What is distribution fittings

Types of distribution devices (RU)

Delivery of electrical energy to consumers requires the organization and installation of an appropriate material and technical base, the most important elements of which are distribution devices. Let's consider the main types of switchgears, their purpose and characteristics, connection procedures and requirements.

Purpose of distribution devices

Distribution devices are electrical installations that receive and distribute electricity during its delivery to consumers. In addition to delivering energy to its intended purpose, switchgears are used to supply voltage of appropriate characteristics to the equipment of electrical installations and switching systems.

Classification

There are several classifications of reactor plants based on various features. Depending on the operating conditions, there are switchgears (to enlarge the diagram, click on it):

• open type (OPU) – equipment located outside buildings or other shelters. Such devices are easy to check for serviceability, easy to locate and make changes, but they take up a lot of space and require increased protection from the adverse effects of atmospheric and climatic factors; outdoor switchgear
• closed type (CLU) – are located in protected facilities and take up much less space. The disadvantage is that it is difficult to maintain due to its more compact location. Typical for the conditions of an industrial enterprise or city. ZRU

about outdoor switchgear:

The specified RUs may differ according to the following criteria:

• division method - in the form of separate sections or with bus systems. Bus systems can switch consumers from one section to another. If separate sections are performed, the consumer is connected personally;
• device connection diagram - ring and radial method. With a ring circuit, one object is connected to several switches. If a radial circuit is arranged, consumers are powered through busbar disconnectors using one switch. The radial method is simpler, and the circular method is more reliable and practical for ensuring the operation of electrical equipment;
• the presence of bypass elements - this system allows you to repair equipment without disconnecting subscribers.

In addition to the listed varieties, SF6 equipment is used, which involves placing the installations inside a space filled with a special composition with high safety properties.

Design – switchgear

Also used are complete switchgears (SGD), consisting of standard modules placed in cabinets. Such elements contain the necessary safety blocks, switches and other components and are supplied ready-made, which does not require packaging. If the device involves outdoor installation, it is called KRUN. Such a module provides appropriate protection.

KRUN

about KRU:

Depending on the voltage class, network parameters, number of subscribers, the following distribution devices are provided:

• prefabricated chambers;
• complete distribution devices;
• points for maintaining commercial records;
• complete transformer substations;
• points for automatic voltage regulation;
• distribution board panels;
• low-voltage distribution panels;
• outdoor electrical energy metering cabinets for private homes;
• devices for monitoring parameters.

More details about the features of the switchgear according to voltage characteristics.

You can find more information about RU in this book (about RU from page 392): Open book

RU up to 1 kV

These elements are completed and placed in special cabinets or panels. Their purpose may include transmitting energy to consumers or powering their own equipment.

In addition to the main systems, such modules can be equipped with additional devices:

• current transformers and electrical energy metering devices;
• indicating circuits and position indicators of switching switches;
• measuring units to determine the technical characteristics of circuits;
• signaling and protective devices against ground faults;
• devices for automatically switching on backup circuits;
• remote control systems.

Low-voltage switchgear may include DC modules that distribute voltage from power sources to equipment and consumers.

High voltage equipment

These systems are designed to operate elements under voltage conditions above 1 kV.

RU can be equipped in cabinets divided into separate compartments with current transformers, outgoing cables, busbars, withdrawable parts and secondary circuit compartments.

Individual compartments are securely insulated to ensure safe operation. In withdrawable modules, taking into account their purpose, switches, voltage transformers, arresters, and auxiliary transformers are located.

The location of the retractable element may include being in a working, control (disconnected) or repair position. If the device is in operation, the main and auxiliary circuits are closed. The control position is characterized by an open state of the main circuits and a closed state of the auxiliary circuits. In the repair position, both circuits are opened and the pull-out element is located outside the cabinet.

Busbars of current-carrying elements are made of aluminum or alloys based on it. When using large currents, copper elements are used, and if the rated current is within 200 A, steel elements are used.

The safety of the equipment is ensured by appropriate locking systems. Curtains and fences are used to cover the deflated pull-out element and prevent the possibility of turning on the equipment in this state.

Proper use and configuration of distribution devices ensures a reliable supply of energy to consumers within the specified parameters and safe operation of power equipment.

Source: https://ofaze.ru/teoriya/raspredelitelnye-ustrojstva

Types and purpose of shut-off valves

Shut-off valve products belong to a special type of products for pipelines, the purpose of which is to quickly regulate the flow rate of the working medium to ensure the specified parameters of the technological process.

The action of shut-off valves is aimed at closing, opening, changing the direction and speed of movement of the working gas/liquid.

In addition, shut-off valves should include drainage and control products that serve to discharge media from pipeline systems, technological devices, and supply media to control and measuring instruments.

Fittings of this type are present in all pipelines of industrial production, technical facilities for domestic purposes (heating, gas, water supply, sewerage, etc.), and make up at least 80% of the total number of products used in the pipeline. The most common types of shut-off elements are valves, valves, taps, flaps and closures.

The choice of materials from which these parts are made is currently quite wide:

• metals (titanium, aluminum);
• alloys (cast iron, steel, bronze);
• polymeric and synthetic materials, for example, polyvinylidene fluoride (PVDF), chlorinated polyvinyl chloride (CPVC), polyethylene (PE), polypropylene (PP).

When choosing a shut-off product, one is guided by the following technical characteristics: connecting diameter, purpose and material from which the body and working part of the pipeline are made, closing speed. Special requirements: long service life, high strength, reliability, safety, corrosion resistance of the material to the working environment, tightness, ease of installation and ease of operation.

It should be noted that the working environment of the pipeline quickly damages shut-off valve products, abrasion of sealing elements, wear, and corrosion processes occur, therefore it is necessary to carry out timely technical control of equipment, flushing of pipeline systems, repair or replacement of the product.

Depending on their purpose as part of a technical object, shut-off valves are divided into categories:

• industrial (general industrial, special) – used in production of various types of activities, including the national economy;
• ship - operated in the given specific conditions of sea and river transport;
• plumbing – pipeline fittings for household use, used in gas stoves, water heaters, bathrooms, boilers, etc.;
• custom manufactured – designed, manufactured and operated in accordance with specific specified technical requirements, for example, in unique, experimental industrial facilities.

The functions performed by this type of valve are extensive: control, distribution and mixing, safety, protective, shut-off, phase separating.

In this article we will consider the types of shut-off valves, the action of which is aimed at changing the cross-sectional area of ​​the pipeline to regulate the flow rate of the medium or stop it completely.

Gate valve

The main difference between this part is that the locking (regulating) element is a sheet, disk or wedge that can move back and forth in a direction perpendicular to the direction of movement of the working medium.

This type of fittings belongs to the industrial category and is used mainly in pipeline communications of housing and communal services and industrial production.

Valves are divided into full bore and truncated, their design allows you to smoothly regulate the flow rate and prevent hydraulic overloads.

This type of product has a number of advantages: simplicity of design, wide range of operating conditions, short construction length, low hydraulic resistance, which is especially important when used in pipelines with high working fluid speeds. The disadvantages of valves are determined by their design: a fairly long time spent on closing or opening the valve element, wear of sealing parts, difficulty in maintenance.

The domestic industry produces valves with a non-retractable stem and a retractable spindle. Valves are installed regardless of the direction of flow in the pipeline, since their design is symmetrical. They can withstand operating pressures from 2 to 200 atmospheres, the connecting diameter varies from 8 mm to 2 m.

Valve

A valve, as a type of shut-off valve, performs a regulating function and allows you to change the flow of media in the pipeline until its supply stops. With their help, a given level of pressure in the line is maintained and flows are mixed in the required proportion.

In the valve, the working element is located on a spindle, which performs reciprocating movements from the rotational movements of the flywheel. The spindle movement can be carried out automatically using servo drives or manually.

These products belong to the industrial category and are most often found in domestic housing and communal services. The most common type of valve is a straight-through valve, placed on straight sections of highways.

One of the disadvantages of this type of fittings, in addition to direct-flow valves, is the high hydraulic resistance, which limits their use in special technical facilities.

The advantages of valves are low cost, availability, reliability, ease of repair and maintenance during operation.

Ball valve

The difference in the design of a shut-off valve lies in its simplicity of execution: the shut-off element is made in the form of a ball, a cylinder and, which is quite rare, can be conical. Valves are either full bore or non-full bore. In full bore valves, the diameter of the bore always corresponds to the diameter of the connecting hole to the pipeline; in non-full bore valves, the bore diameter is correspondingly smaller.

The work is carried out in the extreme modes “closing” and “opening”. Its main function is aimed at blocking the movement of the work flow. Advantages, disadvantages and operating conditions are determined by the material from which the faucet is made.

For example, plastic taps PP and PE are resistant to aggressive environments, but are subject to the destructive effects of mechanical impurities in the working environment.

Stainless steel taps can withstand high operating pressures and temperatures, but from the point of view of domestic use they have a significant cost.

Valve

Valves (check valves) belong to the protective pipeline fittings, functionally designed to prevent the reverse flow of the working medium in the technological scheme. By passing the working medium in one direction, the valves do not allow the return flow of liquid or gas.

With their help, various production equipment (pumps, tanks, devices, etc.) are protected, and the damaged section of the pipeline during working media leaks is excluded from the overall technological process, which is extremely important in the event of an emergency.

There are valves with a spherical or cone-shaped locking element design, the movement of which occurs in a direction parallel to the movement of the carrier.

The flow passing through the valve's operating window presses the shut-off element to the base of the device, which stops its movement in the opposite direction. Check valves are manufactured both built into components and assemblies, and in independent form.

As a rule, check valves are mounted on horizontal straight sections of pipelines in the direction of the working flow.

The valves, having a relatively simple design, nevertheless provide reliable and tight shutoff of the working flow, due to which they are widely used for gaseous and liquid working media. They are used in a wide range of pressures (from 5·10-6 to 2000 atm.) and operating temperatures (from minus 200 to plus 600°C). Suitable for pipeline structures of relatively small diameters.

Gates

A valve is a shut-off device used to provide a tight seal when shutting off a working flow. Can operate in “regulation” and “overlap” modes. It is the most convenient and simplest type of shut-off valve for maintenance and operation, has a low cost and market availability.

The shutter device is designed in such a way that the locking element rotates around the axis on which it is located. The most common type of this device with a disc valve is the “Butterfly”.

The shutter position can be controlled manually using a handle and mechanically using a gearbox or electric drive. Such advantages of Butterfly butterfly valves as ease of maintenance, installation and replacement of sealing parts, small construction height and weight, as well as long service life and affordable cost are widely used in domestic pipelines.

The domestic industry produces a wide range of shut-off pipeline valves that meet general and special requirements, high quality and modern technologies. The cost of such products can vary widely from 100 rubles. up to several tens of thousands of rubles, which is determined by the material, purpose, size, and manufacturer.

Source: https://pkfdetal.ru/info/11-vidy-i-naznachenie-zapornoj-armatury

Reinforcement - what is it? Types of fittings

The term “rebar” is often used in construction texts. This word is foreign, and its semantic content can cause confusion among people who are little familiar with the specifics of its use.

Rebar in construction

The industry concept of “reinforcement” can be divided into two large groups of meanings - structural and technological.

The first is used in the manufacture of building structures. Reinforced concrete differs from a simple monolith by the use of load-bearing rods, meshes or frames.

The fittings installed on pipelines distribute and regulate fluid flows in water supply and sewerage networks. These concepts are united by functional purpose. The fittings are what constitute the working part of the overall system.

Structural reinforcement

Concrete structures are the main type of building products. Concrete is sometimes called artificial stone. It has excellent resistance to compression, but is relatively easy to break when stretched and bent.

This disadvantage is eliminated by reinforcing the concrete mass with materials that have the ability to withstand tensile loads without loss of strength. The progressive development of the building materials industry has expanded the range of fittings offered.

In addition to traditional steel, it includes products made from polymers, such as composite reinforcement. The emergence of new materials makes it possible to more fully take into account the performance characteristics of products.

The use of materials and products for the construction of buildings and structures is strictly regulated. Safe operation requires compliance with standards developed by leading experts and approved by law. Steel reinforcement must comply with GOST 10884-94, which regulates the physical and technical parameters of the material. Composite meets the requirements of GOST 31938-2012.

Steel reinforcement entering the market, as a rule, meets technical specifications, since it has an established production base and technological culture. Unfortunately, elements made of polymer materials can have a significant variation in consumer properties, which requires careful attention to the purchased products.

In this case, preference should be given to enterprises that provide full specifications for them.

Steel reinforcement

The steel from which the reinforcement is made (GOST 10884-94) can be carbon or low-alloy. To improve adhesion to the concrete body, the rods can have a periodic profile, the parameters of which are also specified in the state standard. This type of reinforcement is the most common and well studied. Steel rebar is a traditional type of reinforcement material.

Concrete reinforced with steel bars, frames and meshes is called reinforced concrete. Almost all building structures are made from it, from foundation to floor panels and load-bearing elements of building frames. The factories produce a wide range of reinforced concrete structures for various purposes.

Today, monolithic construction is becoming increasingly popular, in which most building elements are manufactured in the design position by pouring concrete into installed formwork with laid reinforcement frame. If in the factory production of elements the main method of fastening the rods is welding, then in on-site production they usually use wire knitting of reinforcement.

In addition to periodic profile reinforcement, smooth bars are also used. Their adhesion strength to concrete or mortar is significantly lower, but in some cases the use of smooth-rolled reinforcement is justified.

Modern construction is evolving towards greater architectural expressiveness and lower costs. Polymer reinforcement allows you to do this most effectively. An important advantage of polymers compared to metal is their significantly lower weight and resistance to corrosion. These include basalt-plastic, carbon-fiber, fiberglass reinforcement.

The strength characteristics of polymer reinforcement usually exceed those of steel. Like steel, composite reinforcement can be of periodic or permanent profile. However, its operation under load has its own characteristics. Unlike steel, fiberglass reinforcement does not have fluidity, and when the maximum permissible loads are reached, the element instantly fails.

Steel vs composite: what to choose?

The nature of the work of reinforced concrete suggests the possibility of moisture affecting the reinforcement when cracks open in products working in bending and tension. Naturally, this increases the risk of loss of strength and reduces the service life of structures. When concreting or bricklaying in winter, steel is exposed to the aggressive effects of frost-resistant additives, which also creates the possibility of a decrease in performance characteristics.

Polymer materials make it possible to avoid the negative effects of corrosion on load-bearing elements of buildings and structures. Synthetic reinforcement ensures this. However, composites have worse fire resistance properties, losing strength faster when heated. The lower weight of reinforcement made of composites is an attractive property for individual and low-rise construction, which, as a rule, is not provided with lifting mechanisms.

The reduction in costs for transportation and movement around the construction site can amount to a significant amount.

Pipeline accessories

The range of applications for fittings in pipelines is very wide. It is used everywhere, from small-diameter networks in the private sector to massive industrial products. Pipeline fittings in distribution networks must meet high requirements for safety and trouble-free operation.

These network elements, combining conflicting requirements, can be very complex in configuration. For example, shut-off valves must withstand hydrodynamic shock, which reaches significant values ​​for large pipe diameters.

Therefore, non-ferrous metals, such as copper and bronze, are usually considered the most suitable material, allowing the production of milled and cast products of varying complexity. However, they have a high cost and low strength. Therefore, steel, cast iron and polymers are used as materials from which fittings are made.

The manufacturer guarantees the performance parameters of the products, which allows you to make an informed choice of a particular material.

Polymers in plumbing networks

The spread of plastic pipes has given rise to the emergence of fittings made of plastic or with a significant number of plastic components. They are most popular in public utilities and the private sector.

The undeniable advantage that such fittings have is their lighter weight and the absence of corrosion of pipes and network elements. Pipes made of polymer materials can be of almost unlimited length, in contrast to standard metal sizes.

They are quite easily connected to each other in various ways.

Welding polymers is less labor-intensive and fireproof compared to welding metals. In addition to the absence of corrosion, polymer pipes and fittings are not subject to the accumulation of sediment in water supply and heating networks, which can lead to overgrowing of the internal space and a decrease in the effective diameter. Shut-off valves, distribution and other, are installed on pipelines using methods used when making pipe joints.

Source: https://FB.ru/article/191333/armatura---eto-chto-takoe-vidyi-armaturyi

What is fittings? Types of fittings:

Many people, even those who have nothing to do with production, have probably heard the word “reinforcement”. However, not everyone knows what this product is.

The term “reinforcement” is a capacious concept that includes several definitions. They all vary depending on the area of ​​their use. Thus, fittings exist in construction, pipelines, and electrical engineering. What each of these concepts represents is worth understanding in more detail.

What is reinforcement

This word is of Latin origin and literally translates as equipment and weapons. In Russian, the term “fittings” is usually understood as all devices and parts that are not part of the main structure of any equipment, but play an important role in its proper operation.

In other words, fittings are a collective name for many auxiliary elements that are used for the normal functioning of any system. This concept includes building elements, switches, valves, valves and much more. Moreover, in each industry different parts of the system are considered as fittings.

Construction fittings

Builders are well aware of a product called reinforcement. What it is? Reinforcement is a rolled metal product that is most often used to increase the strength of concrete structures.

The scope of application of this type of rolled metal is quite wide. The fittings are used for:

• strengthening concrete building structures (foundation, walls, ceilings);
• installation of supporting parts of tunnels and bridges;
• production of welded structures (elements of stairs and other exterior parts);
• fencing production.

At the same time, for each type of work you need to choose a different type of steel reinforcement. This is very important, since all proposed types have special characteristics that must exactly meet the stated requirements for the finished object.

Assortment of construction reinforcement

Manufacturers now offer a wide selection of fittings, which differ in several parameters:

• Installation method: it can be knitted or welded.
• Production method. Construction reinforcement is produced in wire, rod and rolled form.
• Functions. Depending on the purpose, the product can be tensioned or non-tensioned.
• Profile type. According to this characteristic, reinforcement can be smooth, round or with a periodic profile.

In addition to the listed characteristics, the reinforcement differs in the cross-sectional diameter of the rod. The higher this indicator, the stronger and more reliable the product is. The diameter of the reinforcing bar varies from 6 to 80 mm, which directly affects the weight of the meter of reinforcement. For example, with d=20 mm, a linear meter of material will weigh 2.47 kg, and with d=40 mm - 9.87 kg. That is why, when choosing a type of rolled metal, it is imperative to take into account the technical requirements of each project.

Composite reinforcement

Over the past few years, in many areas of industry, conventional metal fittings have become less in demand, and products made from other materials have taken their place. This is nothing more than composite type reinforcement. What is she?

Composite reinforcement is rods that are made not from a metal alloy, but from various fibers (basalt, glass, carbon and aramid), which are held together by composite compounds. In other words, this is a general concept that includes several types of material.

Kinds

Depending on what fibers were used in production, composite products are divided into several categories:

• Basalt-plastic. These rods can be recognized by their natural black color.
• Fiberglass. Fiberglass reinforcement has a characteristic light yellow color.
• Aramid.
• Carbon fiber.
• Combined. Such options are made based on several types of fibers.

It is worth noting that fittings of this type can be used almost everywhere where a metal analogue is used. However, before purchasing, you should study its characteristics in more detail.

Advantages of composite type products

Composite reinforcement has noticeably replaced traditional metal reinforcement, and this is understandable. The fact is that this material has several advantages that make it simply irreplaceable in certain areas of industry.

• Increased tensile strength. Compared to metal rods, fiberglass products of the same diameter have an indicator 2.5-3 times higher. This allows you to replace the diameter with a smaller one, but with the same tensile strength.
• Light weight. The weight of fiberglass and other types of composite rods is 12 times lower than metal rods with an identical diameter.
• Low price. By purchasing a composite product you can save up to 20-50% of the cost of metal rods needed to perform the same amount of work.
• Possibility of folding into coils. Fiberglass reinforcement can be easily rolled into coils. The advantage here is ease of transportation. Unlike metal rods, coils can be easily and quickly transported even in the trunk of a car, without specially renting a vehicle.

Disadvantages of composite products

Despite the large number of advantages, composite building reinforcement also has several disadvantages. For this reason, before purchasing reinforcing elements, a careful calculation of the reinforcement should be carried out.

• Low modulus of elasticity. Metal and fiberglass products of the same cross-section have different elastic modulus. For the latter, the figure is 4 times lower.
• Exposure to high temperatures. When heated to 90-100 degrees Celsius, the connecting elements of composite reinforcement melt, making the product more fragile. In this regard, you need to take care of additional thermal protection.
• Inability to use electric welding. To solve this problem, reinforcing bars are installed at the ends of the rods on which welding can be done.
• Cannot be bent. If you need to give the rod one or another curved shape, then it will be impossible to do this on the construction site. The only way out is to manufacture the required shape at the factory.

Pipe fittings

By this term, some people understand metal rods that are used in the construction of pipelines. However, this is a misconception. What are pipeline fittings? This name hides equipment that is not part of the main composition of the pipeline, but is involved in regulating its operation. In other words, these are valves, plugs, mixers, adapters and other elements.

Depending on the purpose of using the reinforcement, it comes in several types:

• Shut-off valves. Necessary for blocking the flow of the medium (these are valves, valves, flaps).
• Regulating - used to regulate parameters such as flow, pressure, level in vessels (such fittings are represented by valves and regulators).
• Shut-off and regulating – combines the capabilities of two types of devices.
• Distribution and mixing - is responsible for the distribution of flow (these are distribution and mixing valves, distribution taps).
• Phase separation - separates media that are in different phases (air vents, condensate traps).
• Safety (fuses).
• Test.
• Drain fittings.
• Connecting - thanks to these parts, individual parts of the pipeline are connected (these are clamps, adapters, couplings).

All existing parts of this type are usually divided into household and industrial. Similar parts of household and industrial types have a similar structure, but the latter are distinguished by increased power, size and wear resistance. This is explained by the fact that industrial pipeline networks are operated under more severe conditions, and therefore the requirements for fittings are increased here.

The goods market offers a wide range of domestic and foreign products, so there will be no shortage of choice.

Electrical fittings

In addition to construction and pipeline fittings, there are also electrical fittings. What is this? This term usually refers to various auxiliary devices used in electrical networks.

As a rule, this type of device represents standard elements that are used to secure the main electrical components and control their correct operation. The main part of electrical fittings is:

• shields;
• switches;
• cartridges;
• some machine parts.

These equipment parts themselves are auxiliary, but their breakdowns directly affect the quality of operation of the entire electrical network. That is why valve inspections must be carried out regularly.

Having familiarized yourself with what reinforcement is and what types of it exist, you can come to the conclusion that this is a fairly capacious concept that includes many auxiliary elements. The correct operation of the entire system depends on them. In order to choose the right type of equipment, it is very important to study in detail the range of proposed elements and their technical characteristics.

Source: https://www.syl.ru/article/355522/chto-takoe-armatura-vidyi-armaturyi

Translation – pulp polyp – from english – to russian

Mixer Cylinder. or barrel-shaped steel with fireproofing. lined vessel with a capacity of 600-2500 tons for accumulation, leveling of chemical. composition and temperature domain. cast iron, intended for processing in liquid form in steelmaking units. M. was first used in 1889 by Amer. metallurgist W. Jones, m.

ensures uninterrupted operation of steelmaking shops. In the so-called active m. cast iron is heated by fuel burners or induction. heaters, certain impurities are partially removed from it (mainly sulfur), the m. has a neck for pouring cast iron from the ladle and a special “spout” for draining cast iron into the ladle when it is tilted. mechanism.

In Russia, the most common. m. with a capacity of 1300 tons.

[http://metaltrade.ru/abc/a.htm]

FR

microwave mixing device A microwave device designed to obtain combination frequencies in the spectrum of the output signal when two or more signals differing in frequency are applied to the inputs.

[GOST 23769-79]

Invalid, not recommended

• impeller
• mixing device

Interfloor ceiling in a house made of aerated concrete

› Roofing

18.01.2020

Options for the interfloor floors of a house made of aerated concrete blocks provide for the correct ratio of the weight of the structure and the strength of the load-bearing walls of the house; the balance of the strength of the floor and the rigidity of the structure is also taken into account. In addition, no less attention is paid to the factors of noise insulation, fire resistance and heat preservation ability.

A reliable and durable floor for an aerated concrete house that meets generally accepted standards can be made of three types - slab, wood beams or metal beams, and a monolithic type floor.

What is a monolithic floor?

First, let's understand the properties of aerated concrete and the principles of constructing houses from this material.

Cellular concrete blocks are made from a mixture of lime, cement and sand, into which an aluminum-based chemical, a foaming composition, is added. Aerated concrete is made both by an autoclave method by actively influencing the solution poured into block molds using steam and pressure, and by a non-autoclave method. The gradation of its quality and price depends on this.

Aerated concrete requires a special approach, because the cellular structure of the blocks minimizes the strength properties and the ceiling is constructed taking this circumstance into account .

It is necessary that the weight of the structure pressing on the load-bearing supports be compensated by belt-type reinforcement, creating the rigidity of the load-bearing walls. The reinforcement is placed at the bottom, at the top and in the center, protecting the aerated concrete blocks from the pushing effect from the ceiling.

The ceiling itself is also supplemented with reinforcement.
Sections of load-bearing walls must be accurately measured for deviation from a strictly horizontal line, but if such a problem does occur, then aerated concrete makes it easy to correct the situation by sawing the material.

Monolithic slab

A monolithic floor in a house made of aerated concrete is placed on beams with different cross-sectional sizes covering the entire surface area. Its most important part is a frame with a reinforcing function. Metal rods with a small cross-section are fastened with wire into a single reinforcing system. It is this that will bear the greatest load, giving the concrete literally “iron strength.”

Concrete is ordered ready-made from companies specializing in the sale of building materials, or it is made independently. When manufactured independently, mixers of small dimensions are used, which reduces the quality of the design, since there is a high risk of mixing volumes of concrete with different composition ratios , which will create heterogeneity of pouring and reduce strength.

Prefabricated monolithic floor

You can use both the monolithic covering method and the method of covering aerated concrete using the prefabricated principle. This is a subtype of the monolithic method. It is suitable for a building consisting of one or two floors.

The interfloor space is “stitched with beams” at intervals of 60 cm. Polystyrene concrete or expanded clay blocks are laid out on them, acting as both formwork and part of the floor.

Concrete solution reinforced with reinforcement is poured on top and left until completely dry.

Finished slabs

Flooring made from slabs with voids is suitable if you are willing to spend a lot of money, since both the slabs themselves and their installation, which requires renting equipment for lifting, are more expensive . In terms of price, the situation becomes less burdensome if there is a factory nearby that produces such slabs, since you can order directly from the manufacturer, and the delivery budget will be quite acceptable. In this case, the project will cost even less than a monolithic one.

In what cases are monolithic and prefabricated-monolithic methods combined?

Prefabricated monolithic type ceilings impose certain regulations on the parameters of the building itself in terms of length and width, and the location of load-bearing walls.

This is dictated by the standard dimensions of the slabs and the fact that the slabs require support on supporting structures. That is, it is necessary to adjust the house plan and the arrangement of rooms in accordance with the standard dimensions of hollow-core slabs.

The support is made by the opposite sides of the slabs on the load-bearing walls. It is unacceptable to lay slabs on three walls, since this circumstance will incorrectly distribute the load on the foundation of the house , which in the case of aerated concrete is categorically unacceptable.

In overlap areas where it is not possible to place slabs, monolithic fragments are constructed. This usually happens due to the reduced area of ​​the house, or in places where the ventilation system shafts from the bathroom or kitchen area are located.

The monolithic method of creating an interfloor divider is more convenient and multifunctional; it does not limit the planning of rooms and the ratio of the length and width of the building.

Material, tools and technique

• To work, you will need to order mixers with concrete, a concrete pump (if you need to lift the mortar to a height), and a construction vibrator for the mortar. Also, if the concrete mixture is not purchased, but is made independently, then use a concrete mixer.
• For reinforcement it is necessary to purchase special metal rods and knitting wire, and for formwork - wooden beams, boards and moisture-resistant plywood.
• For pouring, you will need ready-made concrete or its usual components in the form of cement, water, purified sand and small crushed stone 5-20 mm.

The transition from the process of erecting walls to creating a floor slab occurs at the stage of completely bringing them to the intended height. They start with formwork.

How to make formwork?

First, formwork is made, which looks like a huge bathtub mold for subsequent filling with cement mortar . It is constructed from moisture-resistant plywood sheets and vertically installed support parts.

Instead of wooden beams, special telescopic metal tubular racks can be used as supporting elements. And instead of plywood sheets, you can take boards, laying them out according to the same principle.

Supports for the formwork are placed based on the strength that would support not only its weight, but also the concrete poured there, coupled with the weight of the reinforcement component.

So, the sequence of work on formwork for a monolith:

• Construction of supports. Here you need to check the level very carefully, since even a slight deviation in height will have a detrimental effect on the strength. Each rack assumes a load from a minimum of 300 kg to an optimal of half a ton.
• An indentation of 20-25 cm is made from the walls, a meter distance is maintained between the racks.
• Laying beams across the proposed floor slab, they are attached to the walls and sewn in those places where they come into contact with the posts to create maximum stability and stability during pouring and drying.
• The size of the beam is selected such that the concrete mass does not create a deflection in the bottom of the formwork beyond the permissible measure of 1/150 of the span.
• Boards or plywood sheets are laid on the created base , which are additionally insulated with film. The gaps between the boards can also be foamed for greater reliability.
• At the same stage, pipes for electrical wiring and ventilation are laid.
• The formwork is ready and you can proceed to the construction of the reinforcing mesh.

Requirements for fittings

• Take metal rods with a cross section from 8 mm to 10 mm.
• They make a mesh, fastening them with wire no more than one and a half millimeters in cross-section and no less than 1.2 mm.
• The reinforcement is placed on two levels - on the upper tier, creating a tensile effect, and on the lower, working on compression.
• Indentations are made between the reinforcing mesh and the formwork of 20-25 mm in order to maintain the optimal thickness of the concrete layer in these overlap areas.
• The upper tier of reinforcement should be at a distance of 100 mm from the lower one.
• The resulting gap is equipped with distance clamps with support legs.
• A rod with a cross-section of 10 mm can, if necessary, be increased by no more than 480 mm.
• Reinforcement rods in tiers are fastened according to the checkerboard principle.

How to reinforce

1. The lower part of the reinforcement is laid longitudinally, and on top of it a transverse row of rods is installed in two-meter increments.
2. The third row is again laid longitudinally, adhering to a meter step.
3. Take a wire with sufficient softness and go through all the intersections of the rods, carefully tying them together.
4. Plastic clamps are attached to the bottom layer of reinforcement at an angle of 15° at a meter distance from each other.
5. So the lower tier is filled with reinforcing mesh and after that they begin to create the upper tier using exactly the same principle.
6. Every 40 cm, the edges of both tiers are fastened with special connectors.

Read more: Fence made of forged elements

Pouring concrete

Requirements for strength, quality, thickness:

• It is permissible to use only high-quality concrete; usually M200 or even better materials are used. The quality of concrete is the key to the required strength of the floor.
• The thickness of the slab is calculated from a minimum of 15 cm to a maximum of 30 cm.
• Filling should not be done at temperatures below +5°C. If the situation leaves no choice, then the composition is supplemented with special additives and the solution is heated before use.

1. Mark the fill height.
2. The procedure itself takes place in one go. The full volume of concrete is continuously poured into the mold using a concrete pump. Otherwise, if poured in several stages, the ceiling will lose strength.
3. The concrete is leveled to the shape of the formwork.
4. Be sure to use a construction vibrator to remove air bubbles from the composition. You can't do without vibration work. The gravity of the concrete itself is not sufficient for the required compaction; it is necessary to subject the composition to vibration, since only in this case will it be compressed to the required standard and adhere together with the reinforcing mesh.

After complete hardening, construction work is resumed.

Advantages and disadvantages of this type of overlap

• The load-bearing function is many times higher in quality than when using beams.
• Freedom in building planning, both in terms of aspect ratio and building shape.
• The durable type of flooring is well suited to the specifics of aerated concrete.

• Both the work itself and the drying process take a lot of time.
• You need special equipment and technical equipment.
• An accurate load calculation is required to determine the parameters of a monolithic slab.
• The cost of the project will be significantly higher than using wood.

• To strengthen the upper part of the walls, in order to compensate for the load from the slab, a reinforcing belt is laid out, a continuous structure along the entire contour of the building.
• To check the concrete for drying, you need to put a piece of roofing felt on top and check it after a few hours. If the material from the inner part is moistened and has condensation, then the monolith is not ready yet, but if it is dry, then the hardening is complete and successful.

Having familiarized yourself with all the nuances of constructing an interfloor monolithic slab for an aerated concrete house, you can choose to take a balanced approach to the choice of roofing method, weighing the pros and cons, estimating your capabilities in terms of time and budget.

Source: https://iv-proect.ru/krysha/mezhetazhnoe-perekrytie-v-dome-iz-gazobetona.html

Electrical wiring diagrams in a private house: self-installation according to instructions

A modern home is a network of communications, the intersection of all kinds of wires, pipes of various diameters and cables, each of which has its own purpose.

The uninterrupted functioning of household electrical appliances and intra-house communications depends on the reliability of the electrical network. Its installation and switching must be entrusted to a specialist electrician.

But, given that the process is simple, someone with basic knowledge of the functioning of the electrical network will be able to install electrical wiring in a private home independently.

DIY electrical wiring installation

The construction of the house is carried out in several stages. The installation of communications begins after the box - walls and roof - has been erected. Wiring installation is carried out in accordance with a pre-drawn step-by-step diagram. When you have doubts about your own abilities, you need to invite a professional.

You need to have a simple set of tools and know how to use them. Compliance with safety precautions is mandatory. For work you will need electric and manual tools and protective equipment:

• angle grinder (grinder);
• wall chaser for selecting grooves in concrete and brick walls;
• hammer drill for drilling through holes in walls and selecting mounting grooves and holes;
• wire crimping pliers;
• insulation stripper for stripping cable ends;
• hammer, pliers, side cutters;
• screwdrivers, knife for working with wires;
• a reliable stepladder for mounting lamps and chandeliers;
• protective gloves and a respirator if you plan to cut grooves.

Step-by-step instruction

Installing electrical wiring in a house involves a sequence of actions. Before getting down to business, it is imperative to develop an action plan, divide all work into successive stages and strictly follow the plan.

Also, at the stage of creating step-by-step instructions, it is necessary to create a list with an approximate list of necessary accessories and consumables. The exact amount of material that is purchased for moldings will become clear after marking the walls and taking measurements.

Circuit markup

Work begins with surface marking of laying places, cable switching, points of single intersection of communications, installation areas of circuit control elements and electrical distribution points: switches, sockets, chandeliers, lamps, junction boxes, panels. It is convenient to mark with colored chalk - highways are indicated by one color, fittings - by another.

After the diagram is transferred from paper to the walls, “bottlenecks” will be discovered - points of intersection of electrical wires with other communications: heating water pipes, ventilation gutters, etc. Contact of conductive elements with metal components of intra-house communications is strictly prohibited. Places of possible contact and areas inconvenient for work can be bypassed and, if necessary, moved.

It is impossible to save on laying cables using the “shortest route”; it is customary for electricians to lay hidden lines from sockets and switches horizontally and vertically; this will help in the future to facilitate the installation of decorative elements and household items mounted on walls: paintings, cabinets, shelves, mezzanines.

Wall work

The volume of chiselling work depends on the type of wiring being laid in a brick house: it can be open or hidden. Chiseling, the most labor-intensive and traumatic part of the activity, involves working with electric tools.

It is necessary to observe safety measures: use protective equipment, take a stable position while working, using cutting and chiseling tools above floor level, use stable ladders, reliable stepladders, scaffolding. It is better to bypass narrow and inconvenient places for working with power tools.

Open wiring

If the power supply to a private house is carried out over the walls, it is necessary to select holes for embedded elements in which the wires will be laid - cable channels, corrugated pipes, brackets, baseboards. The open type of wiring is considered less labor-intensive, but its significant drawback is the disruption of the aesthetics of the premises by external electrical installation elements.

Hiding wiring with plasterboard panels leads to a significant loss of volume in residential premises. For open installation, it is necessary to use special corrugated pipes and cable ducts made of non-flammable plastics.

Closed wiring

When electrical wiring is carried out in channels specially selected for this purpose in the thickness of the walls, it is called closed. Carrying out the preparatory part, you will have to make a lot of noise and create dust: making grooves in the brick for the wires and using a core drill to select holes for mounting internal sockets and switches is a difficult task. The laboriousness of the process is justified by the end result - the beautiful aesthetics of the interior upon completion of the renovation.

It is impossible to electrify a wooden structure (a log house or a structure made of timber) in a closed way; laying wires in the thickness of the tree is strictly prohibited. In order not to spoil the aesthetics of the premises, retro installation is used as an option - twisted wires are fixed on special porcelain insulators. Sockets and switches are installed on dielectric porcelain pads. Junction boxes must be fireproof.

Preparing the wires

Before wiring, you need to decide on the material of the wires: copper or aluminum. It is advisable to lay main carriers of the same type; the copper-aluminum strands will heat up and weaken. In damp rooms (bathrooms, basements) the situation will be aggravated by oxidation. In cases where it is necessary to connect different metals, special mounting strips or tubular connecting crimp lugs are used.

Before purchasing cables, you need to make lists of group consumers (electrical appliances that will be located in each room) and calculate their total power. This will help the sales consultant suggest wires of the required cross-section. Excessively thick - not needed, because... will greatly increase the estimated cost of wiring in the house. In addition, they are much rougher and inconvenient to work with.

Which ones to choose

You shouldn’t be zealous and buy something overly fashionable and technologically advanced - just choose non-flammable conductors with double insulation (brands VVG, PVG) and a cross-section from 3 to 5 mm.

Input cable

The cable that powers the house from the overhead line is called the input cable; it must withstand the total load of the connected facility. The input cable is laid from the power line pole to the input panel. Installation to the panel is carried out independently; it is connected to the power line by a specialized team of electricians.

The self-supporting insulated wire (SIP) used to make the input comes in cross-sections of 10.16 and 25 mm. The SIP is fixed with special tensioners; its stripping and switching by twisting is not allowed; piercing clamps must be used.

Grounding

A grounding loop is required to minimize the risk of electric shock to people. Modern facilities use three-pole sockets with a grounding pin connected by a grounding conductor to the circuit.

How to make a grounding loop in a private house

The grounding loop consists of metal pins (electrodes) driven into the vertices of an equilateral triangle drawn on the ground. At the soil level, the electrodes are welded together using rolled wire. The grounding circuit must comply with the operating rules for electrical installations.

The distance between the electrodes and their depth depend on the electrical conductivity of the soil in which the circuit is installed; Installation values ​​must be clarified with the service organization. After installation, the electrical laboratory tests the circuit for compliance with standards.

Residual current system and circuit breaker

In the electrical wiring diagram in a private house, 2 types of protective devices against electric shock are used:

1. RCD - residual current device. Cuts off the line in case of leakage.
2. RCBO - residual current circuit breaker. Shuts down in case of leakage, overloads and short circuits.

RCBO is a complex and expensive device, which, in addition to its purpose, also performs the functions of an RCD. For a private house, installing an RCD will be sufficient.

Distribution boxes

Distribution boxes are necessary for arranging connections of electrical wires and distributing lines leading to electricity distribution facilities. In boxes, wires can be connected by twisting or fixing with bolts on special mounting strips. The boxes limit accidental access to connections and prevent the spread of fire in the event of overheating of connections and short circuits.

Installation and switching of cables and structures

Electrical wiring in the house is connected to each other using the following method:

1. Soldering. Soldering is not used for in-house installation; it is an expensive and labor-intensive process.
2. Twisting. The easiest way to install wires from the same material. Copper and aluminum cannot be twisted - the connection will heat up.
3. Connections on terminal blocks. Reliable, simple and inexpensive installation method. Terminal blocks of various types, shapes, types and sizes greatly simplify installation.

Connecting lighting sockets

Electrical wiring in a private house with your own hands should eliminate confusion: each wire, zero-phase-ground, must be in its place, they cannot be confused. To prevent this from happening, you should focus on the difference in the color of the cores.

Switchboard

All wires converge to the switchboard: power input from outside and group consumers from inside the house. You need to equip the switchboard with cut-off machines yourself. The number of machines must correspond to the number of group consumers. It would not be superfluous to provide backup machines.

To facilitate switching and prevent errors when changing installation, the ends of the cables must be marked with temporary nameplates (markers with a mark on the purpose of the wire); they can be secured to the end of the wire with cable ties or duct tape. After installation, the information from the nameplates is transferred to a plate fixed on the switchboard door.

Testing and commissioning

Electrical laboratory specialists check the functionality of the installed in-house electrical network. After the tests, a protocol is written and a report on the test results is issued. If the test wiring did not pass, the report will indicate a list of shortcomings that need to be eliminated. After they are eliminated, the check is repeated.

Conclusion

Based on a clearly drawn up action plan, it is not difficult to carry out electrical wiring in the house with your own hands. It is worth paying maximum attention to creating a plan and considering each of the stages of the proposed work.

Even the smallest details need to be written down on paper. If possible, you should consult with electrical specialists or friends who have independently installed electrical wiring.

Watch also the video on how to make electrical wiring yourself

Source: https://vodatyt.ru/elektrika/v-chastnom-dome.html

Pipe fittings: types and purpose

Pipeline fittings are distinguished by a wide variety of models, which is reflected in its classification. According to regulatory documents, all types of reinforcing products are divided into separate groups, similar in their functionality, design principles, and materials. Let's consider their main varieties found in modern production.

Types of pipeline fittings

The main principle on which this classification is based is functional purpose. Depending on it, the following types of fittings are distinguished:

• constipation;
• disconnecting;
• reverse;
• regulating;
• safety;
• distribution and mixing.

Shut-off valves

Serves to hermetically shut off the flow of the internal environment of the pipeline. It is one of the most common types of fittings due to its functionality. An indicator of its quality is the tightness life, on which the service life of the locking device directly depends.

The main operating states of reinforcement products of this type are the “open” and “closed” positions, and their design does not provide for any intermediate positions. The scope of application of shut-off valves is incredibly wide, since it is needed almost everywhere where there are pipelines.

First of all, these are the oil and gas industry, nuclear energy, sea and deep-sea vessels, aviation, spacecraft and much more.

Shut-off valves

This type of fittings is also called protective, since it serves to stop the internal work flow when the normal load is exceeded. The operation of such devices is ensured by turning off a specific sensitive element.

Check valve

Provides the desired direction of the flow of the working medium, preventing it from flowing in the opposite direction.

Control valves

Serves for the correct organization of technological processes by precisely regulating the characteristics of the working environment. Together with shut-off valves, it creates conditions for the uninterrupted operation of equipment, which is very important for strategic facilities such as nuclear power plants.

Safety fittings

Designed to protect equipment from emergency excess of load standards. The operation of safety valves is based on the release and release of excess working fluid. Thanks to the installation of such devices, high reliability of pipeline equipment and its trouble-free operation are ensured.

Distribution and mixing fittings

Necessary for the correct distribution of work flows in individual areas and their mixing, if necessary. It is also available in an isolated version, for example, only for distribution or mixing.

In addition to the listed types of pipeline fittings, there are also combined products that combine several functions in their design.

Types of pipeline fittings

In addition to the main classification, there are also several types of reinforcement, the membership of which is determined based on the design features. There are four main types:

• valve - has a perpendicular stroke of the working element relative to the flow axis;
• crane - the movement of the working element occurs around its axis;
• valve - the locking or regulating part moves parallel to the axis of the working flow;
• disc valve - a disc-shaped element that rotates around an axis that is perpendicular or another angle to the direction of the working flow.

All these types also have a more detailed classification, depending on their design features. For example, gate valves are divided into parallel and wedge gate valves, with rising or non-rising spindles. In the category of valves, there are ball, cone and cylindrical designs. Valves, depending on the number of seats, can be single- or double-seated, and depending on the shape of the valve, they can be needle-shaped or disc-shaped.

The design features of each of the listed types determine their areas of application. For example, valves that operate rather slowly are more suitable for shut-off valves.

Valves, on the contrary, are characterized by fast response and high tightness, which makes them more preferable for control devices.

Taps and butterfly valves have mixed technical characteristics and can act as both regulators and shutoffs, depending on their purpose.

Other types of pipeline fittings

Along with the main classification, there are many other types of reinforcement, the systematization of which also occurs according to similar design or functional characteristics. Let's look at the main ones.

By scope and purpose

One of the classification parameters is the operating conditions of the valves - vacuum, cryogenic, etc. Other signs for separation are the installation location in the main equipment, the presence of additional functions, and the operating features of the device. However, the most extensive division of pipeline fittings is by purpose:

• control;
• reduction;
• trial run;
• anti-surge;
• drainage, etc.

The use of reinforcing products in a particular industry imposes a number of specific requirements on them. For example, for installation on oil pipelines, fittings that are resistant to corrosion are required, and for use in gas pipelines, they need to have a high degree of tightness. In the chemical industry, where the working environment can be even more aggressive, the requirements for the stability of the valves will be even higher.

According to the design and shape of the body

The position of the pipes determines the division of the fittings into the following types:

• pass-through - the directions of the pipes are parallel or coaxial;
• angular - the directions of the pipes are perpendicular or at a different angle to each other;
• offset - the axes of the nozzles are offset relative to each other.

Based on the type of outer body, a distinction is made between cast, stamp-welded, litho-welded, and litho-stamp-welded products.

According to the method of attachment to the pipeline

In this category, the following types of fittings are distinguished: flanged, wafer, wafer. In addition, products are produced for welding, as well as coupling ones, equipped with connecting pipes with internal threads applied to them.

By seal type

Reinforcement products, the design of which includes a gland seal for sealing, are called stuffing boxes. If this type of seal is not used, then in this case they talk about sealless fittings. This category includes such varieties as membrane and bellows.

A detailed and detailed classification of pipeline fittings allows you not to get lost in the variety of models and choose exactly the type of device that best suits the tasks assigned to it.

Source: https://www.stroysmi.ru/kommunikatsii/truby-i-vodoprovod/truboprovodnaya-armatura-raznovidnosti-i-naznachenie/

The use of various types of shut-off and control valves in pipeline systems - Prof Pipes

Catalog of control valves ARMATEK

Control pipeline fittings are designed to regulate the parameters of the working environment by changing the flow rate or flow area.

It does not necessarily have to provide complete closure of the flow area, and it should not be used as a shut-off valve. It is equally undesirable, and sometimes unacceptable, to shift the “responsibilities” of control valves to shut-off valves.

To simultaneously perform the functions of shut-off and control valves, there is a combined type ─ shut-off and control valves.

In the currently valid GOST 24856-2014. Pipeline fittings. Terms and Definitions" it is not recommended to call control valves throttle or throttle-regulating, and shut-off and control valves - shut-off and throttle. And it is completely unacceptable to use such “terms” as “adjustable valves” and “shut-off and adjustable valves.”

What types of control valves are there?

Various types (or more correctly, varieties) of control valves are produced. Of the four main types of pipeline fittings, three are used in this capacity - valves, taps and butterfly valves.

Only control valves, which are primarily related to shut-off valves, are used to a limited extent. A number of regulatory documents specifically stipulate the undesirability of using shut-off valves as control valves.

But, as you know, there are no rules without exceptions.

Control valves can be implemented in the form of regulators.

Although it is incorrect to consider regulators as an independent type of control valve based on the design of the valve, since the type of valve is determined by the direction of movement of the locking or control element relative to the flow of the working medium. And regulators are devices in which one of the above types of fittings (for example, a valve) is just part of the structure.

The main “array” of control valves is formed by control valves, which are often the most significant and expensive element of the control loop.

Control valves can be designed to perform specific tasks. For example, the so-called

a breathing valve (other names ─ inlet valve, outlet valve) is used to seal containers containing gas, air or steam, ensuring that the specified pressure parameters are maintained in the spaces of these containers.

With the help of a pressure reducing valve, due to an increase in hydraulic resistance, the operating pressure in the system is reduced.

There is a wide variety of control valve designs. They can have one valve - a single-seat valve or a flow area formed by two or more valves located in series on the same axis - a multi-stage valve, for example, a double-seat control valve.

In the increasingly widespread cage valves, the valve is made in the form of a stationary part, which, due to the presence of profiled holes in it for the passage of the working medium, is called a cage. A plunger moving inside the cell changes the total open cross-sectional area of ​​these holes, which allows the cell valve to effectively perform regulatory functions.

The spool ─ the locking element of the valve shutter, which provides regulation of the flow of the working medium, ─ can be disc-shaped, piston (cylindrical), spherical, needle-shaped. In the latter case, the control valve is called a needle valve.

Ball valves are well suited for regulating viscous liquids and slurries. To control control valves, different drives are used: pneumatic, hydraulic, electric.

Main parameters of control valves

One of the main parameters of control valves is throughput, which is numerically equal to the flow rate of the working medium with a density of 1000 kg/m flowing through the valves at a pressure drop of 0.1 MPa (1 kgf/cm).

It served as the basis on which a whole family of parameters was formed, containing the phrase “throughput”: conditional throughput, initial throughput, minimum throughput, relative throughput, actual throughput.

An equally important parameter is the throughput characteristic - the dependence of the throughput on the stroke of the valve. Determined experimentally, it is called the “actual throughput characteristic”.

In addition to it, there is also a linear throughput characteristic, an equal percentage throughput characteristic, and a special throughput characteristic.

And also other characteristics: design characteristic (dependence of the flow area in the valve of the control valve on the current stroke), cavitation characteristic, operating flow characteristic.

A quantitative criterion for leakage in a control valve valve is a parameter called relative leakage. Of course, control valves must ensure tightness when closing, but the ability to regulate flow is more important.

Therefore, for control valves, indicators that reflect their ability to regulate the working environment, ─ control range, regulator setting range, control zone, are of particular importance.

When developing, constructing, manufacturing and subsequent use of control valves, parameters such as insensitivity, dead zone, cavitation coefficient and others are also taken into account.

The value of control pipeline fittings

Control valves have an important place in the general range of pipeline fittings. Marketing research conducted in Russia and abroad, based on analysis of the global and domestic markets, invariably records a high share of control valves in the total volume of other types of pipeline fittings.

Regulating the flow parameters of the working environment, necessary for the effective management and control of technological processes, is a technically very difficult task. Including because a change in the position of the regulatory body is often accompanied by a dynamic change in the parameters of the working environment - pressure and flow rate.

Without control valves it is impossible to ensure the stability of nominal modes and the “normal” occurrence of transient processes. Efficiently operating control valves are a guarantor of the normal functioning of pipeline transport, energy equipment and many other industries.

Thus, in thermal power engineering, its use helps to ensure effective control of the operation of boilers, their safe and economical operation in design modes. Control valves must be installed on the feed lines of each boiler. Pressure regulators are a mandatory attribute of heating points with variable steam flow.

The use of shut-off valves to regulate steam pressure is not permitted. In order to adequately respond to the challenges of the time, caused by the general complication of technology, increasing requirements for efficiency and environmental safety of industrial systems, control valves must be constantly improved.

The main priorities are increasing its reliability, reducing energy consumption, increasing control accuracy and speed, and increasing corrosion resistance.

And at the same time, the design of control valves cannot be overly complicated, since it must have an acceptable cost, remain convenient to use, and not require complex and expensive maintenance during the period between repairs.

Requirements for control pipeline fittings

Control valves are subject to a wide range of requirements that they must meet throughout their entire life cycle. In particular, these are requirements for the type of control characteristic and the accuracy of parameter control. For example, regulating the duration of closing and opening cycles, as well as fixing the shutter in the desired intermediate position.

The control valves must be strong and rigid, able to withstand high mechanical loads without plastic and elastic deformations.

Like any other pipeline fittings, control valves have no right not to be sealed. Both in relation to the external environment and to the sections of the pipeline separated by the valve.

Control valves must be reliable and durable, i.e., capable of reliably performing their functions for a given period. Guaranteed ─ means with an acceptable failure rate, with a given probability, performing a set number of operation cycles before the first failure.

Operation of control valves should be convenient and not be accompanied by significant operating costs. This means that maintenance of control valves does not require frequent and labor-intensive adjustments, lubrication, etc.

This is especially important for valves located in unattended rooms, installed in remote sections of pipelines or continuous cycle production facilities, the stopping of which for preventive maintenance is highly undesirable.

Shut-off and control valves

Technical devices have become widespread that are not limited to solving the problems facing control valves, but can also serve as shut-off valves, ensuring shut-off of the flow of the working medium with a certain tightness, which has given rise to a separate type of combined valves. Shut-off and control valves are pipeline fittings that combine the functions of control and shut-off valves.

It can be clearly illustrated by shut-off and control valves. For example, KZR valves, designed to regulate and shut off the flow of a controlled environment. They demonstrate how shut-off and control valves for heating systems can be successfully combined in one technical device.

Shut-off and control valves for heating, which make it possible to regulate the parameters of the coolant and, if necessary, temporarily turn off individual heating circuits, make centralized and autonomous heat supply systems more convenient, safe and energy efficient.

This is equally true for both “small” sanitary fittings and fittings used in “large” heat and power plants. Including in technological systems, including security systems, of such complex and critical objects as nuclear power plants of any type.

And also in supply ventilation systems, hot water supply, central and individual heating points (central heating points and ITP), when regulating a wide range of technological processes in a wide variety of technology areas.

Without using modern control valves, it is impossible to simultaneously ensure reliable and most economical operation of equipment in a variety of areas of modern technologies: in all sectors of the energy sector, including nuclear, which is at the forefront, pipeline transport, the chemical industry and others.

Source: https://profpipe.ru/kak-pravilno/ispolzovanie-razlichnyh-vidov-zaporno-reguliruyushhej-armatury-v-truboprovodnyh-sistemah.html