valve. Hence the areas of use of this equipment.

Areas of application for gate valves

Insensitivity to the presence of solid and fibrous inclusions in the working environment makes it possible to use this valve in many areas of human activity.
Namely:

• mining industry

• oil refining industry

• gas industry
• sewerage system
• pulp and paper production

• chemical and food industry

• ventilation systems
• construction. It is widely used in this area.

You will find it in almost all installations where material flows need to be contained or controlled. Thanks to the ability to create special geometric shapes and a variety of blades, it meets all the requirements of the construction sector, including the food sector.
This is not a complete list of applications; there are quite a few that can be listed. The scope of application can extend both on an industrial scale and in everyday life.

Why are gate valves needed:

• blocking the flow,
• separation function,
• regulate the power of the passing flow.

Types of gate valves

By control method:

• manual
• electric
• pneumonic
• hydraulic

By type of design: oblique and straight.

Based on the operating principle:

• unilateral

• reverse. Double direction gate valves differ from conventional types. They usually have two seats in a split housing.

Gate valves can be installed in any conditions, from horizontal to vertical positions. This will not affect their reliability.
Also distinguished:

• gate valves without sealing. The design of such equipment is quite simple. The valve is usually disc shaped.
• gate valves with seal. An additional rubber seal that provides a tight seal to the valve.

When installing gate valves great importance has the material from which they are made. The material is usually stainless, high carbon steel. The surfaces of the damper are painted with powder enamel.

The knife parts can be covered with abrasion-resistant plastic. This is typical for food and chemical industry. The gate itself is carefully polished to prevent the possibility of jamming. Nowadays, manufacturers are increasingly using non-traditional elastomers, and more innovative materials. This material allows you to increase the service life by two or more times.

What is this device?

As a rule, it consists of a body with elements with holes through which this medium passes. The shutter itself must be in the form of a disk or special for this equipment. Torque is transmitted to this shutter (see). It can be transmitted manually or automatically, depending on the type of control. This makes the damper move. Although manual mode is increasingly being replaced by automatic mode, in some cases it is indispensable. If there is a power failure, the system can still work productively. Therefore, today the possibility of combined modes is being considered.

There are also connecting pipes that are necessary for connecting to a pipeline or other device. Often used welding connection, but this is only with a pipeline. And in sewer systems, special pipes are used or the connection is made using.

Advantages of gate valves

• simplicity of design, small number of parts.
• ease of use.
• small overall dimensions.
• use for transportation of viscous working fluid.
• ease of maintenance.
• long service life.
• a wide range, and therefore a wide range of uses.

Hermetic design, silent operation, special rust removal system. Which is also of great importance.

Flaws

As with every system, there are drawbacks. Perfection, unfortunately, does not exist.
These include:

• long opening and closing times.
• difficulties in repair when sealing surfaces wear out during operation,
• high cost of repairs. This is usually caused by replacing a certain part or the entire structure, hence an expensive repair. But long term service fully compensates for this deficiency.
• impossibility of application for crystallizing drives in a given environment.

Conclusion

For many centuries, humanity has been using shutters. Of course, during this time they have changed and improved, but the principle of operation remains the same. They still represent a modern, simple and high-quality system that solves many problems, both in production and in everyday life.

When choosing modern gate valves, you can now choose a good quality-price ratio. Considering that the gate valve operates under conditions of increased loads, you should be more careful when choosing it. It is better to purchase products from trusted manufacturers. And often the higher cost pays off over a longer service life.

Thus, after conducting a study of this market, we can conclude that each option has its own disadvantages and advantages. Knowing them you can achieve excellent results. The main thing is to clearly define the task and approach the solution competently and individually. Today there are all possibilities for this. Experts will help you find the right solution in this matter.

The name “gate valve” is used for parallel valves, the locking element of which is made in the form of a plate. They are also referred to as a “knife gate valve,” although “GOST 24856-2014. Pipeline fittings. Terms and Definitions” does not recommend doing this.

Despite the fact that the gate valve is parallel, as they say, “by definition,” in the information space you can find the expression “wedge gate valve.”

The adjective “gate” is a derivative of the noun “gate”. The word “shiber” has a German “pedigree”, it comes from the verb schieben ─ to push, move, shove, etc.

If we talk about the general technical universal meaning of the term “gate” in Russian, then this is a moving plate that serves to block the flow of something. For example, a chimney damper─ damper in stove chimneys. A damper is a metal sheet that moves perpendicular to the axis of the air duct and serves to regulate the air flow by reducing the passage opening until it is completely blocked. Gate valves are found in boiler installations and water intake structures. A gate is a device for periodically blocking the lower part of a shaft installed in a waste collection chamber, which is used for loading solids. household waste into containers.

In pipeline fittings, a valve, along with a spool, disk, wedge, plunger, etc., is the movable part of the valve, which has the form of a plate. Thanks to its movement, it changes throughput fittings and the opening and closing of the flow section occurs.

IN English language A gate valve whose gate contains a gate is called a slidegatevalve or slabgatevalve. The gate itself is called differently ─ slab (English ─ plate, panel, piece); knife (English ─ knife); slidinggate (English ─ sliding gate); slidingplate (English: sliding plate).

Operating principle and design of gate valves

Moving, as is “supposed” for valves, perpendicular to the movement of the flow of the working medium, the gate opens and closes the passage hole. The force that the gate valve drive creates is transmitted to it through the spindle (rod).

The design of a gate valve includes the following main components and parts: body, knife (gate), stand, sealing element, stuffing box seal assembly.

The tightness of the gate valve in the closed state is ensured by pressing the knife (gate) to the seal under the influence of the pressure of the working medium. Gate valves are manufactured with one-sided and two-sided tightness.

Their design uses both retractable and non-retractable rods. The second option is especially popular when there is a shortage of space.

Frame

The gate valve body, which has a rectangular or cylindrical shape, is made as one-piece monolithic or prefabricated, welded, for example. A design feature of a gate valve may include a removable bottom cover and a through knife (gate).

For the manufacture of gate valve bodies, gray or high-strength cast iron with nodular graphite and various steels are used - carbon, low-alloy, stainless.

The material of a gate valve cannot but influence its resistance to aggressive environments. A cast iron gate valve resists the effects of gasoline somewhat worse than a steel one. diesel fuel, industrial and motor oil. A combined option is possible - the body is cast iron, and the parts in contact with aggressive environments are made of stainless steel. An epoxy coating can provide protection to the housing from corrosion.

For housings, not only ferrous metals are used, but also non-ferrous (aluminum alloys) and even non-metallic materials. The range of some manufacturers includes gate valves made of PVC (polyvinyl chloride).

Shiber (knife)

The valve gate may have the form of a plate made of thick rolled steel with parallel sealing surfaces. A hole is drilled in the slab, the diameter of which is equal to the diameter of the pipes located opposite, ─ this is the so-called. gate with a through hole. When the hole is located exactly opposite the nozzles, the gate valve is completely open, and when it “goes away,” the gate valve closes.

The gate may have a sharp edge, making it look like a guillotine or knife. A consequence of the similarity of the gate with a knife is the name “knife gate valve”, and with a guillotine ─ “guillotine-type gate valve”.

The presence of a beveled polished edge allows the gate, like a knife through butter, to penetrate into the working environment, ensuring rapid shutoff of the flow of even the most viscous, containing great amount mechanical inclusions, materials.

For knives (vanes) and spindles (rods), as a rule, stainless steel is used.

The knife is polished, the smooth surface ensures free sliding in places of contact with sealing materials and avoids various types of braking and jamming, which is especially important when the working environment contains many mechanical inclusions.

Seals

Gate valves can be made with a metal-to-metal seal (metal/metal) or with the use of more airtight soft seals made of synthetic materials.

Nitrile rubber resists the effects of petrochemical products well.

Rubber compounds based on SKN are distinguished by their performance in contact with oils and fuel, including in areas with cold climates.

High tightness even when exposed to aggressive liquids and high temperatures demonstrates Viton.

Gate valves used in the food and pharmaceutical industries use seals made of silicone.

The seal ensures a tight seal at the top of the gate valve. For its filling, cotton fiber (oiled and dry), synthetic fibers, graphite-containing materials, etc. are used.

Methods for controlling gate valves

Gate valves can be equipped with various types control: manual or hydraulic, pneumatic, electric drive.

For relatively small nominal diameters, a manual drive is often used - a manual gate valve. This can be a handwheel (steering wheel) with a retractable or non-retractable rod, a lever or a square attachment for a T-shaped wrench. A flywheel with a chain is used when the valve is located in a hard-to-reach place. The lever is used for small nominal diameters (DN up to 200-300). Reducer ─ with sufficiently large values ​​of DN and PN.

If it is necessary to control gate valves large sizes, resort to the help of a mechanized (automatic) drive.

They use a single- or double-acting pneumatic drive, including a manual override. The extreme positions of the knife are set using adjusting bolts.

Electrically driven gate valves for fixing the extreme positions of the knife are equipped with limit switches.

Pipeline connection

For gate valves, the following connection types are used: flanged (flanged gate valve), wafer (wafer gate valve), butt weld.

With a wafer connection, a gate valve is installed between flanges welded to the pipeline. Bolts or studs are used to secure the valve. The tightness of the connection is ensured using wafer gaskets.

Advantages of gate valves

Gate valves, which make up a significant part of the range of many manufacturers of pipeline fittings, have a number of advantages, the most significant of which are given below in the form of short abstracts.

• Gate valves have a short overall length, for example, compared to cranes.
• The design of a gate valve is relatively simple, which, on the one hand, determines the ease of its installation (for example, the possibility of replacement without cutting into the pipeline) and ease of operation, and on the other hand, reliability.
• Reliability indicators largely depend on the parameters of the working environment ─ its aggressiveness, temperature, concentration of mechanical impurities.
• Gate valves are unpretentious and not capricious equipment; their maintenance and repair do not require very highly qualified personnel.
• Gate valves from the best manufacturers who use high-quality components and modern materials, have such important properties as durability, resistance to wear and exposure to aggressive environments.
• The service life of gate valves can be measured at three or more decades, determined by the service life of the body. For other components it is smaller, but also very impressive. For example, for rubber products - at least 5 years. The same is the average service life between major repairs of a gate valve.
• The absence of stagnant zones and the ability to self-clean allow you not to think about slag and dirt.
• An important parameter is the minimum hydraulic resistance of the medium. For example, gate valves manufactured by ARMATEK have a coefficient of hydraulic resistance of no more than 0.3 when the blade is fully open.
• Gate valves have unique technical capabilities, including fast operation and high tightness. Including the tightness of the high class And according to GOST R 54808-2011. Pipeline fittings. Standards for tightness of valves."

Technical parameters and a wide range of functionality ─ a range of sizes, pressures and temperatures that meet all needs ─ make gate valves truly universal pipeline fittings, in demand in a wide variety of technology fields.

Application of gate valves

The design features of gate valves make their presence especially appropriate in pipeline systems that ensure the movement of complex working media. For example, media characterized by a high content of mechanical inclusions, high viscosity, pulp-like (pulp is formed by mixing solid particles and liquid) and even granular.

Scroll technological processes, for which the ability of gate valves to handle materials that are absolutely unacceptable for many other types of pipeline fittings is of fundamental importance, is very wide.

• Mining industry

The most important segment of the mining industry is mineral processing. As reserves of ore and nonmetallic raw materials are depleted and the share of useful components in their composition decreases, the importance of enrichment only increases. Gate valves are widely used in process plants processing plants to ensure the efficiency of the processes of transportation, washing, chemical treatment, dosing of raw materials, classification and preparation of pulps, filtrate removal and many other operations.

• Oil and gas industry

Along with the mining industry, Stanovoy Ridge Russian economy is the oil and gas industry.

Gate valves are part of the Christmas tree equipment used in hydrocarbon production. Gate valves are also installed on main oil pipelines, where they serve as a guarantee for immediately shutting off the flow of crude oil. There is even a special regulatory document ─ “GOST 55020-2012. Pipeline fittings. Gate valves for main oil pipelines. General technical conditions".

• Chemical industry

Gate valves are mounted on production and technological lines that ensure the release wide range chemical products - ammonia, aromatic hydrocarbons, liquid glass, mastics, mineral fertilizers, paraffins, solvents, acids, etc.

• Production of building materials

Gate valves are used in installations for washing sand and producing bulk and granular materials - gypsum, dolomite, lime, chalk.

Gate valves are widely used in cement production equipment.

• Electric power and utilities

Gate valves are used in the electric power industry, including such a critical segment of this industry as nuclear power. In particular, gate valves produced by ARMATEK were supplied to the Rostov NPP.

Gate valves are installed by city water utilities on water supply and sewerage networks. They are extremely effective when completing equipment that ensures the transportation of industrial and municipal wastewater to processing sites.

Gate valves are successfully used in a number of industries not listed above - food, pulp and paper, woodworking, metallurgical, textile. And also in agriculture, on wastewater treatment plants and in many other areas of technology.

Designation of gate valves

"GOST 24856-2014. Pipeline fittings. Terms and Definitions” does not recommend using phrases with the adjective “conventional” instead of the term “nominal diameter”, such as ─ nominal diameter, nominal bore, nominal diameter. Nevertheless, even today everyone understands perfectly well what the combination of the letters “Du” means in the words gate valve Du100 (and further Du150, Du200, Du400, Du500...). Sometimes “Du” or in accordance with currently valid regulatory documents─ DN, omitted, saying: gate valve (gate valve) 200 250, 300, 400, 1000.

Appendix B (recommended) “Recommendations for forming the name of fittings in documentation” to the above-mentioned GOST recommends forming the name of fittings according to the following scheme: “type of fittings ↔ type of fittings ↔ design type ↔ DN ↔ PN”.

Many manufacturers of pipeline fittings use their own naming principle, trying to make it as informative as possible. For example, for gate valves the ARMATEK company uses the following algorithm:

“type of product ↔ connection to the pipeline ↔ type of actuator ↔ nominal pressure of the working medium ↔ nominal diameter ↔ climatic version ↔ seal design ↔ body material ↔ material and design of the spindle ↔ knife material ↔ seal material.”

Whatever you call it gate valve, one thing is obvious ─this design option of valves has, without exaggeration, great unique opportunities, successfully demonstrating them in a variety of industries.

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• type Ш. Does not have a seal. It is distinguished by a symmetrical locking element, located arbitrarily in relation to the direction of flow of the working medium.
• type ShN. Has a rubber seal. Equipped with a P-shaped rubber sealing element, which allows for increased tightness compared to the first type. The operating position of a gate of this type determines the direction of flow of the working medium - the shield seal is pressed against the gate body by the flow.

Design and principle of operation of a slide valve

Scheme of the device of a circular gate valve: 1-body, 2-knife, 3-herring, 4-sealing rubber, 5-cover, 6-rod, 7-nut, 8-yoke, 9-bushing, 10-ring-retainer, 11-steering wheel, 12-cap, 13-protection, 14-gasket.

An electrically driven gate valve consists of a body with two saddles located inside - fixed elements with holes that are designed to allow the medium to pass through them. Inside the body, between the saddles, there is a shutter, which is made in the shape of a disk. Using a threaded nut-spindle pair, torque is transmitted to it. This device can be either electrically driven or controlled by a gearbox, manual or pneumatic drive. The spindle, driven by a drive or a handle, rotates and causes the disk to move. The disk rises upward when torque is transmitted from the spindle, thereby opening a passage for the working medium. Or it goes down, which leads to blocking the passage.

Two connecting pipes extend from the body of the device, thanks to them it can be connected to the pipeline. The connection method is usually flanged, rarely - coupling for small nominal bore diameters. A locking element sharpened along the entire edge is called a knife gate. Such sharpness makes it possible to use the device to block the flow of abrasive and granular media. The knife bolt is made from high strength steel. During operation, it is polished to prevent jamming.

The scope of use of gate valves is very large. They are used in sewer systems, as well as at treatment facilities in almost all areas of industry. As a rule, a knife gate valve is used as a shut-off and control valve for pipeline systems through which hazardous media are transported. It is distinguished by a fairly simple design and optimal construction length, which are ideally combined with each other. The design provides for the presence of a special wedge or knife, which guarantees reliable and effective blocking of the flow of the working medium.

It is recommended to install a gate valve with an electric drive on pipelines with large diameters., which are characterized by moderate indicators regarding hydraulic resistance. In the case of transporting aggressive substances through pipes, such a device cannot be avoided.

The following types of gate valves can be distinguished:

- ShN type.

The first type does not have a sealing element, and the locking part is made in a symmetrical shape. The second type has a seal, which in most cases is made of rubber. The locking part has a P shape, which in turn makes it possible to achieve solid strength indicators.

The manual gate valve has a simple design and a disc-shaped gate valve. This is a reliable and functional device with clear and simple controls. They are further divided into two-sided or one-sided, as well as wafer and hopper. Maximum ease of operation is achieved thanks to the presence of a steering wheel, lever and electric drive. Manual control is characterized by several options:

• control using a steering wheel with a fixed rod;
• control is carried out thanks to a chain, lever or cardan transmission.

In the manufacture of gate valves for bulk materials, the following is used:

• high-strength cast iron;
• carbon steel;
• heat-resistant alloys;
• alloy steel;
• titanium.

The bodies of such valves have high strength, which allows them to be used for a long period of time. They operate absolutely silently, have good tightness and are easy to install. They are also equipped with an effective cleaning system that prevents the accumulation of various dirt.

Buy knife gate valves for bulk materials

By contacting our specialized company, you can quickly and profitably buy a gate valve in any quantity. If you have any questions, our specialists will give comprehensive answers and tell you about the main features of a particular product. Valves for various industries have the necessary permits from Rostechnadzor of the Russian Federation, as well as quality certificates. When choosing a manufacturing material, the characteristics of the working environment are taken into account, temperature regime, as well as pressure. The customer can choose the version of the product himself.

Prices for gate valves with electric drive or manual

The price of a slide gate valve, which will be pleasant for all our customers, is an indispensable element for the normal functioning of pipelines. Our website presents a huge range of pipe fittings, which are highly reliable and easy to use. A convenient presentation of gate valve models on the website will allow you to study their main characteristics in detail and buy the device you like.