PREHEATING DEVICE FOR WELDING OF OIL, GAS AND GEOTHERMAL WELLHEADS OF VARYING DIAMETERS AND THICKNESSES

Abstract

The present invention relates to a preheating device for welding oil, gas, and geothermal wellheads of varying diameters and thicknesses which is applicable to the oil, gas, and geothermal industry. The preheating of head and coating pipes to be welded do not cool down quickly. The cooling speed reduction prevents structures or joints from being less susceptible to cracking by maintaining the necessary heat thus preventing the integrity of the joints from being exposed. The preheating of head and coating to be welded maintains a uniform and constant temperature avoiding temperature changes, thus making the structures or joints less susceptible to cracking by maintaining the necessary heat and preventing the integrity of the joints from being exposed.

Claims

1. A preheating device for welding of heads and coating for oil, gas, and geothermal wells of varying diameters and thicknesses, wherein the preheating device is an electric preheater that facilitates weld joining of a head that is installed on a coating pipe, the preheating device comprises: a steel body made of rolled sheet steel; a top cover wherein the top cover has a clamping hook that allows to variation and adjustment of a height of the preheating device for welding of heads and coating for oil, gas, and geothermal wells of variable diameters and thicknesses with respect to welding to be performed; a temperature controller, which determines and regulates a temperature required to achieve a given weld; and a bottom cover.

2. The preheating device for welding of heads and coating for oil, gas, and geothermal wells of varying diameters and thicknesses, according to claim 1, wherein the rolled sheet steel body comprises within it at least two flexible ceramic heating elements.

3. The preheating device for welding of coating heads and coating for oil, gas, and geothermal wells of variable diameters and thicknesses, according to claim 2, wherein an inside of the steel body is divided equidistantly by at least two rolled steel plates parallel to each other and on which the at least two flexible ceramic heating elements and a ceramic fiber insulator are placed and installed.

4. The preheating device for welding of heads and coating for oil, gas, and geothermal wells of varying diameters and thicknesses, according to claim 1, wherein the top cover comprises a plurality of flexible ceramic thermal resistor terminals and thermocouple or thermistor terminals.

5. The preheating device for welding of coating heads and coating for oil, gas, and geothermal wells of varying diameters and thicknesses, according to claim 4, wherein the top cover comprises at least two thermocouple or thermistor terminals, and wherein the at least two thermocouples are used for sensing a lower temperature near the coating and at the least two thermocouples for the temperature is located at a top near a coating body in a welding zone.

6. The preheating device for welding of coating heads and coating for oil, gas, and geothermal wells of variable diameters and thicknesses, according to claim 1, wherein the temperature controller sets a preheating temperature that allows a required temperature to be reached and to be carried out in a controlled and constant manner throughout a welding process, thus preventing a weld from fracturing or crystallizing due to temperature differences, which would lead to leaks in weld joints.

7. The preheating device for welding of weld heads and coating for oil, gas, and geothermal wells of varying diameters and thicknesses, according to claim 6, wherein the temperature controller allows reaching temperatures ranging from 204° C. to 370° C.

8. The preheating device for welding of heads and coating for oil, gas, and geothermal wells of varying diameters and thicknesses, according to claim 7, wherein the temperature controller will digitally control via a physical or a wireless connection, working intervals, setting a minimum, maximum and safety limit interval.

9. The preheating device for welding of heads and coating for oil, gas, and geothermal wells of variable diameters and thicknesses, according to claim 4, wherein a ceramic fiber insulator limits heat dissipation towards a center of the preheating device to avoid heat loss, thus dissipating all heat towards an external part of the preheating device and optimizing an operation of the preheating device.

10. The preheating device for welding of heads and coating for oil, gas, and geothermal wells of varying diameters and thicknesses, according to claim 1, wherein a plurality of flexible ceramic thermal resistor terminals and thermocouple or thermistor terminals are located within an inner chamber of the preheating device so that the plurality of flexible ceramic thermal resistor terminals and thermocouple or thermistor terminals can be represented by an identifier.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0021] FIG. 1 is a view of the preheating device for pipes of variable diameters and thicknesses placed inside the pipe.

[0022] FIG. 2 is a view of the preheating device for pipes of variable diameters and thicknesses partially segmented showing the upper and inner components of the device, inserted in the pipe to be welded.

[0023] FIG. 3 is a view of the partially segmented preheating device for tubes of variable diameters and thicknesses showing the upper and inner components of the device, outside in the tube to be welded.

[0024] FIG. 4 is a top perspective view of the preheating device for tubes of variable diameters and thicknesses inserted into the tube to be welded showing the upper devices.

[0025] FIG. 5 is a view of the preheating device for welding of heads and coating for oil, gas, and geothermal wells of variable diameters and thicknesses in its mating position to the partially cut head and pipe to be welded.

[0026] FIG. 6 is a cutaway view of the oil well coating and tubing head welding preheater showing its internal components.

[0027] FIG. 7 is a bottom cutaway view of the oil well coating and tubing head welding preheater showing its internal components.

DETAILED DESCRIPTION OF THE INVENTION

[0028] It is an object of the present invention to provide a preheating device for welding of heads and coating for oil, gas, and geothermal wells of variable diameters and thicknesses (1), wherein said device is an electric preheater wherein, by way of illustration but not limitation, it may be formed by flexible ceramic thermal resistors (7).

[0029] It is an object of the present invention that the preheating device for welding of heads and coating for oil, gas, and geothermal wells of variable diameters and thicknesses (1) has in its upper part a top cover (2) where the top cover has a fastening hook (6) that allows to vary and adjust the height of the preheating device for welding of heads and coating for oil, gas and geothermal wells of variable diameters and thicknesses with respect to the welding to be performed.

[0030] It is another object of the present invention that emanates from the top cover (2) and protrudes on its surface, the flexible ceramic thermal resistor terminals (5), and the thermocouple or thermistor terminals (3 and 4) are provided.

[0031] It is an object of the present invention that the preheating device for welding of heads and coating for oil, gas, and geothermal wells of variable diameters and thicknesses (1) facilitates the joining by welding of a header (14) which is installed on a coating pipe (15), wherein the header (14) and the coating pipe (15) require for better welding between both elements the supply of heat by the preheating process. The preheating process requires reaching temperatures of 400° F. to 600° F. (204° C. to 370° C.).

[0032] It is an object of the present invention to have a temperature controller where the preheating temperatures allow reaching the required temperature and this is carried out in a controlled and constant way during the whole welding process, which allows avoiding that the welding due to temperature difference fractures or crystallizes which would lead to leaks in such joints.

[0033] It is another object of the invention that the electric preheater has specific characteristics for each diameter of head and coating for the different stages of drilling oil, gas, and geothermal wells.

[0034] It is another object of the present invention that the preheating device for pipes of varying diameters and thicknesses comprises a steel body of rolled sheet steel (8).

[0035] It is another object of the present invention that the interior of the device comprises at least two flexible ceramic thermal resistors (7) and a ceramic fiber insulator (13).

[0036] It is another object of the present invention that the ceramic fiber insulator (13) limits heat dissipation toward the center of the device to avoid heat loss, thereby dissipating all heat toward the outside of the device and optimizing performance.

[0037] It is another object of the present invention that the device in its upper part comprises at least two thermocouple or thermistor terminals (3 and 4), wherein at least two thermocouples are used for sensing the lower temperature which is close to the coating pipe (15) and at least two thermocouples for the temperature in the upper part which is close to the head body in the welding zone.

[0038] It is another object of the present invention that, once the electrical preheating is connected to the power source, it will be controlled digitally, wherein the working intervals are programmed, establishing the minimum, maximum and safety limit intervals.

[0039] It is another object of the present invention that the controller will control in a digital manner by a physical or wireless connection of the working intervals, establishing the minimum, maximum, and safety limit intervals.

[0040] It is another object of the present invention that the control device has a temperature vs. time register.

[0041] It is another object of the present invention that the preheating device for welding of heads and coating for oil, gas, and geothermal wells of varying diameters and thicknesses (1) is designed for optimum heat transfer and coating, wherein the dimensions are established by API (American Petroleum Institute) Standards, for heads and coating pipes, for which the free passage for thicker coating is taken.

[0042] It is another object of the present invention that the preheating device for welding of heads and coating for oil, gas, and geothermal wells of variable diameters and thicknesses (1) is divided equidistantly by at least two rolled steel plates (12) parallel to each other and on which the flexible ceramic heating elements (7) and the ceramic fiber insulator (13) are placed and installed.

[0043] It is another object of the present invention that the preheating device for welding of coating heads and coating for oil, gas, and geothermal wells of varying diameters and thicknesses has at its lower end a lower cover.

[0044] It is another object of the present invention that the preheating device for welding of heads and coating for oil, gas, and geothermal wells of varying diameters and thicknesses has quick connectors for the flexible ceramic thermal resistors and the thermocouple or thermistor terminals within the same inner chamber of the device so that they can be represented by an identifier either (3) or (5).

TABLE-US-00001 Coating Coating pipe Electric pipe clearance in preheater outside diameter inches diameter in inches 20” 18.543 18.343 16” 14.127 13.927 13 5/8” 12.188 11.988 13 3/8” 12.003 11.803  9 5/8” 7.875 7.676  7 5/8” 5.876 5.676