Types of stopcocks. Shut-off valves, material for its manufacture and types of equipment
Shut-off valves
No pipeline can be imagined without shutoff valves. Shut-off valves are dampers, valves, Ball Valves and almost everything else. This is the big tumbler on the big oil pipeline, and the small water faucet in your bathroom. Shut-off valves are represented by any kind of valves or other systems that are designed to regulate or prevent the upcoming movement of the upcoming contents of the pipes. Imagine for a second what would happen if all the pipelines in the world were deprived of these tools of control: endlessly flowing water, oil from taps and pipes that would pour into rivers and lakes, destroying the ecosphere.
Shut-off valves are installed and used on pipeline lines to control the flow of working media by configuring the flow area. They are connected to the pipeline by means of welded, flanged, coupling and fitting connections. Specifically, shut-off and control valves create the necessary pressure, with the help of which water or gas enters our houses or apartments.
The main properties of valves
Shut-off valves have two main properties: conditional passage and conditional pressure. The conditional passage is the nominal internal diameter of the pipeline (mm) attached to the valve. Nominal pressure is the highest excess pressure at a working medium temperature of 200°C. With all this pressure, a given service life of connections having certain dimensions is ensured. The difference between the working pressure and the conditional one is that it ensures this mode of operation of the shut-off valves under large excess loads. Shut-off valves are also responsible for the safety of technological processes, therefore it is very important that they comply with all technical requirements was reliable and high quality.
Types of shut-off and control valves
By the type of technological process and various parameters of the working medium, such as pressure, chemical composition, temperature, shut-off and control valves can be divided into different types:
1. Control valves are valves that regulate the characteristics of the working medium in the pipeline. The regulating type of fittings includes water level regulators, various control valves, pressure regulators.
2. Shut-off valves are valves that are designed to completely shut off the pipeline, which is necessary in case of disasters or repair work. Shut-off valves include ball valves and gate valves.
3. Protective fittings - used to protect pipelines and equipment in automatic mode from unexpected or contrary to the envisaged configurations of process characteristics or configurations of the movement of the working medium. Protective fittings include various shut-off and reverse valves.
4. Phase dividing fittings - designed to separate working media in automatic mode. Phase separation fittings include various air vents, steam traps and oil separators.
5. Safety valves - designed to protect the pipeline and equipment in automatic mode from overpressure. Safety fittings include valves, overflow valves and safety impulse devices.
Reliable valve suppliers
The durability of the entire pipeline system depends on the properties and reliability of valves. Shut-off valves must be airtight and meet all technical requirements. Our company "AS Group Ukraine" is a distributor of recognizable manufacturers of valves, ball valves and other products for heating, water supply and plumbing systems. Contact the specialists of our company, and they will select high-quality and reliable equipment from the manufacturer.
As a distributor company, we represent such well-known and necessary brands as: TM "Blue ocean" (England), TM "Valtec" (Italy), TM "Santehplast" (Ukraine), TM "AS Gruppe", TM "EVO", TM Eco-Flex (Turkey), TM Nova Voda, TM Atlas Filtri, TM Siamp, TM FTN, TM Haiba, TM Pexal, TM Omni Aqwa Pompy.
Steel, brass, bronze and ductile iron are the main materials for the manufacture of any kind of valves. These types include a variety of taps, valves, dampers and gate valves, each of which is used only when all the technical conditions of a single pipe are taken into account and met. For example, for systems for pumping aggressive substances and for waterways, radically different types of equipment are used. Let's take a closer look at all types.
In fact, taps can be installed on any water supply. They are fastened with a coupling or flange connection (sometimes the branch pipes of the valves are welded to the pipeline). Distinguish between plug and ball valves, and also, descending from the working environment, they are also divided into:
- flanged ball valves made of steel or cast iron. Operation of steel cranes is possible at temperatures up to seventy degrees, and cast iron up to one hundred degrees.
- cork couplings are made of cast iron and are most often used for gas pipelines. Operation is possible at a temperature of the working environment not higher than fifty degrees. Mounting is provided in any position.
- gland sleeve valves (plug valves) are made of cast iron. Most often used on water and oil lines at a temperature regime of the working environment not higher than one hundred degrees. The composition includes an oil seal stuffed with foam or rubber. Mounting is possible in any position.
Shut-off dampers as one of the types of shut-off valves
This is a pipeline valve, the locking element of which is a disk rotating around its axis. It is the dampers that are recommended to be used on a pipeline with a large diameter and high pressure. As a rule, they are made of cast iron, and the rotary disk is made of steel. This type of fitting is cut into the pipeline by welding or flange connection.
The dampers can be operated electrically, hydraulically or manually. They are operated in pipes through which various acids, alkalis and corrosive drains pass. They do not require constant Maintenance and, unlike taps and valves, pass through the solids contained in the working environment.
Gate valves as one of the types of valves
Gate valves are made of cast iron, ordinary or stainless steel, as well as non-ferrous metal alloys. The choice of material depends primarily on the contents of the pipe. Gate valves are used to temporarily block the flow and, depending on the principle of operation, they are divided into parallel and wedge.
Wedge valves have a wedge-shaped valve, the sealing surfaces of which are located at a certain angle. The spindle of this type of fitting is not retractable. A two-disk, elastic and rigid wedge is separated.
Gate valves are usually used for pipelines through which gas, water, oil and non-aggressive substances pass. An important point is that the working medium must be neutral to the valve material (for example, cast iron valves are used in gas pipeline systems).
Electric gate valves have gained popularity, because their control is possible both remotely and manually. The position of the locking mechanism is monitored by installed sensors and indicators.
Insertion into the pipeline is carried out by means of welding or flange connection.
Shut-off valve as a type of shut-off valve
With the help of a valve, you can completely shut off the flow of the working medium. It is not designed to regulate pressure in a pipe, and its position must always be either open or closed.
The design of the valve includes a spool located on the descending spindle. When he lowers himself onto the saddle, the flow is blocked. Based on the type of sealing, valves are divided into stuffing box, bellows and diaphragm valves.
Operation is carried out by means of manual or remote control. Cast iron socket valves are used for pipes in which air, water or steam is supplied, while temperature regime work should not be above fifty degrees. Union brass valves work in systems with high pressure and are not afraid of its drops.
Pipe fittings are widely used today. But not everyone has an idea what it is, why stop valves are needed in this system.
What will be discussed in this article is already clear from the title. Pipe fittings are the main key of the article. Today we will decide what this type of reinforcement is and what types of it are. Of course, from the point of view of professional engineers and plumbers, this type of fitting requires entire treatises for explanation.
But, most likely, since you are reading this article, then you do not need treatises, and the purpose of reading this article for you is to get the simplest explanation of this concept. This is what we will do next.
Shut-off valves are one of the varieties of pipeline valves, which actually proves the fact that you, for sure, have come across its elements in everyday life. The simplest and most obvious element of this type of fitting is an ordinary faucet, which is in your bathroom and kitchen. Using his example, we can talk about the main functions of valves - this is the regulation of the power of the flow of water (maybe another liquid or gas), as well as a complete blocking of the flow. We will talk in more detail about the functions and places of its application later.
Why is a shut-off valve needed?
Surely, after carefully reading the words that are given above, you already have some ideas about the expediency of shutoff valves. But, the purpose of this article is to maximize the disclosure of all issues that affect this topic, therefore, now we will answer this question in detail.
It is impossible to imagine any pipeline without taps. It doesn’t matter what will be distilled through these pipes (water, gas, and so on), in any case, it will be unrealistic to do without elements of shutoff valves.
For example, if there is no need for water flow, then we simply turn off the tap. And what do you think, how do the employees of the housing office act when a serious breakdown occurs? That's right, they also turn off the tap, but only on the riser. Thus, limiting the flow of water not in a single apartment, but in a number of apartments, and maybe houses. Representatives of the gas service do the same - they simply close the valve, thereby blocking its flow. Based on the functions of this type of pipeline fittings, its importance is extremely difficult to overestimate.
Remarkably, it comes in different varieties and is not limited to ordinary cranes.
Types of valves
There are two main principles, thanks to which it made sense to develop a large number of types of this reinforcement.
1. Resources transported through pipes.
You don't need to be a great physicist to understand that an ordinary faucet, which we can observe in our kitchen or bathroom, is not able to cope with the flow of gas. And here very simple reason- density difference. For example, if an ordinary faucet can stop the flow of water, then a gas that has many times lower density will certainly find a “slit” and leak out. Based on this principle, the varieties of valves can be divided into three groups (these are the main ones, there are more of them):
1) Shutoff valves for water pipelines;
2) Stop valves for gas pipelines;
3) Stop valves for oil pipelines.
2. The second principle of separation of this type of pipe fittings is pressure. A simple example can be given. An ordinary faucet that is in your kitchen is designed for low pressure, which is not strange, given the diameter of the pipe. But if such a crane is installed on the highway, then the flow of water will simply blow it away, and there will be no sense from such a crane. Based on this principle, valves are divided into:
1) Shut-off valves designed for low pressure
2) Shut-off valves designed for medium pressure
3) Shut-off valves designed for high pressure.