RU168225U1 - Device for electric heating of pipelines - Google Patents

Abstract

The utility model relates to electrical engineering and electrical heating systems, namely, it can be used to heat pipelines of various lengths. The technical result is the ability to control the temperature of the heated object in a given interval. The essence of the utility model: a device for electric heating of pipelines contains an AC power source, at least one heating tube of ferromagnetic material, inside which a conductor and a switching device are stretched. The switching device is controlled by a control system comprising at least one temperature sensor and a control unit. Depending on the number of heating tubes, the conductor is divided into sections and fastened by couplings, which are located in the broaching boxes. The heating tube and conductor are connected at one end to the outputs of the switching device, and at the other end to each other. The inputs of the switching device are connected to an AC power source.

Description

The utility model relates to electrical engineering and electrical heating systems, namely, it can be used to heat pipelines of various lengths.

The advancement of the main oil and gas producing regions of the country to the North posed a number of urgent technical tasks for specialists in the gas and oil industry.

One of these tasks is to ensure reliable operation of the infield and inter-site pipeline transport. The formation of asphalt-resinous, paraffin deposits and ice plugs in gas pipelines and oil pipelines in powerful northern fields, great difficulties in operating the water intake facilities of fields in permafrost, water pipelines and drains all put on the agenda the need to develop simple, inexpensive and reliable devices for heating pipelines and other oil and gas facilities, devices capable of a small amount of additional energy reported from the outside, automatically compensate for ruzhnye heat loss, ensure reliable operation of the fishing pipeline transport systems and equipment.

A device for electric heating of technological objects by eddy currents [RU 154343 U1 IPC Н05В 6/06, published on 08/20/2015], containing an AC power source, at least one heating tube made of ferromagnetic material, inside which a conductor and a switching device, characterized in that the ends of the conductor are connected to the outputs of the switching device, and the inputs of the switching device with an AC power source, control of the switching device etsya control system comprising at least one temperature sensor and a control unit, depending on the geometry of the heated object and the number of heater tubes conductor is divided into sections and bonded couplings which are arranged in boxes broaching.

The disadvantage of this utility model is the high material consumption due to the connection of both ends of the conductor to the outputs of the switching device.

A device for heating pipelines is known [RU 43941 U1 IPC F17D 1/18, Н05В 3/48, published 02/10/2005], comprising, according to claim 1, a heating element made in the form of a pipe made of ferromagnetic material, inside of which an electrical conductor is placed equipped with a protective element, said pipe and conductor connected to the terminals of the AC power source, characterized in that the protective element is made in the form of a corrugated polymer tube.

The disadvantage of this utility model is the inability to control the temperature of the heating element, made in the form of a pipe made of ferromagnetic material, as a result of which the pipeline may overheat.

The objective of the utility model is to create a device for electric heating of pipelines, the implementation of which achieves the technical result, which consists in the ability to control the temperature of the heated object in a given interval.

The specified technical result is achieved in that the device for electric heating of pipelines contains an AC power source, at least one heating tube of ferromagnetic material, inside which a conductor and a switching device are stretched, the switching device is controlled by a control system comprising at least one temperature sensor and control unit, depending on the number of heating tubes, the conductor is divided into sections and fastened by connecting uftami which are arranged in boxes broaching, the heating tube and the conductor is at one end connected to the outputs of the switching device and the other end with each other, the input switching device coupled to a source of AC power.

In FIG. 1 - shows an electrical circuit containing a power source and a heating tube.

In FIG. 2 shows a simple block diagram of an electric heating control system.

In FIG. 3 - shows a device for electrical heating mounted on a pipeline.

Device for electric heating of pipelines, at least one heating tube 1 made of ferromagnetic material (Fig. 1, 3). The length and number of heating tubes 1 depend on the parameters of the pipeline 7, for example, length. The heating tubes 1 are interconnected by welding. Inside the heating tube 1, a conductor 2 is stretched, which serves for the flow of electric current (Fig. 1, 3). The heating tube 1 and conductor 2 at one end are connected to the outputs of the switching device 3, and the other end to each other. The inputs of the switching device 3 are connected to an AC power source 4, thus enabling or disabling the electrical heating system.

The control of the switching device 3 is carried out by a control system including at least one temperature sensor 5, a control unit 6 (Fig. 2). The temperature sensor 5 is installed on the surface of the pipeline 7, to determine its temperature (Fig. 3). The temperature sensor 5 is connected to the control unit 6, for example by cable or by radio signal. Thus, the control system includes devices that measure readings (temperature sensor 5), a device that analyzes (control unit 6) and gives a signal to close or open the switching device 3. To reduce friction when pulling the conductor 2 through the heating tubes 1 at a large number of them or the complex geometry of the heated object, broaching boxes 8 and couplings 9 (Fig. 3) can be applied, ensuring the splitting of the conductor 2 into sections of shorter length, thereby facilitating installation of electric heating system.

A device for electric heating of pipelines works as follows.

With a decrease in ambient temperature, heat is lost from the pipeline 7 through thermal insulation. As a result, the temperature of the pipeline 7 is reduced. The temperature sensor 5, mounted on the surface of the pipeline 7 (Fig. 3), transmits data to the control unit 6, which analyzes them and gives a signal to close or open the switching device 3. When the switching device 3 is closed, a closed loop is formed from the heating tube 1 and the conductor 2, which is connected to a power source 4 (Fig. 1, 3). The electric current Ip flowing through the heating tube 1 and conductor 2 heats them and the generated heat is transferred to the pipeline 7 (Fig. 1). Since the heating tube 1 is made of a ferromagnetic material, for example, steel grade 3, electric current flows mainly on its inner surface, provided that the thickness of the heating tube 1 is greater than the thickness of the skin layer. On the outer surface, the electric potential is zero and the heating tube 1 can be grounded.

The thickness of the layer over which eddy currents are distributed is determined by the formula:

- частота сети, Гц.where δ is the layer thickness, mm; μ is the magnetic permeability of the substance, GN / m; μ ₀ - magnetic constant, GN / m; σ is the electrical conductivity, S / m;

- network frequency, Hz.

When the temperature of the pipeline 7 reaches the set value, the control unit 6 gives a signal to open the switching device 3. Thus, the temperature of the heated object is monitored to prevent overheating.

Claims (1)

A device for electric heating of pipelines containing an AC power source, at least one heating tube of ferromagnetic material, inside which a conductor and a switching device are stretched, the switching device is controlled by a control system comprising at least one temperature sensor and a control unit , depending on the number of heating tubes, the conductor is divided into sections and fastened by couplings, which are located in the broaching box x, characterized in that the heating tube and the conductor at one end are connected to the outputs of the switching device, and at the other end - to each other, the inputs of the switching device are connected to an AC power source.

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