Project operational system remote control SODK.

In this project, a system was designed for systematic monitoring of the insulation condition and prompt identification of areas with high insulation moisture in pipelines made of polyurethane foam pipes.

The operating principle of a pulse-type SODC is based on measuring the electrical resistance of the heat-insulating layer between a steel pipe and two copper wires of the control system, forming a signal circuit that runs along the entire length of the pipeline.

Basic requirements for the elements of the SDS system:

1. The distance from the copper wire to the steel pipe is 15 mm.

2. Insulation resistance monitoring:

The resistance between the signal wire and the steel pipe (for one pipe or fitting - 20 m of wires or less) must be at least 10 MOhm;

The insulation resistance of 300 m of pipeline varies inversely;

To monitor the insulation resistance, a voltage of 500 V should be used.

3. Signal loop resistance control:

Resistivity copper wires 0.012-0.015 Ohm/m;

Exceeding the permissible value of the signal circuit resistance for the corresponding length of the control system wires indicates a poor-quality connection of the wires at the joints.

In the production of pre-insulated pipes and fittings, copper wires of the control system are installed in them as standard. Tinned metal is used as the main “signal” copper wire white, which is located in the pipeline on the right in the direction of water movement (for return pipeline direction as for the server). The second wire - bare copper - "transit" runs throughout the heating network without breaks.

For systematic monitoring of the insulation condition, it is possible to use a portable damage detector "Vector 2000" and the ability to connect it to the measuring terminal "KT-11", as well as a locator - a pulse reflectometer "Reis-105R" to determine the exact location of the damage and the type of defect (wet insulation, break of the signal wire) when connecting it to the terminals "KT-11", "KT-12" and "KT-13".

Organization of control using the SODK system:

Control electrical parameters The signal circuit is carried out separately through the supply and return pipelines.

Looping of wires is provided in the end element of the UEC system.

On pipelines with polyurethane foam insulation, two-stage monitoring of moisture and insulation condition must be carried out:

At the first level, constant monitoring of pipelines is required to determine the condition of the insulation - this is carried out by operating personnel using a damage detector, which allows determining the presence of damage; to determine the location of the detected damage, a second level of monitoring is needed;

At the second level of control, control should be carried out using a pulse reflectometer (damage locator) and only by highly qualified, specially trained personnel.

To organize such monitoring of the state of polyurethane foam insulation, it is necessary:

1. Organize periodic monitoring using a portable damage detector: 2-4 times a month.

2. Organize a complete in-depth periodic examination using a pulse reflectometer: once a quarter. The survey data is entered into the database in order to monitor the dynamics of the state of the PU insulation.

3. Organize immediate determination of the location of the damage after the detector is triggered and its elimination.

Installation of the SODK system:

The project was carried out in accordance with the "Instructions for the design, installation and operation of a pulse-type operational remote control system (ORC").

Installation of pipeline joints and installation of the UEC system is carried out by the supplier of PI pipes - ZAO Polymer Pipe Plant, Mogilev.

The control system wires are connected at the joints of the elements and are led out through sealed cable terminals into the switching terminals.

Connecting cables from cable terminals to the carpet (three-core NYM3x1.5 and five-core NYM 5x1.5) are laid in protective galvanized steel pipes

d = 50 mm. Welding (soldering) of a pipe with a cable laid in it is prohibited.

Cable connections are made in strict accordance with color coded lived, as well as in accordance with the passport attached to each terminal. The cable from the supply pipeline must be additionally marked (with insulating tape) both at the base of the cable outlet and at the entrance to the terminal.

Installation of carpets, placement of terminals and connections connecting cables is carried out in accordance with the schemes given in the project.

In this project, the length of the heating network route is 229.5 running meters.

To switch signal conductors and connect control devices, the following types of terminals are used:

End terminal "KT-11" - designed for switching conductors of the UEC pipeline system with polyurethane foam insulation at control points; connecting a pulse reflectometer to the UEC system. The terminal is installed in a wall box of the carpet near the entrance of the heating main to the educational building No. 3 of BelSUT;

Intermediate terminal "KT-12" - designed for switching conductors of the UEC pipeline system with polyurethane foam insulation at intermediate points; connection to the SODK pulse reflectometer. The terminal is installed in the existing ground carpet box in the courtyard of educational buildings No. 3 and No. 4;

End terminal "KT-13" - designed for looping conductors of the UEC system of pipelines with polyurethane foam insulation at the end points of the UEC system; connecting a pulse reflectometer (locator) to the UEC system. The terminal is installed in a carpet wall box in the basement of educational building No. 1.

The reasons for excess humidity may be the following:

• The outer protective layer allows moisture to pass through;
• Coolant leakage in places where the steel part of the pipeline is destroyed due to corrosion processes or defects in welded joints.

Using the operational remote control system (ORS)

In accordance with paragraph 4.24 of GOST 30732-2006 insulated pipes and products must be equipped with SODK conductors. Consequently, the installation of SODK is mandatory on pipelines, both with an external galvanized steel shell and with protective layer made of polyethylene.

Usually, in agreement with the customer, in the case overhead laying routes, the UEC system may not be installed, since areas with high humidity can be detected visually, without the help of detectors. Also, by agreement with the customer, the UEC system is not installed when underground installation heating mains, if for one reason or another the presence of a UEC system is not reflected in the project.

Composition of SODK

Typically, the UEC system consists of the following elements:

• Copper conductors;
• End and intermediate elements of the pipeline with output cable;
• Connection cable;
• Switching terminal for connecting fault detection devices;
• Damage detector;
• Pulse reflectometer.

Copper conductors SODK

In accordance with paragraph 5.1.9 of GOST 30732-2006, two conductors of the UEC system are located under the cover layer of thermal insulation of pipes with a diameter of up to 426 mm. The conductors consist of low-alloy soft copper grade MM with a cross-section of 1.5 mm2. The conductors are located parallel to the pipe axis in the plane of one section at a distance of (20 ± 2) mm from the steel pipe.

Centering supports attached to the steel pipe are used as conductor fixation points. The distance between the centering supports should be from 0.8 to 1.2 m. If the longitudinal seam of the steel pipe is in top point, the cable layout should correspond to the clockwise positions of “3” and “9 o’clock”. When using a pipe with a diameter of ≥ 530 mm, 3 conductors are used, fixed in the “3”, “9”, “12 o’clock” positions.

The main signal conductor is located with right side, in the direction of coolant supply to the consumer, in accordance with clause 4.59 of SP 41-105-2002. The second signal wire is transit. The difference between a signal conductor and a transit conductor is that the signal conductor enters all branches of the heating main, repeating its entire contour, and the transit conductor follows the shortest path between the starting and ending points.

Damage detector

The damage detector is designed to monitor the condition of the pipeline throughout the entire measured section. The device will be able to detect the following faults and deficiencies:

• Rupture of signal conductors;
• Short circuit of the signal conductor to a steel pipe;
• Wetting of the insulating layer.

The detector does not determine the exact location of the defect, nor the cause.

The operating principle of the detector is as follows. Polyurethane foam is characterized by high electrical resistance. The resistance of the insulating layer of polyurethane foam when exposed to moisture is significantly reduced. Electrical resistance measured between the conductors of the UEC system and the steel pipe. If the resistance value is below the threshold, the detector generates a “wet” signal. This signal can also be triggered when the signal wire touches a metal pipe.

The detector also measures the resistance of copper conductors. In case the resistance electrical circuit exceeds the limit parameter, the detector issues a “break” signal. Damage detectors are either stationary or portable.

Pulse reflectometer (Locator)

A pulse reflectometer (locator) is a portable device and is designed to search for defect locations. The device detects the same types of problems as a damage detector. The operating principle of the reflectometer is based on location measurement. Due to the correct installation of the indicator conductors relative to the steel pipe, when high-frequency electrical pulses are applied to them, and due to the electrical properties of polyurethane foam, wave resistance is formed, which is constant throughout the entire length of the pipe. Location by electrical impulses of low energy occurs unhindered.

Wetness of the insulating layer leads to a change in the value of the wave resistance, and, consequently, makes it difficult for the passage of pulses. The locator records pulses reflected from wet insulation. A pulse reflectometer allows you to determine the distance to the defect.

In addition to getting wet, changes in wave resistance can be influenced by:

• Changing the cross-section of the insulating layer;
• Coupling connection points;
• Places where conductors are broken;
• The end point of the signal line.

Control and installation tester

The tester is designed to measure polyurethane foam insulation and loop resistance of signal wires. Using a tester, it is possible to identify the same defects as using a detector.

The tester is usually used to test products with the UEC system directly during their production, installation, and operation of utility networks.

Switching terminal

In accordance with clause 4.69 of SP 41-105-2002, the following types of terminals must be used to connect signal conductors and connect monitoring devices:

• At the final control point of the pipeline - the end terminal;
• At the final control point of the pipeline, which has access to a stationary detector - End terminal with access to a stationary detector;
• At the intermediate control point of the pipeline - an intermediate terminal;
• At the control point at the border of the site there is a double end terminal;
• At the confluence of several sections of the pipeline there is a unifying terminal;
• At points where there is no insulating layer, a pass-through terminal is used to connect the connecting wire. Limit on maximum length wire is 10 m.

End terminals are mounted at the final control points of the heating network, intermediate terminals (one of them can be connected to a stationary detector) - on straight sections. Control points must be provided at a distance of no more than 300 m from each other. If the pipeline has a length of up to 100 m, it is equipped with 1 end terminal. In this case, it is possible to loop the SODC cables at the opposite point of the pipeline. The starting points of side branches with a length of about 30-40 m must be equipped with intermediate terminals without taking into account the location of other control points of the main pipeline.

Installation of SODK at joints

List of materials for mounting the operational remote control system:

• Tape for fastening (fastening to a steel pipe of ODK holders);
• Tinned copper sleeves - crimp sleeves with surface galvanic tinning for connecting conductors of the UEC system. The connection can be made “butt” and “overlapping”;
• UEC holders.

Technical specifications

In accordance with paragraph 5.1.10 of GOST 30732-2006, the resistance between the steel pipe and the conductors of the UEC system must be at least 100 MOhm with a test voltage of at least 500 V.

In accordance with paragraph 3.9 of SP 41-105-2002, the resistance of copper indicator conductors must be in the range of 0.012-0.015 Ohm/m. Insulation resistance 3.3 kOhm/m.

In accordance with clause 4.57 of SP 41-105-2002, the threshold resistance of copper indicator conductors must be 200 Ohms with a maximum length of 5000 m. If this parameter is exceeded, the detector generates a “Break” signal. The threshold insulation resistance should correspond to 1-5 kOhm. If the insulation resistance parameter is lower, the detector gives a “wet” signal.

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

UEC system: purpose, operating principle, damage correction

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

The system is designed to detect defects such as:

• damage to the pipe itself;
• damage to the polyethylene wrapping that wraps the pipe and the thermal insulation layer;
• damage to signal wires;
• the process of connecting signal wires to a 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 a layer of thermal insulation and connected along the entire length of the pipeline. At the starting and ending points they are connected into one loop. The loop consists of signal wires made of copper. Between steel pipes and a polyurethane foam layer of thermal insulation, a sensor is formed to control the level of humidity 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 pipeline section that is covered by the sensor;
• moisture control of the thermal insulation layer;
• searching for the place where the thermal insulation layer has become wet or the signal wire has broken.

The sensor's job is to provide accurate data on the moisture status of the insulation. When the amount of moisture in the thermal insulation layer increases, this means that it can be either a coolant leak from the pipe or moisture from outside. Once this happens, the sensor reports by reflecting a pulse.

The principle of recognizing the damaged area and eliminating it:

1. As soon as the thermal insulation is broken, the sensor reports this. It remains to find the damage in the area that is located between the signal indicators;
2. the selected area is disconnected from the UEC system;
3. overlaying data on the joint diagram;
4. based on the data received, it is dug up required area pipeline and repairs are being made.

PPU pipes - a new and promising development

The question remains, what is PPU? It's quite simple. These are polyurethane foams - a universal group of polymers. The material is new, but has already gained its popularity.

The Russian climate forces us to heat our homes. And the pressing question is not how to bring warmth into the house, but how to bring it from least losses. Previously, the pipeline was wrapped in glass wool, secured with steel wire, and covered on top with galvanized steel sheets. The material is valuable, so it did not last long on the pipes. Today, polyurethane foam pipes are increasingly used. Thermal insulation is also made from it.

Advantages of PPU:

Stages of installation of polyurethane foam pipes:

1. stripping;
2. welding and quality control;
3. for this purpose a flaw detector is needed;
4. putting on the coupling. It is poured under it polyurethane foam. The coupling heats up and settles. This allows for a tight connection.

The UEC system for the heating main is an additional method of protection. And it consists in preventing major emergency situations and maximizing quick elimination minor damage.

The UEC system: what does it consist of?

Built-in copper wire. It is a conductor through which a signal about damage 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 follows the contour of the pipeline and stretches 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.

Instruments for monitoring and measurement:

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

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

UEC system project - how it happens

The UEC system for polyurethane foam pipes is designed with the ability to connect with existing heating mains, as well as with pipelines that are just being planned.

One of the two signal wires is marked (also known as the main wire). Located to the right in the direction of water movement to its 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 Ohm to 0.015 Ohm;
• for PPU insulation per 300 meters of pipe length - 1 Ohm.

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

Weather:

• measuring instruments are used only in dry and ventilated conditions;
• sealed. Applicable subject to high humidity air.

Territorial:

• end, used at the end points of control;
• unifying. It is used at the points of connection of some sections of the heating main;
• combining with the ability to access stationary detectors;
• passable. In those places where a rupture of the insulating layer was recorded;
• intermediate. It is installed at control points where the lateral 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 coverage area of ​​the monitoring devices.

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

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

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

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

The terminals are installed into the carpet at the end points. Their installation is also possible in central heating points.

The UEC system allows you to monitor the condition of the pipeline, promptly signal a malfunction, and accurately indicate the location of any defect. The presence of the UEC system significantly saves cash and reduces the time spent on pipeline maintenance.

The monitoring system allows you to detect the following defects:

• Damage to a metal pipe (fistula).
• Damage to the polyethylene shell.
• Breakage of signal conductors.
• Shorting signal conductors to a metal pipe.
• Poor connection of signal wires at the joints.

Composition of the UEC system

The operational remote control system is a special set of instruments and auxiliary equipment(which will be further referred to as elements of the UEC system) with the help of which the condition of the pipeline is monitored. The exclusion of any element from the system violates its integrity and regulatory functionality.

The control system includes the following components:

• Signal conductors
• Control and measuring equipment (damage detectors, pulse reflectometer - locator, control and installation device "Robin KMR 3050 DL").
• Switching terminals.
• Connecting cables.
• Ground and wall carpets.
• Materials and equipment for installation.

Signal conductors

Purpose

All pipelines and fittings (tees, bends, valves, fixed supports, compensators) must be equipped with signal conductors. With the help of signal wires (a signal is transmitted through them - a current or a high-frequency pulse) the condition of the pipeline is determined.

Technical specifications

Conductor Configuration

The signal wires, installed inside the thermal insulation layer of polyurethane foam, are pulled parallel to the pipe being manufactured and geometrically positioned at “3” and “9” or “2” and “10” o’clock.

Functional purpose of conductors

The mounted wires are absolutely identical, but according to their purpose they are divided into main and transit wires.
The main wire is a signal conductor that enters all its branches during installation of the heating main. This wire is the main one for determining the condition of the pipeline, as it follows its contour.
A transit wire is a signal conductor that does not enter any branch of the heating main, but runs along the shortest path between the starting and ending points of the pipeline and mainly serves to form a signal loop.

Installation of conductors during construction

During the construction of a heating main, the installation of conductors is carried out at the butt joints of the pipeline.
The installation of the wires must be carried out in such a way that the main signal wire is to the right in the direction of water supply to the consumer on all pipelines, and all side branches must be included in the break of the main signal conductor. It is prohibited to connect side branches to the transit wire.

Connecting wires at joints

The signal wires are connected to each other accordingly: main to main, and transit to transit.
Using pliers, the wires twisted into a spiral are carefully straightened and stretched and, without allowing kinks, are arranged parallel inside.
The wires are cleaned with sandpaper to remove any remaining foam and paint, and then thoroughly degreased.
The wires should be tensioned and excess parts should be cut off so that there is no slack when connecting.
Insert the ends of the wires into the crimp sleeve and crimp the sleeve on both sides using crimping pliers.
After this, the resulting connection must be tinned using an inactive flux, POS-61 solder and a gas soldering iron (or electric, if there is a 220V power supply), the connection of the wires is heated with a soldering iron, after a few seconds it heats up to the melting temperature of the solder.
The connection is sealed correctly when the solder fills the ferrule on both sides.
To check if the connection is correct, you need to pull the signal wires to check if the splice is ok.
Press the wires into the special slots into the wire holders previously attached to the metal pipe.

Description:

A. V. Aushev, General Director of Termoline LLC

S. N. Sinavchian, Ph.D. tech. Sciences, Associate Professor of the Department of RL-6 MSTU. N. E. Bauman

Networks central heating and hot water supply are a thermally insulated metal pipe that creates a sealed circuit for moving liquids under pressure up to 1.6 MPa. In a city, the task of monitoring its tightness is determined both by the need to maintain its functionality, which means reducing coolant losses and saving thermal energy, and by the safety requirements of citizens.

One of the methods for monitoring the tightness of a metal pipeline is to control the pressure in it. However, a number of reasons, such as the presence of coolant flow by the consumer, the dependence of pressure on temperature in a closed volume and the low accuracy of pressure gauges, make this method very crude.

Determination of leaks during ducted and ductless laying of heat pipelines

Heat pipes can be divided into two groups:

• having an additional sealed thermal insulation shell along the entire length (ductless laying),
• with a non-hermetic insulation shell, which mainly performs the functions of its fixation (channel gasket).

Let's consider these groups from the point of view of ensuring the possibility of detecting and localizing the location of a coolant leak.

Channel gasket They are used, as a rule, for pipelines whose insulating layer is not protected by an additional waterproofing shell along the entire length. For channel-laying pipelines, leak detection is only possible using special equipment. Such equipment is acoustic and correlation leak detectors, the operating principle of which is based on determining the location of a powerful source of sound and vibration vibrations when liquid flows outside a sealed circuit.

Thermal imagers are also used, the data of which allows one to determine the location of the maximum level of infrared radiation of the soil, heated by the coolant flowing uncontrollably from the pipeline. Sometimes chemical analysis of soil and Wastewater, determination of the presence of coolant in which indicates a pipeline rupture.

However, in urban conditions, the presence of adjacent communications (where the coolant goes), as well as the unevenness of the depth and surface of the soil above the pipeline, introduce significant difficulties in determining the location of the leak when using thermal imagers and chemical analysis of water. Finding the location of a pipeline rupture during channel laying, as a rule, consists of integrated approach when performing these works. In addition, none of the listed methods can be implemented with cheap, permanently installed equipment, so there is no economically accessible possibility of automatic notification of an emergency situation on the pipeline.

For channelless installation Only pipelines whose thermal insulation layer is protected by an additional external waterproofing shell are applicable. However, this shell not only serves as a barrier to external ground or melt water, but also is an obstacle to the penetration of coolant into the coating if the metal pipe loses its tightness. At the same time, the flow of coolant into the bedding is not accompanied by a powerful release of acoustic noise and vibration, as happens with channel laying, which is the reason low efficiency use of acoustic and correlation methods.

The only way (from those given above for channel-laying pipelines) to determine the presence and location of depressurization of a metal pipeline or outer shell is the use of thermal imagers. However, in a city environment this method cannot be considered accurate, and automation of emergency notification is not available.

Systems for operational remote monitoring of pipelines

The use of an online remote monitoring system (ORMS) for pipelines in polyurethane foam (PUF) insulation is the only possible guaranteed way to monitor the insulation condition of a channel-laying pipeline. SODC is a complex of instrumentation and pipework, consisting of two copper conductors located parallel to the thickness of the insulation metal pipeline along its entire length (Fig.). When the insulation gets wet due to depressurization of the metal pipe and the outer polyethylene sheath, its resistance sharply decreases, which is detected by stationary insulation condition monitoring devices.

According to data from SODC detectors, it is necessary to record them at least once every two weeks. The collection of information is traditionally carried out by employees of the operation service - “crawlers”, whose task is not only to bypass many points, but also to record on paper data from stationary and portable insulation state detectors. The volumes of implementation of polyurethane foam-insulated pipelines equipped with SODC, which are increasing every year, do not allow them to be effectively controlled by bypass, which is the reason for the need to use dispatch systems (see reference).

Benefits of dispatching

Let us note once again that automatic control of the tightness of a metal pipe and the outer shell is implemented only for pipelines in PPU-insulated channel laying, equipped with ODSK. Continuous remote monitoring of the condition of such pipelines has the following advantages over traditional way collecting information:

• Instant notification about changes in the condition of the pipeline and the integrity of the system.

According to clause 9.2: “To promptly identify damage to the pipeline, it is necessary to ensure regular monitoring of the condition of the ODS (at least twice a month) using a detector.” During this time, if a metal pipe breaks, the entire section of the pipeline with PPU insulation may fail. It is possible for water to spread inside the thermal insulation of the pipeline (between the PPU insulation and the shell, as well as the PPU insulation and the metal pipe) over tens of meters in a short time. Effective operation of such sections is impossible in the future; the process of their wetting is irreversible, which leads to the need to re-lay tens of meters of pipeline.

We especially note that the loss of integrity of a metal pipe in PPU insulation is not accompanied by a sharp drop in pressure in the system, as happens in channel-laying pipelines. This is due, firstly, to the tightness of the polyethylene shell, and secondly, to the channelless method of laying the pipeline in PPU insulation. The pressure in the pipe can be maintained even when network water spreads along the pipeline for tens of meters. This fact indicates the impossibility of detecting an emergency situation on a pipeline in polyurethane foam insulation, except with the help of a working ODS. Within two weeks of not taking readings from the detectors, the soil may be washed away, which will lead to the collapse of the load-bearing layers of the soil, and this, in turn, in a city environment can lead not only to great material damage, but also to human casualties.

• Screening out false calls.

The specificity of the work of the “crawler” determines the possibility of them recording false information or the failure to transmit real information about the readings of the detectors to the emergency services. Often, when response teams arrive, the detector readings correspond to the normal operation of the pipeline, and a false call is associated with the incompetence of the “inspector”. But it is worse if he did not record or transmit information about the accident on the highway. Operations service employees or a third-party organization (working under a contract) responsible for taking readings on site using a walk-through method may actually not visit the controlled objects, while they themselves record the “normal” state of the pipeline, since they know that at this stage no one is watching controls. Then the time for soil erosion exceeds two weeks, which significantly aggravates the consequences of a pipeline accident and increases the length of the required replacement. By excluding the human factor from the emergency notification chain, we significantly increase the reliability of PPU-insulated pipelines.

• Elimination of the corruption component.

A situation is possible when an employee of the operation service, responsible for taking readings on site, for some reason deliberately tries to hide or distort the real state of the pipeline - for example, the same employee commissioned a pipeline in poor quality or with a faulty SDSK. When organizing remote control it is possible to eliminate the corruption component that occurs when pipelines are accepted for operation. Such an approach will also provide more high quality of delivered pipelines, since one employee takes it into operation, and controls it through the PD by another.

• Application of multi-level detectors.

As a rule, single-level stationary damage detectors are installed on heating mains. They signal that the pipeline is wet, at which its insulation resistance decreases only to 5 kOhm. The use of multi-level detectors with current output makes it possible to detect pipeline defects at an early stage of its formation. Detection of the insulation resistance of the monitored pipeline occurs in six ranges, the upper of which corresponds to the ideal insulation state (more than 1 MOhm). The speed at which the resistance decreases from the upper range to the lower (less than 5 kOhm) indicates the size of the defect: the higher the speed, the more significant the pipeline defect.

• Ease of perception of received information, its processing and storage.

Today, all information received from “crawlers” is stored mainly on paper and is practically not amenable to statistical processing. The data collected using the dispatch system is not only more voluminous, complete and reliable, but also makes it possible to process it using various mathematical analysis algorithms. This allows you to filter out seasonal changes pipeline insulation conditions, false alarms, errors caused by human factors. Using a special software allows you to automatically generate reports on the condition of pipelines, monitor the nature and speed of response of personnel on site, and, when a sufficient sample has been accumulated, conduct a statistical analysis of information on the use of pipelines with polyurethane foam insulation.

• Flexibility of the dispatch system.

The stability and quality of operation of any telemetry system depend on proper organization architecture of interaction of its components. The usual structure of a dispatch system involves collecting data from geographically distributed controlled objects (often of the same type) into a single center. There are other options: multi-level construction of control rooms, local nodes for collecting or relaying data and others, but they do not change the essence of the centralized construction of the system. Moreover, the size of the system, depending on the object, can be either small (in the case of a block, an enterprise) or gigantic (branch, city, region).

• Economic expediency.

The role of automation and modernization of technological equipment of utility networks in modern reality is not only to improve the quality of service to the population, but also to reduce the cost of providing heat and heat transport services. hot water. Important economic factors for reducing operating costs are the absence of a wage fund for “linemen”, their material support, the absence of the need for training, control and accounting. There are also no additional difficulties associated with organizing access for “inspectors” to the premises where the detectors are installed. Of particular importance is the speed of delivery of information about an emergency situation, which is the main positive economic indicator.

The listed advantages of dispatch systems for the readings of pipeline condition detectors in polyurethane foam insulation became the reason for their use back in the early 2000s. The first mentions of positive effects were published in. On this moment in one of the heating networks of the Moscow region, several data transmission systems operate simultaneously, exchanging information both cable lines, and via GSM channel.

Methods for implementing data transmission systems

First way is the integration of stationary damage detectors as primary sources of information into the architecture existing systems telemetry performing monitoring and control tasks technological equipment heating points. The implementation of this method is possible if the SODC detector has the hardware ability to transfer data to the input lines of a remote controller (the detector must be equipped with special outputs for data transfer such as “current output” or “dry contact”). Heat network employees must have high professional skills to successfully visualize, analyze and store detector data on the control panel.

Both cable and GSM data transmission channels are used. This method of data transmission has been implemented for monitoring and managing a number of heating points in Moscow, Mytishchi, Reutov, St. Petersburg, and Astana.

Second way focused on the use of GSM telemetry systems, which have found application in the electric power industry, gas industry, banking sector, complexes security and fire alarm system. High competition between manufacturers of such complexes is the reason for the emergence of large quantity reliable and cheap GSM controllers, the use of which for monitoring the condition parameters of pipelines in polyurethane foam insulation is a cost-effective and easy-to-implement solution. The main requirements for GSM telemetry systems are the ability to transfer data from the detector to the controller and the availability of software control panel. This software must provide:

• continuous unlimited control over remote objects;
• visualization of the location of controlled objects on a map of a populated area;
• visual and acoustic notification in case of an accident;
• individual configuration of the “Alarm” signal level for each object;
• stability of data transmission when duplicating various transports (modem connection, SMS, voice connection);
• the ability to transmit and visualize data from security sensors, temperature sensors, pressure sensors, etc.;
• the ability to automatically poll objects;
• sending SMS to the phones of responsible persons in case of emergency situations;
• personalized management and storage of information about operator actions in the event log;
• user-friendly interface, smooth operation, easy operation, etc.

The switching of GSM controllers with detectors, installation and configuration of remote controllers is carried out independently by employees of instrumentation departments or special units, which is greatly simplified due to the availability of detailed instructions. The task of creating a local dispatch console (LDP) at the level of a heating network enterprise is easy to accomplish, as it involves installing and configuring free and intuitive software. This method implemented by enterprises of Novosibirsk, Mytishchi, Zheleznodorozhny, Dmitrov.

Third way dispatching the readings of SODK detectors is proposed in . If the operating organization does not see the need to create its own LDP (lack of proper funding, personnel or third-party organization appropriate level preparation, small number of objects), it is possible to use the services of the integrated dispatch console (UDP). The EDP, located in Shchelkovo, Moscow Region, receives information from GSM controllers configured to work with EDP, installed on the territory of the Russian Federation, the Republic of Kazakhstan and the Republic of Belarus.

Emergency notification of the responsible person of the operating organization in the event of an emergency occurs in any way convenient for him ( Personal Area on the ODP website, Email, cellular telephone, dispatch service, etc.). A scheduled survey is also provided according to a schedule approved by the operating organization.

The operating organization must ensure safety at the installation site of the detector and remote GSM controller installed equipment, his uninterruptible power supply and a satisfactory level of GSM signal (if necessary, use a repeater).

Subsequently, remote transfer of data to a newly created LDP by the operating organization is possible. Thus, the use of DDP services becomes a test option for organizing your own LDP.

The method of dispatching detector readings is determined at the level of design work, since the specification, and therefore further financing, is formed by a specialist from the design organization, therefore one of the important tasks of the operating organization is to formalize the complete terms of reference indicating the requirements for dispatching the designed pipeline.

Based on the provided technical specifications, the designer must determine the location and configuration of the pipeline control point equipped with a damage detector. Required condition The constant functioning of such a control point is the presence of a 220 V, 50 Hz power supply. Complete sets of control points for operating in stand-alone mode are also supplied, however, their use is possible only in exceptional cases, since regardless of the type of power source ( a solar panel or batteries) kits for battery life provide only periodic monitoring of the pipeline insulation condition, which is the main way to reduce energy consumption.

The experience of implementation and delivery of equipment for dispatching the readings of pipeline condition detectors in polyurethane foam insulation indicates timeliness, sufficient high level equipment and economic efficiency of this area. A professional approach allows you to fully automate the notification process emergency situations on pipelines of heating networks, which is only possible for pipelines equipped with ODS. At the same time, it is proposed various ways implementation of monitoring of detector readings for various levels vocational training heating network personnel.

Literature

1. STO 18929664.41.105–2013. System for operational-remote monitoring of pipelines with thermal insulation made of polyurethane foam in a polyethylene shell or steel protective coating. Design, installation, acceptance, operation.
2. Kashinsky V.I., Lipovskikh V.M., Rotmistrov Ya.G. Experience in operating pipelines in polyurethane foam insulation at OJSC Moscow Heating Network Company // Thermal Energy. 2007. No. 7. pp. 28–30.
3. Kazanov Yu. N. Organizational and technical modernization Heat supply systems of the Mytishchi region // Heat supply news. 2009. No. 12. pp. 13–26.
4. Termoline LLC. Album technical solutions on the design of operational-remote monitoring systems for pipelines in polyurethane foam insulation. M., 2014.