Odk ppu. Operational remote control of PPU pipelines - an effective means of control or a useless application

Today they are used for heating different materials. One of them is polyurethane foam. His popularity is on the rise. But like any material, it can be damaged. The UEC system for PPU pipes comes to the rescue. It controls the insulating layer of the pipeline. Thanks to the JEC, it is possible to prevent damage to the pipe by taking timely measures. This reduces repair time and costs.

UEC system: purpose, principle of operation, damage repair

What is ODK? This is an operational system remote control. Produces constant and continuous monitoring (PPU). Monitoring is carried out throughout the service life of the heating main.

The system is designed to detect such defects as:

• damage to the pipe itself;
• damage to the polyethylene wrapper that wraps the pipe and the thermal insulation layer;
• damage to signal wires;
• the process of closing the signal wires to the pipe;
• poor butt connection of wires.

The principle of operation of the UEC is based on a sensor that controls the insulation layer, namely its humidity, which runs along the entire length of the pipeline. At least two wires are located in the thermal insulation layer and connected along the entire length of the pipeline. At the start and end points, they are connected into one loop. The loop is copper signal wires. Between the steel pipes and the polyurethane foam layer of thermal insulation, a sensor is formed to control the moisture level of the thermal insulation.

Sensor tasks:

• control of the entire length of the sensor and control of the length of the signal loop. Identification of the length of the section of the pipeline that is covered by the sensor;
• moisture control of the thermal insulation layer;
• search for the place where the thermal insulation layer has been moistened or the signal wire has broken.

The task of the sensor is to provide accurate data on the moisture content of the thermal insulation. When the amount of moisture increases in the thermal insulation layer, it means that it can be either a coolant leak from the pipe or moisture from the outside. As soon as this happens, the sensor reports by reflecting the pulse.

The principle of recognition of the damage site and its elimination:

1. as soon as the thermal insulation is broken, the sensor reports this. It remains to find damage in the area that is between the signal indicators;
2. the allocated area is disconnected from UEC systems;
3. overlaying data on the joint scheme;
4. based on the data obtained, it is dug out desired area pipeline and repairs.

PPU pipes - a new and promising development

The question remains, what is PPU? Everything is pretty simple. These are polyurethane foams - a universal group of polymers. The material is new, but already gained its popularity.

The Russian climate forces us to heat our homes. And the acute question is not how to bring heat into the house, but how to bring it with the least loss. Previously, the pipeline was wrapped with glass wool, fixed with steel wire, and covered with galvanized steel sheets on top. The material is valuable, so it did not stay long on the pipes. Today, more and more pipes are made of polyurethane foam. It is also used for thermal insulation.

Advantages of PPU:

Stages of installation of PPU pipes:

1. sweep;
2. welding and quality control;
3. for this purpose, a flaw detector is needed;
4. putting on the clutch. Under it is poured polyurethane foam. The sleeve heats up and shrinks. This allows you to get the tightness of the connection.

The UEC system for a heating main is additional way protection. And it consists in preventing large emergencies and repair minor damage as quickly as possible.

The UEC system: what does it consist of

Built-in copper wire. It is the conductor through which the damage signal is transmitted. It is located in a heat-insulating layer of polyurethane foam. Without it, the UEC system will not work.

There are two types of wire:

• basic. It repeats the contour of the pipeline and is stretched along the entire path of the heating main;
• transit. Designed to form a signal loop and runs along the shortest path between the start and end points of the heat pipe.

Devices for control and measurements:

• damage detectors. They monitor the breakage or short circuit of the built-in signal wire. They do not establish the cause of the damage, but state the fact. The stationary detector (220 V) provides constant control, the portable one (9 V) provides periodic control. The first option can control from one to four pipelines. Has an alarm system. The second option works autonomously, powered by a battery. Able to serve an unlimited number of pipelines. They are installed at control points using a switching terminal;
• pulse reflectometer. Able not only to fix the damage, but also to find its location. Does not provide information about the causes of the defect. Connected at the factory and before installation to the ends of the pipes in those places where the signal wires come out of the insulation. It is also connected during control, directly during the operation of the heating main.

The switching terminal of the UEC system is presented as an intermediate link between the control devices and the pipe. Usually they are placed from each other at a distance of 300 meters. They are used to connect control devices, as well as switching signal wires.

The project of the UEC system - how it happens

The UEC system for PPU pipes is designed with the ability to connect with existing existing heating mains, as well as with only planned pipelines.

One of the two signal wires is marked (it is also the main one). It is located on the right in the direction of water movement to the destination. The location of the conductor from the surface of the pipe ranges from 10 cm to 25 cm.

The resistance indicator must meet certain requirements:

• for signal wires per meter of length, the resistance should range from 0.012 ohms to 0.015 ohms;
• for PPU insulation for 300 meters of pipe length - 1 Ohm.

For various conditions operation, various switching terminals are used. The classification depends on various conditions.

Weather:

• measuring instruments are used only in dry and ventilated conditions;
• sealed. Apply under the condition high humidity air.

Territorial:

• terminal, used at the end points of control;
• unifying. It is used at the junction points of some sections of the heating main;
• combining with the possibility of access to stationary detectors;
• checkpoint. In those places where a rupture of the insulating layer was recorded;
• intermediate. It is installed at control points where the side branch of the heating main begins, as well as at intermediate control points.

The maximum length of the heating main for the UEC project is calculated by determining the maximum scope of control devices.

The above-mentioned sensors are selected depending on the availability of 220 V in the projected area where the use of UEC systems is planned:

• if 220V is present, a fixed detector is used.
• in the absence of the necessary resistance, a portable one is used.

What devices will be installed and their number depends on the length of the heating main section. If the length of the planned heating main is longer than that allowed for the operation of the detector, this section of the heating main is divided into smaller sections. For them are used individual systems control.

The control points provided by the project are intended for the possibility of access of the operating personnel to the signal conductors. The points should not be further than 300 meters from each other.

The terminals are installed in the carpet at the end points. Also, their installation is possible in central heating points.

The ODK system (operational remote control) is used to detect mechanical or chemical (caused by corrosion) damage to isothermal pipelines laid by air or underground. To date, it has become widespread, being used as part of the pipelines of the most for various purposes(including utilities).

To important features UEC systems should include:

• high level of automation of the damage search process;
• its continuity;
• accuracy of detection of damage sites;
• reliability and security of the system against failures under any operating conditions;
• relatively low cost of system components;
• ease of use.

The purpose of using the ODK system is:

• detection of places of depressurization of the serviced pipeline;
• detection of places of depressurization of its outer shell.

In addition, the UEC system is able to detect its own malfunctions, including

• violation of the integrity of conductors-detectors;
• poor butt connection of detector conductors;
• closing conductors-detectors on the pipe.

UEC system: principle of operation

The principle of operation of the UEC system is based on the fundamentals of pulsed reflectometry technology. In accordance with it, the conductor-indicator acts as a pulsed emitter, the pipe and the outer shell act as reflectors, and the heat-insulating layer acts as a medium with certain wave properties. It is on the constancy of these properties that the operation of the mechanism is built.

If the thermal insulation layer gets wet, it wave properties change in the direction of decreasing resistance and, as a result, increasing conductivity. This is immediately detected by special control and measuring instruments that combine the functions of a reflectometer and a megohmmeter.

An increase in the humidity of the heat-insulating layer, mounted in accordance with all the rules of an insulated pipeline, can be caused either by damage to the pipe and leakage of the medium transmitted through it, or damage to the outer shell and moisture ingress atmospheric air(as an option - soil). Either way, repairs are needed.

Modern UEC systems have several stages of operation. This makes it possible not only to detect the very fact of depressurization and establish its location, but also to determine the extent of possible damage. The detection accuracy is very high, and the error probability is zero.

UEC system: equipment composition

The standard OEC system has three technological levels

• conductor-detectors made of copper wire (wire section diameter 1.5 mm) with output cables;
• switching terminals for connecting control and measuring devices installed in carpets (special safe-type metal boxes, which are available in wall and ground versions);
• stationary or mobile control measuring instruments, also referred to as "damage locators".

The structure of the UEC system is universal. This makes it easy to expand and rebuild it, providing the most complete and most effective monitoring possible. technical condition pipeline communications.

The procedure for using the ODK system is extremely simple. It includes the following technical steps:

• checking the readiness of the control and measuring device and the integrity of the conductor network (self-control);
• data removal;
• saving data for further analysis.

The frequency of control measures using the UEC system is not regulated by law and is established by operating organizations on an individual basis.

The LLC PO SanTermo company produces heat-shrinkable couplings of all required sizes. This product fully complies with the requirements of GOST 16338, is certified, and undergoes a thorough quality control before shipment from the factory. Many enterprises of thermal power engineering and public utilities prefer to use heat-shrinkable sleeves of our production, as they consider them to be optimal in terms of price-quality ratio. Fast and high-quality sealing of joints between PPU pipes laid in a trench is important for maintaining high rates of construction of heating mains and ensuring long term their trouble-free operation. Thermal couplings from the SanTermo company are made of dense and durable polyethylene, and if the installation rules are followed, the tightness of all closed joints is guaranteed!

The production of pipes in polyurethane foam insulation is one of the main and priority activities of the SanTermo company. Pipes insulated with polyurethane foam allow to minimize the loss of thermal energy and prevent leakage of liquids transported through pipelines, they are protected from corrosion, they serve for a long time and reliably. We have created our own highly efficient production, and for more than 5 years we have been supplying pipes and shaped products in polyurethane foam insulation construction companies, utility companies and wholesale supply organizations in all regions of Russia. The production processes at the PO SanTermo LLC plant are constantly being improved to provide even more high quality all types of pipes and fittings in polyurethane foam insulation, and minimize their costs. This will allow us to offer our numerous partners even more low prices. All products are certified, undergo a thorough technical control quality.

The SanTermo company manufactures and sells bellows compensating units of various modifications and standard sizes, including specially designed for heating networks compensators SKU PPU in polyurethane foam insulation and a protective sheath made of polyethylene or sheet steel. PPU as a type of industrial insulation is most widely used in the manufacture of pipes for the construction of modern heating networks. The use of one or another material for the outer containment depends on the method of laying the pipeline.

Advantages of using the operational remote control system (SODK)

Hardware controls for the integrity of the outer layers of waterproofing are used on pipelines built from pipes insulated with polyurethane foam (PPU). The need for such control arose due to the ability of PPU insulation to absorb water. The moistened porous insulator not only has a high coefficient of thermal conductivity and practically does not fulfill its main function, but also causes moisture to enter the surface of the working pipe and corrode it. Water can enter the thickness of the PPU insulation only through cracks in the polyethylene outer shell of the PPU pipes. Systems SODK make it possible to timely detect sections of heating mains that need to be replaced with wet insulation and restoration of the tightness of the containment.

Purpose

Operational dispatch control systems ( SODK) are created for the purpose of continuous monitoring of the state of porous polyurethane foam pipe insulation, and exact definition places of violation of external waterproofing, requiring immediate repair.

Principle of operation and organization of the system

The fact of wetting the insulation in one or more sections of the pipeline complex of technical means SODK registers by changing its resulting electrical resistance. To enable such measurements, at the stage of manufacturing PPU pipes, copper conductors are laid along the entire length between their outer shell and the surface of the steel pipe on special insulators. SODK. After filling the cavity between the shell and the working pipe with polyurethane foam, the conductors are inside the thermal insulation layer.

During the installation of pipelines, conductors SODK are connected in series into a circuit, which is subsequently connected to the equipment of the dispatch center SODK. To ensure the possibility of measuring the insulation resistance in individual sections of pipelines, during their installation, pipes equipped with control leads connected to the main conductors are installed at a certain interval. SODK. Insulated control wires are brought to the surface and connected to specially equipped switching terminals.

The composition of the equipment and the scheme of the control system

The whole range of equipment used SODK can be divided into several main groups:

• Technical means of stationary control rooms.
• Groups of portable (wearable) measuring instruments SODK- testers, detectors and various design locators of damage to waterproofing pipes.
• Switching terminals installed at the ends and along the route, allowing connection of measuring instruments.
• Families of protective boxes (carpets SODK) to safely accommodate outdoor equipment.
• Groups of tools and all necessary Supplies used in the installation of supervisory control systems SODK.

Wiring diagram of the control system SODK make up the signal conductors of the pipe part, the measuring equipment of the stationary control room, as well as the entire system of end, through and intermediate switching terminals that provide the ability to quickly connect control equipment.

Additional devices

To the group of additional devices used in the construction and operation of control systems SODK, include various types of mounting and adapter cables - connectors. These accessories are used to connect the mounted terminals SODK co stationary devices control, as well as for connection to intermediate terminals various kinds control and measuring equipment.

Types of faults recorded by the control system on pipelines with polyurethane foam insulation

The main parameter that controls the stationary equipment of the control room is the electrical resistance of the PPU pipe insulation between the extended conductor SODK and the surface of the steel pipeline. With a critical decrease in the value of the measured resistance, it can be judged that the insulation is moistened due to a violation of the external waterproofing. If the resistance of a section of pipe insulation drops to almost zero, a shorted signal wire may be the likely cause. SODK with "earth". An increase in the controlled parameter to infinity can be recorded only when the electrical circuit is broken SODK.

Damage detectors

In the event that the control equipment of the central control room SODK will issue a message about a sharp decrease in the electrical resistance of the transition "conductor - steel pipe”, a team equipped with special measuring devices leaves for the track in search of a place for a breakdown of waterproofing. These include various models of portable detectors that allow you to control the resistance of pipe insulation in a section of 2-5 kilometers, as well as portable impulse reflectometers. These devices are periodically sent to conductors SODK a high-frequency pulse, after which, using the parameters of the reflected signal, they are able to calculate and indicate with maximum accuracy the distance to the place of leakage of the damaged containment.

Design rules for SODK

System Design Order SODK determined by current standards. Prepared project of the complex SODK includes explanatory note, wiring diagram pipeline and the control system diagram attached to it, as well as a complete specification of the necessary equipment, components and materials. When developing a project, it is necessary to balance the frequency of installation of control terminals with the maximum range of measurements using detectors (no more than 5 km).

Diagram of the control system

The scheme of the complex attached to the project SODK includes a graphic electrical circuit switching conductors of the pipe part with the equipment of the dispatching post and control points of linear and terminal switching terminals.

Thermally insulated expansion joints SKU.PPU are one of the most demanded models of bellows-type compensating devices on the market. Their area practical application covers the areas of pipeline construction by means of channelless underground and open ground laying. Guaranteed high build quality, excellent performance characteristics and the low price level of SKU.PPU compensators produced by the SanTermo Production Association provided this type of product with a stable demand for companies specializing in the construction of thermal power pipelines.

The LLC PO SanTermo company produces heat-shrinkable couplings of all required sizes. These products fully comply with the requirements of GOST 16338, are certified, and undergo thorough quality control before shipment from the factory. Many enterprises of thermal power engineering and public utilities prefer to use heat-shrinkable sleeves of our production, as they consider them to be optimal in terms of price-quality ratio. Fast and high-quality sealing of joints between PPU pipes laid in a trench is important for maintaining high rates of construction of heating mains and ensuring a long period of their trouble-free operation. Thermal couplings from the SanTermo company are made of dense and durable polyethylene, and if the installation rules are followed, the tightness of all closed joints is guaranteed!

The production of pipes in polyurethane foam insulation is one of the main and priority activities of the SanTermo company. Pipes insulated with polyurethane foam allow to minimize the loss of thermal energy and prevent leakage of liquids transported through pipelines, they are protected from corrosion, they serve for a long time and reliably. We have created our own highly efficient production, and for more than 5 years we have been supplying pipes and fittings in polyurethane foam insulation to construction companies, utilities and wholesale supply organizations in all regions of Russia. The production processes at the plant of OOO PO SanTermo are constantly being improved to ensure even higher quality of all types of pipes and fittings in polyurethane foam insulation, and to minimize their costs. This will allow us to offer even lower prices to numerous partners. All production is certified, passes careful technical quality control.

Tape "TIAL"

One of the most famous and well-established in practical work material for corrosion protection and waterproofing of pipes is a thermoshrinkable tape "TIAL". LLC PO SanTermo sells almost the entire available range of heat-shrinkable materials from a popular Russian manufacturer of products for sealing joints and protecting pipes from corrosion. The TIAL-M tape consists of two layers, the lower of which, due to its high adhesive properties and thermoplasticity, ensures perfect adhesion to the surface to be protected. Secondly, the outer layer of modified heat-shrinkable polyethylene is extremely durable and resistant to ultraviolet radiation. This tape is used for additional sealing and protection of the installation site of heat-shrinkable sleeves at the welded joint of the pipeline. In addition to the TIAL-M tape, you can purchase from us lock plates TIAL-3P and adhesive tape TIAL-3. These materials are also used to provide a better tightness at the pipe connection.

PPU insulation for pipes is the most common and effective material, the use of which can significantly reduce losses in the thermal power industry, significantly reduce construction costs and minimize the operating costs of new heating networks built from PPU pipes. SanTermo specializes in the production of pipes and fittings in polyurethane foam insulation, and can offer customers all the necessary sizes of these products. As a material to protect the insulation layer from damage and excessive moisture, polyethylene (PE) and galvanized sheet steel (OC) are used. Modern production insulated pipes, created by us, allows us to produce products of the highest quality, competitive in the Russian market both in terms of technical and physical parameters and in price. Our regular customers and partners enjoy maximum discounts and have the right to extraordinary shipment. We accept applications from pipe manufacturers and wholesale supply companies for manufacturing finished products in polyurethane foam insulation from the customer's pipes.

The subject of special pride of the staff of the company LLC PO SanTermo is a plant for the production of pipes in polyurethane foam insulation. A modern high-tech enterprise, staffed by well-trained personnel and equipped with everything necessary technological equipment, capable of solving production and engineering problems of any complexity. The geography of deliveries of insulated pipes manufactured by the SanTermo PO plant covers not only the nearest industrial centers, but also many fairly remote cities. The unique thermal and strength characteristics of PU foam insulation are the main factor rapid growth the number of projects that are carried out using PPU pipes. Among our regular customers are construction organizations, utilities and large wholesale companies. Pipes in polyurethane foam insulation have become a sought-after product, and our team is pleased to offer its customers high-quality products at the best price.

Steel pipes in polyurethane foam insulation have numerous advantages. Most of of them is due unique properties the main insulator is a gas-filled polyurethane foam polymer. This material seems to have been specially created for the production of thermal insulation of steel pipes. It holds up very well metal surface, strong enough, can endure temperatures of +135°C for a long time without loss of strength, and for a short time even 150°C. But its main advantage is a very low coefficient of thermal conductivity. In the volume of PPU components frozen after a chemical reaction, there is no more than 10% -15% solid. The rest is air bubbles, which are the reason for such poor heat conduction. In addition, the very method of applying a layer of PPU insulation on steel pipes is very convenient. It is enough to place the prepared pipe inside the future containment, seal the ends with special plugs, and introduce two liquid reagents into the resulting cavity. After the end of the chemical reaction, the steel pipe will be separated from the shell by a strong layer of polyurethane foam.

When installing heating mains and pipelines from pre-insulated PPU pipes, in places of turning, bending, or connecting additional branches to the main pipeline, it is necessary to install fittings in PPU insulation. It is necessary to use insulated bends, tees and other components in order to ensure the same temperature regime all sections of the pipeline, and the possibility of excessive leakage of thermal energy is completely excluded. All shaped products in polyurethane foam insulation, produced by the plant of the company PO LLC "SanTermo", are distinguished by high quality and reliability. Thermal insulation made of polyurethane foam is reliably protected by an additional shell, which, depending on the needs of the customer, can be made of solid polyethylene or high-quality galvanized steel. The company sells to buyers and customers shaped products in polyurethane foam insulation according to the most affordable prices, as it is a direct manufacturer of these products, and is constantly working to reduce production costs.

Since 2009, PO LLC SanTermo has been producing steel pipes in polyurethane foam insulation. During this time, a powerful production base has been created at the enterprise and a team of like-minded professionals has been formed. Today, the company's pre-insulated pipe plant produces everything necessary for laying new pipes, as well as repairing and modernizing existing pipe lines. Steel pipes in polyurethane foam insulation from the company "SanTermo" - a guarantee of standard quality and long service life of the built ones. The company manufactures and sells a full line of products that are necessary for the construction of resource-saving pipelines - steel pipes in polyurethane foam insulation of all required sizes, insulated fittings, polyurethane foam shells and sets of materials for quick insulation of joints. Steel pipes in PPU insulation are offered to all buyers and customers at the lowest, competitive prices that only a manufacturing company can provide. Regular customers and wholesale partners receive additional discounts.

Operational remote control system SODK

Product groups

SODK system

SODK- a set of technical means designed for operational control of the integrity of the protective shell of pipes in PPU insulation, and quick repair work in case of damage. The violation of the tightness of the shell is judged by the change in the dielectric resistance of the polyurethane foam insulation of the pipeline. When it is locally wetted, the resistance value changes between metal pipe and a copper conductor laid inside the insulation layer SODK.

Purpose, principle of operation and technical implementation of SODK

Ability to create electronic system SODK, which controls the state of the thermal insulation layer of PPU pipes and the tightness of their outer shell, favorably distinguishes this species pre-insulated pipes and greatly increases the reliability of industrial pipelines built from them. Designed to continuously monitor the moisture content of the entire volume of PU foam insulation, the system SODK allows you to guaranteedly avoid accidents associated with the penetration of water to the surface of working steel pipes, and - as a result, damage to them by corrosion.

In addition, in the event of a violation of the tightness of the outer shell and wetting of polyurethane foam, its thermal conductivity increases sharply, which significantly worsens thermal insulation properties this section of the pipeline. Timely detection of defects in pipe insulation using the hardware complex of the system SODK allows you to quickly produce necessary repairs damaged area, to prevent uncontrolled development of the situation and the significant material damage associated with it.

Operating principle

Operation of hardware control complexes SODK based on the principle of measuring the resistance of the thermal insulation layer electric current. Being a dielectric under normal conditions, wet polyurethane foam becomes a conductor - its resistance drops to 1.0-5.0 kOhm, which can be recorded by appropriate devices SODK. To ensure the possibility of making such measurements simultaneously along the entire length of the pipeline, PPU pipes are equipped with special conductors integrated into the polyurethane foam layer at the stage of manufacturing thermal insulation.

Later, during the construction of pipelines, the conductors of all installed pipes are connected into a single circuit. By measuring the electrical resistance of the transition "steel pipe - signal wire SODK, the system equipment is able to register any, even the most insignificant, deviation of the real parameters from the reference values ​​entered in the technical passport of the pipeline at the time of the start-up tests. If a SODK registered the presence of insulation wetting, with the help of special remote-action devices - pulse reflectometers, the location of the defect is determined with a high degree of accuracy and repairs are promptly carried out.

The composition of the UEC equipment

The whole complex of technical means SODK It is customary to conditionally divide into three groups - the pipe part, signaling equipment and a group of additional devices. The pipe part includes all passive electrical elements- from conductors mounted in pipes and connecting mounting accessories, to intermediate and end cable outlets. To signal group SODK include the active part of the equipment - measuring instruments, matching devices and switching facilities.

A group of additional devices is formed by securely closing ground and wall metal constructions- carpets, in which the equipment of the signal group is installed during the installation of the system. Thus, the composition of the equipment SODK includes:

1.Pipe part- conductors mounted in pipes, all mounting and connecting accessories and cable outlets.
2.Signal group- active equipment SODK:
2-1. Control devices: stationary and portable damage detectors.
2-2.Instrumental means of localizing the defect - pulsed reflectometers.
2-3. Equipment installed in control rooms.
2-4. Auxiliary devices - insulation testers, ohmmeters and megohmmeters.
2-5. Switching measuring terminals. There are end, double end and intermediate terminal boxes.
2-6. Sealed terminals - securely closed wiring boxes that protect connections and connected devices from moisture. Distinguish end, uniting and through tight terminals.
3. Additional devices- ground and wall metal carpets.

One of the most costly components of equipment SODK are control devices and technical means troubleshooting. Monitoring devices include stationary and portable detectors, each of which is capable of monitoring sections of pipelines from 2000 to 5000 meters long. Domestic manufacturers produce a line of high-quality devices that allow you to completely abandon the purchase of imported equipment - Vector-2000, SD-M2 (NPP Vector), PIKCON DPS-2A / 2AM / 4A, DPP-A / AM (LLC "Termoline"). In the group of devices for finding damage, equipment is also widely represented. Russian production- REYS-105/205 (NPP Stell) and RI-10M/20M (ZAO Oersted).

Design rules for control systems

Systems Design SODK is carried out on the basis of the provisions of GOST 30732-2006 and the Code of Rules 41-105-2002. The design organization develops and transfers to the customer a set of documents, including the rationale for the structure and composition SODK, a master plan indicating the places where cable outlets are provided, installation of carpets and switching terminals, diagrams of electrical connections and wiring in the terminals. A separate document contains a list of measuring equipment, control devices and devices for finding faults, recommendations for the production installation work and subsequent maintenance systems SODK.

At the design stage, it is important to determine the most optimal distances between cable outlets and indicate exactly where the carpets are to be installed. It is recommended to have intermediate control points and corresponding terminals SODK at a distance of no more than 300 meters from each other. At each end of the route, it is necessary to provide for the installation of end cable outlets and terminals designed to connect stationary and portable detectors. All equipment must be located in such a way as to facilitate operation. SODK and ensure maximum accuracy in the production of control and diagnostic measurements.

To the installation of pipe conductor connections, cable outlets and preparation for the placement of ground and wall terminals SODK start immediately after the welding work is completed and hydraulic tests. The procedure for performing installation work, control measurements and transfer of the finished operational dispatch complex to operation should be described in detail in the project. Connection of conductors SODK neighboring pipes is made during the insulating sealing of joints. These and any others electric installation work complete by performing control measurements and assessing the quality of each field connection.

One of the stages of transferring the mounted system SODK to the customer involves the measurement of the resulting ohmic resistance of the mounted signal conductor and the insulation resistance of the "signal wire - working pipe" section. Measurement results are recorded in special magazine and during subsequent operation SODK are used for this pipeline as reference values.

Types of malfunctions and search for places of damage

During operation, the system SODK controls one the most important parameter the state of the pipeline - the absence or presence of moisture in the thermal insulation layer, and its own state - the serviceability of the signal wire. Accordingly, based on the measurement results, the system can fix any of the following faults:

• Wetting of a separate section of thermal insulation.
• Short circuit when the signal conductor contacts the surface of the working tube.
• Damage (break) of the signal conductor.

The search and localization of the defect site is carried out using portable and stationary detectors, and the most accurate and effective instrument- pulse reflectometer. Detectors help to determine the area between control points where a malfunction is detected. This section of the circuit is temporarily turned off, and by sending a control high-frequency pulse through the wires, data is obtained on the time of passage of the reflected signal. By comparing the data obtained from each side of the control section, the distance to the accident site is calculated.

SODK system for pipeline control