TECHNICAL FIELD

The invention relates to a heating system for producing double-layer and copper- coated steel tubes, in which the tube layers are joined together.

PRIOR ART

Currently, walls of a steel sheet layer to be used in the welding process is coated with a copper material. Copper-coated steel sheets are rolled in a tube forming unit and to obtain a cold double tube form. The double layer tubes with copper layer are heated to a temperature above the melting temperature of the copper in a furnace. In the furnace, the tube moves at a predetermined feed rate are joined under a protective gas.

The hot tubes from the joining process, at the end of an annealing unit cool down to obtain seamless double-layer tube.

TR201000280 discloses a copper coating method using electrolysis on the sheet steel layer to obtain a two-layer tube from the obtained copper coated plate, by reaching a welding temperature of the two-layer tube, heating at the welding temperature, and double-layer tube production process by welding with the heated copper at optimum welding conditions.

BRIEF DESCRIPTION OF THE INVENTION

The object of the invention is to control joining temperature in a heating system where the layers of the tube are welded for the production of double-layered tubes.

Another object of the invention is to control the melting temperature of the copper layer in the double-layer steel tube in the heating system. In order to achieve the aforementioned object, the invention is a heating system for manufacture of copper coated double-layer steel tubes having a casing in which the roll-wrapped tube forms are heated to a predefined temperature value. The heating system comprises a sensor configured in an outer portion of the casing such that the sensor is able to determine temperature value inside the casing. Thus, it is ensured that the temperature value in the casing is sensed from the outer part of the casing. In this way, during the production of double-layer tubes, the temperature of the joining in the heating system is controlled. Here, the term “joining” refers to the “welding” process. Here, it is a “welding temperature”, which is meant by the “temperature of the joining”. Joining temperature in a double-layer steel tube is the melting temperature of the copper layer.

In a preferred embodiment, the sensor is being positioned such that facing towards a joining point of the tube forms in the casing. Thus, the temperature control is provided by a joining point of the tube. By the joining point, it is meant that a point where the steel layer and copper layer meet with the welding process in double-layer tube in the casing.

In another preferred embodiment, there is a first window arranged on the casing, corresponding to the sensor. Thus, a see through opening inside the casing is provided for the sensor.

In another preferred embodiment, the first window is configured on an upper wall of the casing. Thus, the sensor is provided to observe the inside of the casing from the upper wall.

In another preferred embodiment, a bar is extending away from the casing. Thus, it is ensured that the sensor is positioned at a location away from the casing, therefore the sensor is not affected by the high temperature.

In another preferred embodiment, a retaining element is disposed on the bar, which at least partially surrounds the sensor. Thus, it is ensured that the sensor is secured at least partially by winding. In another preferred embodiment, the casing has a second window from which an interior is seen. Thus, it provides a second window in which an operator can easily see the enclosure. In this way, the operator can visually control the joining process of the tube.

In another preferred embodiment, the casing comprises an inlet into which the tube form of the roll is fed to the heating system. In this way, an inlet is provided from which the tube enter the casing.

In another preferred embodiment, the casing comprises an outlet of copper-coated double-layered steel tubes from the heating system. In this way, the outlet of the copper-plated double-layer steel tubes can be removed from the casing.

In another preferred embodiment, a handle is provided allowing adjustment of the temperature value within the casing. Thus, a handle is provided in which the operator can adjust the temperature inside the casing.

In another preferred embodiment, there is a control element is configured to measure the temperature value provided by the sensor. Thus, a control element receive the temperature information provided by the sensor.

In another preferred embodiment, there is a display configured to indicate the temperature value provided by the control element. Thus, a display is provided for the operator to visually identify the temperature value inside the casing.

In another preferred embodiment, the sensor is a temperature sensor that measure the temperature value from a predefined distance.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1 shows a representative perspective view showing the heating system according to the invention. Figure 2 shows a representative front view showing the heating system according to the invention.

Figure 3 shows a representative view of the double-layer tube obtained after joining in the heating system according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

Figure 1 shows a representative perspective view showing a heating system (1 ) according to the invention. The heating system (1 ) comprises in its most common form a casing (10) and a control unit (18). A display (19) is provided on the control unit (18) which provides the user with visual data. A first window (15) is provided on an upper wall (13) of the casing (10). In a possible embodiment, the first window (15) is provided in a circular form. A second window (16) is described on the front wall (14) of the casing (10) which is accessible from the front side of the user's heating system (1 ). In a possible embodiment, the second window (16) is provided such that the front wall (14) is in a horizontal direction. The first window (15) and the second window (16) are covered by a transparent material in the structure showing the interior of the casing (10). In a possible embodiment, said transparent material is a glass. The side faces of the casing (10) which are mutually opposite each other have an inlet (1 1 ) and an outlet (12). A hollow tube extends from the inlet (1 1 ) of the casing (10) to the outlet (12). The tube has a circular cross-section. The tube forms, which are wound into a roll into the casing (10) from the inlet (1 1 ), emerge as a double layer tube (30) from the outlet (12). In more detail, the roll-shaped tube emerge as a double-layer tube (30). A representative view of the double-layer tube (30) coming out of the heating system (1 ) is shown in Figure 3. In a possible embodiment, said double-layer tube (30) is a copper-coated steel tube. The copper-coated steel tube has a steel layer (31 ), a copper layer (32) and a joining section (33) with a steel layer (31 ) and a copper layer (32). Said joining section (33) is the portion of the double layer tube (30) welded.

In the heating system (1 ), there is a bar (21 ) provided with the casing (10) in the upper wall (13) with the first window (15). A retaining element (22) is positioned on one side of said bar (21 ) away from the upper wall (13). The retaining element (22) secures a sensor (17). In more detail, the retaining element (22) is configured to at least partially surround the sensor (17). In this way, the sensor (17) is located in an outer portion of the casing (10).

Referring to Fig. 2, the sensor (17) is positioned to correspond to the first window (15). In this way, the sensor (17) is positioned in such a way that a joining point (K) of the tube in the casing (10) is visible. Said joining point (K) is the point at which the copper layer (32) and the steel layer (31 ) are joined to the welding process. This is achieved by melting copper. The sensor (17) positioned to display the joining point (K) is a temperature sensor that senses the temperature value from a distance. The sensor (17) is connected to a control element (23) in the control unit (18) with a first line (L1 ). The temperature value sensed by the sensor (17) is transmitted to the control element (23) by the first line (L1 ). The temperature value received by the control element (23) is transmitted to the display (19) by a second line (L2). In a possible embodiment, said control element (23) is a printed circuit board.

In the heating system (1 ), the casing (10) has a adjustment mechanism in which the temperature value is adjusted. There is a handle (20) in the adjustment mechanism. The temperature value in the casing (10) increases as the user enables the adjustment mechanism to move in a first direction (a) by means of the handle (20). Again, the temperature value in the casing (10) decreases with the user enabling the adjustment mechanism to move in a second direction (b) via the handle (20). In this way, the user adjusts the temperature value in the casing (10) by means of the handle (20) and can visually see the temperature value sensed by the sensor (17) on the display (19). In a possible embodiment, said temperature value is in the range of a minimum of 1000 0C and a maximum of 1200 0C. In a possible embodiment, the sensed temperature is a melting temperature of the copper.

REFERANCE NUMBERS

1. Heating system

10. Casing 1 1. Inlet 12. Outlet

13. Upper wall

14. Front wall

15. First window 16. Second window

17. Sensor

18. Control unit

19. Display

20.Handle

21. Bar

22. Retaining element

23. Control element 30. Double-layer tube 31.Steel layer

32. Copper layer

33. Joining section a. First direction b. Second direction K. Joining point

L1.First line

L2. Second line