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They are used on pipelines with a large diameter, more than 50 mm, where it is necessary to slowly shut off the flow to prevent water hammer.

At the valve, the valve moves perpendicularly, and at the moment of closing the sealing surfaces do not experience friction, which significantly reduces the occurrence of scoring.

Due to the fact that inside the valve body the flow direction changes twice, and the flow area is smaller than that of gate valves, the valve has increased hydraulic resistance, which is its main disadvantage.

The valve cannot be operated in different directions relative to the flow. Its working position is the direction of flow when, in a closed state, it presses on the plate from the side of the seat, and not from the side of the rod. In this position, the flow pressure when the valve opens even helps lift the plate from the seat. If the valve is installed incorrectly, the flow pressure in the closed position presses the plate, and when the valve is opened, a very significant force will have to be applied to move the rod, since it will be necessary to overcome the flow pressure. This can lead to its failure, since the shutter plate can be torn off the rod, which will require large labor costs for repair.

Cranes: main characteristics

A faucet differs from a valve and gate valve in that to start or stop the flow using a faucet, it is not necessary to rotate the spindle

They do not have a rod, and their valve is made in the shape of a ball, cone or cylinder with a hole for the passage of flow and rotates perpendicular to the flow. If the axis of the valve hole coincides with the axis of the pipeline, then the valve is open, since the flow passes through the hole. If the shutter is turned 90°, the valve will be closed. A faucet differs from a valve and gate valve in that to start or stop the flow using a faucet, it is not necessary to rotate the spindle. To do this, just turn the shutter 90°. This differs from a valve to a valve. It does not have a flywheel, so it is operated by a crank. The valve is in the open state if the handle is located along the pipeline, and if it is perpendicular, it is closed.

In cone valves, the valve is made as a truncated cone. It has a hole for the passage of flow in the form of a rectangle or circle. The valve body also has a conical surface. This was done so that the plug could fit tightly to the saddle.

For tightness, the seal is sealed with lubricant, which should fill all micro-gaps between the body and the shutter. At the same time, it reduces the force required to turn. The cork is pressed against the surface of the body.

There are two ways to press the shutter, and thereforeThere are gland and tension valves. In gland valves, between the upper end of the plug and the valve cover there is a gland packing. This is an elastic element that presses the valve to the body with constant force. Tension taps have a rod at the bottom of the plug that passes through the body hole. The shutter is pressed by a spring. Such taps are more reliable, since they do not have gland packing, the elastic properties of which are lost over time. Therefore, in such important industries as gas supply, tension cranes are used.

Cone valves have a low cost, they are not difficult to inspect, they have simple design and relatively low hydraulic resistance. This is their advantage

But such cranes also have disadvantages. It takes a lot of force to turn the plug. Over time, the microgaps between the shutter and the body surface become covered with deposits. In this case, turning the valve requires a lot of force, which can lead to breakage of the tap.

The production of taps requires a high-quality processed surface of the valve and body, so they are made of bronze and brass. In addition, these metals are less susceptible to corrosion, which extends its service life.

There is an opinion that valves are archaic and are already a thing of the past; ball valves and butterfly valves are coming on their heels. Ball valves are more compact, lighter, easier to install, control speed is literally in one movement and the ability to adjust the flow is an undoubted advantage of a ball valve over a gate valve. Let's look at some of the advantages of these locking devices.

Advantages of installing gate valves and ball valves.

When installing valves by welding, many people make mistakes that cannot be made when installing valves.
Some installers, having welded a ball valve and not allowing it to cool, and wanting to quickly check how it functions, tear off the fluoroplastic internal sealing elements of the valve valve in one movement.
Another common installation mistake is the vertical installation of ball valves by welding in the closed position of the valve. Welding splashes drip onto the mirror of the locking element - the ball and freeze on it, and then when the tap is turned, the frozen splashes tear apart the fluoroplastic seal. It is important to weld the tap only in open position shutter!
The valve is mounted on the pipeline longer, is heavier in weight and has a low gate control speed. In addition, the valve is only a shut-off valve and in no way regulating. But it does not have fluoroplastic parts, which indicates that the service life of the valves is longer than that of ball valves.
The service life of cranes is influenced by factors such as welded pipes. Some valves are made with pipes made of very high-quality steel; sometimes it even happens that the valve itself is designed for fortieth pressure, and the welded pipes are made of VGP for sixteenth pressure. Choose the faucet carefully, ask what steel the body and welded pipes are made of.

Benefits of operation.

Another factor in the advantage of gate valves over ball valves and gate valves is the likelihood of water hammer.
Water hammer in a pipeline is the mass of water in the pipeline plus pressure hitting the shut-off element shut-off valves when feeding the medium into the pipeline. Let’s say a plumber in the basement of a 16-story residential building turns the “wheel” - the flywheel of the water supply valve - one turn. The plumber understands perfectly well how open the through hole of the valve is and will wait until piping system will fill with water. While the valve “hisses” (bleeding air), he stands and smokes. If the plumber is not sober and wants to open the valve right away, he still won’t be able to do it, since you can rotate the flywheel for four minutes until it opens completely. Locking mechanism The valves are designed in such a way that the probability of water hammer is minimized or assumes a slight water hammer, which not all ball valves can withstand, since it is difficult to calculate how open the passage hole is.
A ball valve can be collapsible or non-collapsible, but the majority of manufactured valves are non-separable and are called maintenance-free. In case of jamming or any malfunction, the valve can be disassembled and repaired.

As a result, there will always be a confrontation between butterfly valves, ball valves and gate valves. Each of these shut-off valves is necessary for specific needs. It cannot be said that a valve is already a “dinosaur”, but a ball valve, no matter how beautiful and reliable it is, is progressive and perfect option for installation on a pipeline.

In our company "RosService" for installation on a pipeline you can always select steel valves 30s41nzh Ru16 DN 50-400, as well as Ball Valves for pressures from 0.6 to 4 MPa and under various diameters pipelines.

For specialists working in industrial enterprises, it is important to know the differences between a faucet and a gate valve.

general information

A valve is a drive fitting used for the manufacture of a pipeline, where the gate valve rotates around its own axis in a perpendicular direction. The element includes two components:

• Movable type cork;
• Static body.

A valve is a drive-type fitting where the structure moves along the flow and fits onto the seat. Designed for direct opening or closing, regulating the flow of any medium.

What are the main differences

It is customary to distinguish three types of fittings depending on their purpose:

1. Driven.
2. Regulating.
3. Constipated.

Some classifications add a safety group.

Considering the main differences between a valve and a ball valve, it is worth noting that in the first mount it is possible to adjust the fluid flow. A ball valve is not capable of performing this task. Based current rules, controlling and changing the flow of liquid using a ball valve is strictly prohibited by safety precautions. This is primarily due to the limited functions, since the regulator can only open or close the flow.

With the help of a valve, changes in the operating pressure are allowed due to the water pressure in the pipelines.

This is due to design differences that determine the functions and use of elements. Considering the main elements of the fixed valve body, the shutter mechanism in it “sits” on the seat. Its movement is carried out in the direction of the flow.

When operating a crane, turns are carried out around its own axis. If needed additional elements, plumbers use ball elements. When the ball begins to rotate, the diameter in the hole automatically changes.

The valve is equipped with a ground box. When the stems are screwed in/out, the valve moves up and down.

Comparing both designs, several conclusions can be drawn:

1. The valve is in the closed and open positions.
2. The valve is also capable of regulating the pressure.
3. To visually recognize whether it is a valve or a faucet, just pay attention to the handle. The faucet's structure is quite simple, unlike the valve (here it is presented in the form of a lamb).

When considering the main types of shut-off valves, it is recommended to consider another popular element - the valve.

There are several types of cranes, based on the body of rotation:

• Conical. Visually resembles the shape of a truncated cone. The hole can be seen in a rectangular or round shape. Most often used in gas supply. Popular due to its price.

• Cylindrical. Chief regulator of the heating system. Can perform vertical movement to regulate fluid flow.

• Ball. No plumber can do without it. The hole is made in a round shape through which the medium passes.

Why do you need a valve, the main advantages and nuances

A type of fitting where the adjustment part moves in a perpendicular position, moving in the direction of flow. Among representatives of this category, the valve is considered more relevant.

The tool is popular in use:

• Transport activities, where the diameter of products ranges from 15-2000mm;
• In creating water and gas supply;
• In the housing and communal services sector;
• Oil production.

The prevalence of the use of valves is due to the following aspects:

• Easy to operate;
• Small sizes;
• Allows operation in various conditions;
• There is a slight resistance in the hydraulics.

The last aspect is important when constructing highways. Constantly carried out in an environment characterized by high speed.

The mechanism is not without serious nuances. Experts in choosing necessary tools and materials, it is not recommended to use designs where the spindle is retractable. The shutter stroke is at least one diameter.

It is customary to distinguish two types of valves:

• Full bore.

• Narrowed.

The first one is the most common. In it, the full bore diameter is equated to the value of the pipeline on which the tool is installed. To reduce the amount of torque, valves are used to control the control of valves, including reducing the wear rate of other pipeline components.

There are several principles for controlling valves:

• Manually;
• By means of an electric drive system;
• By means of a pneumatic drive system;
• Through a hydraulic drive system.

Considering comparative characteristics between a tap and a valve, we can conclude that both elements have a number of similar features and differences.

comparison table

The tap and valve are very tight. This is why plumbers use them during plumbing repairs. However, the crane is characterized by less wear than that of gate valves. They can be used longer only if the following basic conditions are met:

• high-quality periodic maintenance,
• optimal lubrication.

Based on this table, we can conclude that the main differences between the two mechanisms can be traced in the following indicators:

1. How quickly parts wear out.
2. The amount of free space that will be needed outside the pipeline structure.
3. Where can it be used?

The crane does an excellent job as a traffic controller and can also act as a auxiliary element in regulating the supply of water or gas when high blood pressure. Therefore, when creating a pipeline, taps are often found at the end sections. Since the rotating element moves around its own axis, it does not require big place. But the control mechanisms will require space to place the valves.

A distinctive characteristic of mechanisms is the type of main mechanism. This is a system that moves in a perpendicular direction in a pipeline. The main element in the tap is a special valve. If it is placed parallel to the flow or at a small angle, the intensity of the movement of liquid or gas increases; if it is placed perpendicularly, the intensity decreases.

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Comparative characteristics of shut-off valves

General characteristics of different types of shut-off valves

Shut-off valves are used in the installation of gas pipelines and sewer systems. It can be seen on pipelines general purpose, industrial type, industrial pipelines with special conditions work, plumbing pipelines and many others. They are designed to block any water or gas flows.

For these purposes, a gate valve, tap, valve, valve, as well as other locking mechanisms are used. Household plumbing cannot do without such mechanisms, but few people understand the difference between a faucet and a valve. Without this it is simply impossible to connect household appliances, fix the leak, turn off the gas or change the mixer. Plumbing surrounds us all around us, and shut-off valves are an integral part of it.

In fact, it has significant differences, both design and operational, although any constructive solution This type of valve always works in two positions: closed and open.

But based on them functional characteristics and areas of application, one or another type of device is selected. For the right choice you should know how the principle of their operation may differ, and what function each of them performs.

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Operating principles of taps, valves and gate valves

Design solutions for shut-off valves include taps, valves and gate valves. How are they different from each other?

Gate valves are the most common and most popular locking devices. Their design implies that the locking element is in the closed and open position. The flow of the working medium is blocked due to the fact that the locking element moves perpendicular to its axis. Gate valves can be used exclusively as locking valves. They are parallel, wedge and gate.

A valve or valve is capable of blocking the flow of the working medium due to the fact that the device moves parallel to the axis of its movement. It, unlike valves, can be used not only as a shut-off device, but also as a regulating device due to the fact that its design will allow you not to completely block the flow of the medium, but partially.

A significant drawback is the valve’s inability to respond to changing speed and pressure in the system. Therefore, its scope of application is pipelines with a relatively constant flow and pressure of the working medium. In addition to regulating and locking devices, there are bypass, mixing, and distribution structures of these mechanisms.

A faucet is another type of shut-off valve. It can be used as a shut-off or a regulating device. It functions like this: the locking element, rotating around its axis, moves in a direction perpendicular to the movement of the medium flow. The locking element has the shape of a disk. Due to its rotation around its own axis, the liquid overlaps in a perpendicular direction.

Modern plumbing offers various design solutions for shut-off valves that have own characteristics. Of course, this entails distinctive advantages and disadvantages that manifest themselves in different conditions. Therefore, in order to choose the right shut-off valves, it is necessary to take into account the design features of the pipeline, as well as the conditions of use and requirements for a specific device. To do this, you need to understand the difference between, for example, a faucet and a valve, because the difference between them is not so obvious.

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Comparative characteristics of tap and valve

The main difference between a faucet and a valve is the adjustment of the pressure of the working medium. The valve can make such adjustments, but the faucet cannot. Moreover, taking into account the operating rules of taps, it is strictly prohibited to regulate the pressure using them. The tap has only two functions: open and close the flow of the medium. But the valve can easily regulate the pressure of liquid or gas.

This difference is due to design. The shut-off element in this device moves in the direction of flow and eventually sits on the seat. In cranes, it rotates around its axis. In addition, there are ball valves. In their design, the shut-off element is a ball that rotates perpendicular to the flow, as a result of which the diameter of the pipe changes. But the valves are equipped with a ground axle box. This design solution implies that by moving the axlebox rod, the valve, which is attached to the rod, is raised or lowered. Thus, the opening or closing of the hole located in the seat occurs.

Visually, it is easy to distinguish a valve from a faucet. If the shut-off valve has a simple handle, and the end of this handle is attached to the stem, then it is a faucet. If there is a thumb in place of the handle on the rod, it is a valve.

This article talks about wedge flanged valves, their characteristics, operating principles, and most importantly, the use of these products on different pipelines:

Wedge flanged valves are in demand in communications industrial production on water, oil, and gas pipelines. They are an indispensable part of any pipeline where it is necessary to block a section or the entire pipe. These shut-off valve elements are not complex in design; they have long terms operation (up to 50 years). For safe operation of the pipeline, they are installed at a certain distance from each other so that the pipe can be quickly shut off in the event of an accident or repair.

Flanged valves

Depending on the type of pipeline, appropriate shut-off valves are used. It is obvious that the range of valves used here is wide. Flange valves have found wide application in all areas of the national economy:

• In the heating system;
• In the transport industry when transporting petroleum products;
• In energy communication pipelines;
• In shipping pipelines.

Flange valve devices

Despite their simplicity, flanged wedge valves have high efficiency in a row of shut-off valves. Depending on the locking element, the type of wedge valve is determined. The flanged valve got its name because of its design: on its sides there are flanged disks that mate with the same disks on the pipe.

For flanges on the valve and on the pipe, the diameter and holes must strictly match, otherwise they cannot be connected. A gasket made of paronite, rubber or a rubber ring must be installed between the flanges, depending on the environment inside the pipe. This design of the wedge valve makes it quick-removable, which is important during repairs.

According to the design of the nut, wedge products are divided into 2 categories: with a retractable and fixed nut.

That is, in the first option, when opening or closing the valve, the nut moves progressively. In the second option, the nut remains in place and the screw moves out. In the second category, wedge valves occupy less space and they are used when moving petroleum products and other liquids that do not cause metal corrosion. Wedge products with a sliding nut are mainly used.

According to the closing method, devices are divided into valves:

• With manual control. Closing is done manually using a handle or valve;
• WITH automated control. With this type of closing, mainly electric motors with gearboxes are used, and they are turned on via a remote control by the operator. Hydraulic and pneumatic drives are used less frequently, due to the additional supply of pipes, instruments, etc.

Design features and application of valves

In addition, devices are divided according to their design. There are ball, gate and wedge valves. The latter are the most popular and in demand in the line of shut-off valves.

Flanged valves are manufactured in two versions: wedge and parallel devices.

Flanged Wedge Gate Valves

With wedge flange devices, the locking mechanism moves at an angle of 90 degrees to the flow. The sealing gaskets in them are installed at a certain angle to each other. Typically, such valves are used when moving water, gas, and oil products in pipes. The wedge itself can be solid, metal with rubber coating or made from two hard drives made of alloy steel. As a result of this assembly, it is possible to change the stuffing box without blocking the pipe. However, when using such products, sometimes the locking device jams due to temperature differences or damage to the gasket.

Clinket valve

The clinket valve inside has 2 disks rigidly connected to each other. Similar design reliable, it does not jam when moving, rubber gaskets wear minimally, and the valve is much easier to operate. Such valves are most common in pipelines on ships, due to the harmful effects of sea salt.

With parallel design, the surfaces are parallel to each other. They are also divided into valves: single-disc (gate); double disc valves.

Gate valves

Gate valves are used when the medium is directed in one direction. Due to their simple configuration, they cannot provide a hermetically sealed maximum overlap, but they are repairable. This makes it possible to use them in environments where mechanical particles are present, namely in sewer systems.

Wedge valves with ball locking mechanism

Devices with a ball mechanism are similar in design to household taps. The most popular models are DN50 due to their low cost. DN100 products are equipped with technological discs, which are pressed by springs and are used more in the gas industry.

Hose-type flanged devices

Hose-type valves are fundamentally different from their counterparts: they do not have seat seats. The liquid circulates through the hose, which, if necessary, is clamped with a shutter. Such device designs are used when the moving medium is aggressive and needs to be completely isolated from the valve body to avoid corrosion. Similar products are used in the chemical industry to move aggressive liquids during high temperature about 100 degrees and pressure up to 1.6 MPa.

Advantages and disadvantages of wedge valves

Among the main advantages, it is worth highlighting:

• Quick release connection. This makes it possible to quickly replace the device;
• The service life without repair reaches 50 years;
• Simplicity of design;
• Reliability of constipation;
• Slight effort when closing. The movement of the wedge-shaped disk occurs due to the rotation of the screw by the steering wheel.

The products also have flaws, the main one is the large overall height of the device. This especially applies to valves with a rising stem. After all, in them the screw stroke should be equal to the height of the valve itself. Wear is also considered a minus. rubber seals, which occurs as a result of prolonged opening of the product valve. And thirdly, when opening manually, it takes a lot of time to fully extend the locking device.