Electric heating wire inlay structure of electric heating head of electric heating tool and electric heating head adopting the structure

Abstract

The utility model relates to an electric heating wire inlay structure of electric heating head of electric heating tool used in oil and gas field pipeline, including heating part and electric heating wire, the groove is carved on the outer peripheral surface of heating part, the depth of groove is greater than the diameter of electric heating wire, the metal wire is inlaid on the top of electric heating wire in groove still, the utility model discloses inlay low hardness metal wire on the top of electric heating wire in the groove of heating part, both avoid short circuit damage caused by the wear of electric heating wire protection skin, improve heat conduction efficiency, prevent electric heating wire from coming off simultaneously, still relate to a kind of electric heating head using the inlay structure structure, the heating part of electric heating head is cylinder, the thickness of cylinder is greater than the depth of the groove, the part of more than two-thirds of the groove is distributed around the cylinder in spiral shape, structure is simpler, and manufacture is easier.

Description

Technical Field

[0001] This utility model relates to the field of oil and gas field exploration and development technology, and in particular to a heating wire inlay structure for an electric heating tool used in oil and gas field pipelines, and an electric heating head using the same structure. Background Technology

[0002] In oil exploration, development, and well workover operations, numerous pipelines are used, including underground oil, gas, and water well tubing and casing, as well as surface pipelines transporting oil, gas, water, or mixtures thereof. These pipelines often employ electric heating tools for cleaning and scraping. Each of these tools includes a heating head used to generate heat and clean and scrape the inner wall of the pipeline. The heating head typically includes a wiring compartment for connecting heating wires, sensors, and other wiring. The wiring compartment also has threaded connectors for sealing the power supply and other functional components of the heating tool. The heating head also includes a heating element used to heat, scrape, and clean deposits from the pipeline's inner wall. Because the pipeline's inner wall is circular, this heating element usually has a cylindrical section on its outer periphery for better fit. The heating head also includes a connecting section for connecting the wiring compartment and the heating element. This connecting section has a flow channel to discharge debris cleaned or scraped during the operation. Current electric heating tools embed the heating wire within the heating element of the heating head. Before embedding the heating wire, grooves are etched into its outer surface, and then the heating wire is pressed into the grooves. The metal protective sheath of the heating wire is usually very thin, sometimes only about 0.3mm. In actual operation, the heating wire embedded in the grooves on the outer surface is easily worn. In severe cases, the metal protective sheath can be worn through, leading to a short circuit in the internal circuitry of the heating wire and causing damage. In addition, existing heating heads are composed of two or more concentric cylindrical segments of the same radius, making the grooving and embedding path of the heating wire complex and requiring multiple sets of heating wires. Summary of the Invention

[0003] To address the above problems, this utility model proposes a novel heating wire embedding structure for the heating head of an electric heating tool, and a heating head employing this structure. Wherein: A heating wire inlay structure for an electric heating tool heating head includes a heating element and a heating wire. The outer peripheral surface of the heating element is engraved with a groove, the bottom of which is arc-shaped. The heating wire is inlaid in the groove and closely adheres to the bottom of the groove. Its characteristic is that: The depth of the groove is between 1.5 and 2.5 times the diameter of the heating wire; Inside the groove, a metal wire is also embedded above the heating wire.

[0004] Furthermore, the heating wire inlay structure of the heating head of the electric heating tool is characterized in that the hardness of the metal wire is lower than the hardness of the heating part and the heating wire.

[0005] Furthermore, the heating wire inlay structure of the heating head of the electric heating tool is characterized in that the metal wire includes copper wire, aluminum wire, or copper alloy wire or aluminum alloy wire.

[0006] Furthermore, the heating wire inlay structure of the heating head of the electric heating tool is characterized in that the metal wire includes copper wire.

[0007] Furthermore, the heating wire inlay structure of the heating head of the electric heating tool described above is characterized in that the top of the groove is provided with a constriction, the size of which is between 85% and 99% of the diameter of the heating wire.

[0008] This utility model also proposes a heating head with a heating wire inlay structure using the aforementioned heating tool heating head, including a wiring compartment, a heating part, and a connecting part. The heating part of the heating head is cylindrical, with a thickness greater than the depth of the groove, and more than two-thirds of the groove is spirally distributed around the cylinder. The connecting part consists of two parallel and identical columns, each column having its ends connected to the wiring compartment and the heating part, respectively. The two columns are symmetrically distributed relative to the axis of the cylinder. The two columns are separated by at least 20mm to form a flow channel.

[0009] Furthermore, the heating head is characterized in that the inner conductor of one end of the heating wire embedded in the groove is reliably electrically connected to the outer sheath of the heating wire at that end, and the end is sealed to external moisture.

[0010] Furthermore, the heating head is characterized in that the inner edge of the end of the cylinder facing away from the wiring compartment has a chamfer of no more than 35°, so that the end forms a sharp outer edge.

[0011] Furthermore, the heating head is characterized in that the curve formed by the outer edge of the end is a circle perpendicular to the axis of the cylinder or an ellipse not perpendicular to the axis.

[0012] The heating wire inlay structure of the heating head of the electric heating tool proposed in this utility model effectively overcomes the problem that in actual operation, the heating wire, embedded in the groove on the outer surface, is easily worn. In severe cases, the metal protective sheath is worn through, leading to a short circuit and damage to the internal circuit of the heating wire. At the same time, it improves the heat transfer efficiency and heat utilization rate of the heating wire because it increases the contact area between the heating wire and the heating element, thereby improving heat transfer efficiency.

[0013] The heating head proposed in this invention employs a heating wire inlay structure. Because the cylinder has a completely closed cylindrical surface, continuous grooving and wire inlay are possible, simplifying processing and operation. Furthermore, the use of a single-end inner conductor connected to the outer sheath and a sealing method makes it possible to use non-intersecting spiral grooving and heating wire inlay. This ultimately solves the problems of complex grooving and inlay paths and the use of multiple sets of heating wires in existing heating heads where the heating element consists of two or more concentric cylindrical segments of the same radius. The structure is simpler and easier to manufacture. Attached Figure Description

[0014] Figure 1 This is a three-dimensional view of the heating head of the electric heating tool according to a specific embodiment of this utility model; Figure 2 yes Figure 1 Cross-sectional view of the AA section of the heating element in a medium-sized electric heating tool; Figure 3 yes Figure 2 A partial view of section B; Figure 4 yes Figure 3 Cross-sectional view of an empty slot when no object is embedded in it; Figure 5 This is a three-dimensional view of the heating head of the electric heating tool according to a specific embodiment of this utility model; Figure 6 This is a front view of the heating head of the electric heating tool according to a specific embodiment of this utility model; Figure 7 yes Figure 6 The CC position section view; Figure 8 yes Figure 7 A partial view of section D in the middle; In the diagram, 1 is the heating head; 2 is the heating element; 3 is the groove; 4 is the heating wire; 5 is the metal wire; 6 is the bottom of the groove; 7 is the constriction; 8 is the wiring compartment; 9 is the connection part; 10 is the flow channel; and 11 is the chamfer. Detailed Implementation

[0015] Existing electric heating tools all include a heating head 1, which is used for heating and cleaning and scraping the inner wall of pipes. The heating head 1 typically includes a wiring compartment 8 and a heating element 2. The wiring compartment 8 is used to connect electrical wiring such as the heating wire 4 and sensors. The wiring compartment 8 also has a threaded connector for sealing connections to the power supply and other functional components of the electric heating tool. The heating element 2 is used to heat, scrape, and clean deposits on the inner wall of the pipe. Because the inner wall of the pipe is circular, the outer periphery of the heating element 2 usually has a cylindrical portion to better fit the inner wall. The heating head 1 also includes a connecting part 9 for connecting the wiring compartment 8 and the heating element 2. The connecting part 9 has a flow channel 10 for discharging debris cleaned or scraped during operation.

[0016] A specific embodiment of the heating wire inlay structure of the heating head of the electric heating tool proposed in this utility model is as follows: Figures 1-4 As shown, it includes a heating element 2 and a heating wire 4; in practical applications, the outer periphery of the heating element 2 includes at least two cylindrical segments. This embodiment exemplifies a practical application where the heating element 2 includes three cylindrical surfaces. The cylindrical surfaces are engraved with continuous grooves 3, the bottom 6 of the grooves 3 is arc-shaped, and the heating wire 4 is embedded in the grooves 3, with the heating wire 4 closely attached to the bottom 6 of the grooves.

[0017] like Figure 3 and Figure 4 As shown, the difference in this utility model lies in that the depth of the groove 3 is between 1.5 and 2.5 times the diameter of the heating wire 4; furthermore, after the heating wire 4 is embedded in the groove 3, there is still enough space for a metal wire 5 to be embedded on top of the heating wire 4. This metal wire 5 serves three purposes: first, it covers the heating wire 4 in the groove 3, protecting it from damage caused by external wear and impact; second, it improves the heat conduction effect of the heating wire 4 to the heating part 2. The metal wire 5 has good plastic deformation ability, and after being embedded, it fits tightly with the inner wall of the groove 3 and the upper part of the heating wire 4, covering and protecting the heating wire 4 on the one hand, and conducting the heat of the heating wire 4 to the heating part 2 through the contact between the metal wire and the groove wall. At the same time, a metal with a high thermal conductivity is used to improve the heat conduction efficiency; third, it prevents the heating wire 4 from coming out of the groove 3.

[0018] The inlaid heating wire structure proposed in this invention can also be used in applications where the outer periphery of the heating element of an electric heating tool is a non-cylindrical surface, including curved surfaces such as planes or spheres, for grooving and inlaying heating wires. However, in applications within oil pipelines, the heating element of commonly used electric heating tools is mostly cylindrical.

[0019] To facilitate the insertion of the metal wire 5 and prevent damage to the heating wire 4 and heating element 2, the metal wire 5 needs to have good plastic deformation ability to better fit the inner wall of the groove 3 and the upper part of the heating wire 4. In this embodiment, the hardness of the metal wire 5 is lower than that of the heating element 2 and the heating wire 4. In this embodiment, the heating element 2 is made of aluminum bronze, and the outer sheath of the heating wire 4 is stainless steel or stainless steel that has undergone special heat treatment. In practical applications, the metal wire 5 can be, but is not limited to, copper wire, aluminum wire, copper alloy wire, or aluminum alloy wire. In this embodiment, copper wire is used. Copper wire has better thermal conductivity, lower hardness, and better plasticity than the heating element 2 and the heating wire 4.

[0020] Because the heating wire 4 needs to be continuously laid out, and the same special-shaped milling cutter is used in the processing, the groove 3 has a continuous trajectory on the outer periphery of the heating part 2 and each part has the same groove cross-section.

[0021] In the specific technical solution proposed above, a new technical feature is further used: the top opening size of the groove 3 is smaller than the diameter of the heating wire 4. For example... Figure 3 As shown. Its purpose is to prevent the heating wire 4, which is embedded in the groove 3, from coming out of the groove 3. For example... Figure 4 As shown, in this embodiment, at the top of the groove 3, i.e., the groove top, which is the portion of the groove opening near the outer surface of the heating element 2 on both sides of the groove opening in the cross-section of the groove 3, there are narrowing slits 7. The narrowing slits 7 are a pair of symmetrical inward protrusions, making the size of the groove top opening smaller than the diameter of the heating wire 4. The size of the narrowing slits 7 (i.e., the size at the narrowest point) is between 85% and 99% of the diameter of the heating wire 4. Furthermore, these two protrusions each have a chamfered angle, facilitating the insertion of the heating wire 4 and the metal wire 5 into the groove 3. The heating wire 3 itself has a certain amount of elastic deformation, and the large size of the narrowing slits 7 is determined based on this elastic deformation. Therefore, during the insertion process into the groove 3, the heating wire 3 can contract through the chamfered narrowing slits 7 and then return to its original size. Because the metal wire 5 has lower hardness and better plasticity, it can be pressed into the groove 3 through the narrowing slits 7. Continued pressure after insertion into the groove 3 will cause the metal wire 5 to undergo plastic deformation, conforming to the inner wall of the groove 3 and the heating wire 4. This ensures that the metal wire 5 is not easily pulled out after being pressed into the groove 3.

[0022] Appendix Figure 3This diagram illustrates the application of the heating wire inlay structure of the heating head of this utility model's electric heating tool in Embodiment 1. The heating wire 4 and metal wire 5 are inlaid in the groove 3; only their relative positions are shown. In the diagram, the cross-sectional shape of the metal wire 5 is a complete ellipse. However, in actual application, because the metal wire 5 undergoes plastic deformation and is pressed into the groove 3, its cross-section will be deformed under pressure to better conform to the inner wall of the groove 3 and the shape of the heating wire 4 in contact, rather than a rounded circle or ellipse.

[0023] The above technical solution effectively overcomes the problem that in actual operation, the heating wire embedded in the grooves on the outer surface is easily worn, and in severe cases, the metal protective sheath is worn through, leading to a short circuit and damage to the internal circuitry of the heating wire. It also improves the heat transfer efficiency and heat utilization rate of the heating wire. Because before the metal wire 5 is covered, the side of the heating wire 4 facing the opening cannot contact the heating element 2, and the heat generated in this part cannot be transferred to the heating element 2.

[0024] Embodiment 2 of this utility model, as follows Figures 5-8 As shown, an embodiment of the heating wire inlay structure of the heating head of an electric heating tool is further illustrated, and a heating head employing this heating wire inlay structure is also proposed. This heating head includes a wiring compartment 8, a heating element 2, and a connecting element 9, as shown... Figure 5 and Figure 6 As shown, the heating part 2 of the heating head 1 is a cylinder, the thickness of the cylinder is greater than the depth of the groove 3, and more than two-thirds of the groove 3 is spirally distributed around the cylinder; the connecting part 9 consists of two parallel and identical columns, each of which is connected to the wiring compartment 8 and the heating part 2 at both ends, and the two columns are symmetrically distributed with respect to the axis of the cylinder; the two columns are separated from each other by at least 20 mm to form a flow channel 10 between the two ends of the cylinder of the heating part 2, which is used to discharge cleaning and / or scraping debris.

[0025] In this technical solution, because the trajectory of slot 3 is continuous and non-intersecting, it has one end, and the heating wire also needs a corresponding end. The heating wire 4, which needs to be embedded in slot 3, has a structure with one end leading out and the other end closed. The inner conductor of the closed end of the heating wire 4 is reliably electrically connected to the outer sheath of the heating wire 4 at that end, and the closed end is sealed against external moisture. The purpose of this technical solution is to ensure that the heating wire 4 and slot 3 form a non-intersecting spiral, while ensuring that both ends of the inner conductor of the heating wire 4 are electrically connected, thus forming a circuit. The heating wire 4 has a structure with one end leading out and the other end closed: the inner conductor of the closed end is welded to the outer sheath and sealed against moisture, and the leading end is led out through the inner conductor lead wire sealing cap and connected to the power supply line in the wiring compartment 8. The outer sheath is indirectly grounded through the heating part 2 (or connected to the other end of the power supply line), forming a complete power supply circuit. This embodiment uses a welding method, directly welding the inner conductor of the heating wire 4 to the outer sheath at the end, while also welding the opening of the outer sheath closed. This design ensures a reliable connection between the internal conductor of heating wire 4 and its outer sheath, while also guaranteeing a moisture seal at the end opening. Actual pressure testing proved that this welding method did not leak into the outer sheath of heating wire 4 under an external water pressure of 70 MPa, and heating wire 4 operated normally with normal power supply and heating.

[0026] To further enhance the cutting effect of the heating head, such as Figure 7 As shown, in this embodiment, a chamfer 11 with a chamfer of no more than 35° relative to the outer cylindrical surface is provided on the inner edge of the end of the cylinder facing away from the wiring compartment 8. The actual chamfer is 30°, so that the end forms a sharp outer edge.

[0027] Furthermore, to further improve the cutting performance of the end of the cylinder facing away from the wiring compartment 8, this end can be beveled into a needle-like shape, similar to the tip of a syringe needle. This means that when the end of the cylinder facing away from the wiring compartment 8 is beveled, the curve formed by the outer edge of this end is an ellipse that is not perpendicular to the cylinder axis. Without the bevel, this curve is a circle perpendicular to the cylinder axis. A further improvement is to add a chamfer 11 to the inner edge after the bevel. This will result in even better cutting performance.

[0028] Appendix Figure 8 This diagram illustrates the application of the heating wire inlay structure of the heating head of this utility model's electric heating tool in Embodiment 2. The heating wire 4 and metal wire 5 are inlaid in the groove 3; only their relative positions are shown. In the diagram, the cross-sectional shape of the metal wire 5 is a complete ellipse. However, in actual application, because the metal wire 5 undergoes plastic deformation and is pressed into the groove 3, its cross-section will deform under pressure to better conform to the inner wall of the groove 3 and the shape of the heating wire 4 in contact, rather than a rounded circle or ellipse.

[0029] The technical solution of this embodiment is simple to process and operate because the cylinder has a completely closed cylindrical surface, which allows for continuous grooving and wire inlay. At the same time, the use of a single-end inner conductor connected to the outer sheath and a sealing method makes it possible to use non-crossing spiral grooves 3 and inlay heating wires 4. This ultimately solves the problem that existing heating heads have complex grooving and inlaying paths for heating wires and require multiple sets of heating wires when the heating part is composed of two or more concentric cylindrical segments of the same radius.

Claims

1. A heating wire inlay structure for an electric heating head of an electric heating tool, comprising a heating element and a heating wire, wherein a groove is engraved on the outer peripheral surface of the heating element, the bottom of the groove is arc-shaped, the heating wire is inlaid in the groove, and the heating wire is in close contact with the bottom of the groove, characterized in that: The depth of the groove is between 1.5 and 2.5 times the diameter of the heating wire; Inside the groove, a metal wire is also embedded above the heating wire.

2. The heating wire inlay structure of the heating head of the electric heating tool as described in claim 1, characterized in that, The hardness of the metal wire is lower than that of the heating element and the heating wire.

3. The heating wire inlay structure of the heating head of the electric heating tool as described in claim 2, characterized in that, The metal wire includes copper wire, aluminum wire, or copper alloy wire or aluminum alloy wire.

4. The heating wire inlay structure of the heating head of the electric heating tool as described in claim 3, characterized in that, The metal wire includes copper wire.

5. The heating wire inlay structure of the heating head of the electric heating tool as described in any one of claims 1 to 4, characterized in that, The top of the groove is provided with a constriction, the size of which is between 85% and 99% of the diameter of the heating wire.

6. A heating head employing the heating wire inlay structure of the heating head of the electric heating tool according to claim 1, comprising a wiring compartment, a heating part, and a connecting part, characterized in that, The heating element of the heating head is a cylinder, the thickness of which is greater than the depth of the groove, and more than two-thirds of the groove is spirally distributed around the cylinder; the connecting part consists of two parallel and identical columns, each of which is connected to a wiring compartment and a heating element at its two ends, respectively, and the two columns are symmetrically distributed with respect to the axis of the cylinder; the two columns are separated from each other by at least 20mm to form a flow channel.

7. The heating head as described in claim 6, characterized in that, The inner conductor of one end of the heating wire embedded in the groove is reliably electrically connected to the outer sheath of the heating wire at that end, and the end is sealed to external moisture.

8. The heating head as described in claim 6, characterized in that, The inner edge of the end of the cylinder facing away from the wiring compartment has a chamfer of no more than 35°, so that the end forms a sharp outer edge.

9. The heating head as described in claim 8, characterized in that, The curve formed by the outer edge of the end is either a circle perpendicular to the axis of the cylinder or an ellipse not perpendicular to the axis.

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