A high temperature motor submersible cable connection device

Abstract

The invention discloses a high-temperature motor submersible cable connection device, which relates to the technical field of cable connection supporting facilities for oil production submersible electric pumps, including a lead-in cable, a power cable and a cold-pressed sleeve; the lead-in cable and the power cable respectively include three cable cores, each cable core includes a conductor, an insulation layer and a sheath layer from the inside to the outside, and a metal armor is also arranged on the outside of the three cable cores; the cold-pressed sleeve connects the conductor of the lead-in cable and the power cable into one; an insulating filling layer is arranged on the outside of the cold-pressed sleeve, the conductor and the insulation layer; an inner heat shrink sleeve is arranged on the outside of the insulating filling layer; an outer heat shrink tube is arranged on the outside of the inner heat shrink tube; a compensation clamp is arranged on both ends of the outer heat shrink tube, and a sealing ring is arranged between the compensation clamp and the outer heat shrink tube. The defect that the traditional cable sealing device is unreliable when operating at high temperature is solved, causing well fluid or gas to enter the cable sealing device and cause the cable to short-circuit and break down.

Description

Technical Field

[0001] The invention relates to the technical field of cable connection supporting facilities for oil exploitation submersible electric pumps, in particular to a high-temperature motor submersible cable connection device. Background Art

[0002] The high-temperature submersible electric pump is an efficient and reliable lifting equipment in the steam-assisted gravity drainage (SAGD) mining technology. The high-temperature submersible cable is the power transmission channel of the high-temperature submersible electric pump. The downhole part of the electric submersible pump unit and the high-temperature submersible cable work in a high-temperature environment of about 250°C. In order to facilitate the transportation of the electric submersible pump unit and improve the efficiency of on-site operations, during production and manufacturing, the high-temperature submersible motor in the high-temperature submersible electric pump unit is equipped with a lead cable of several tens of meters long. During the operation of the submersible electric pump downhole, the power cable needs to be connected to the lead cable. The current high-temperature submersible cable is a three-phase line with three cable cores. The core wire of each cable core is wrapped with multiple layers of insulation and sheath layers in turn, and the three cable cores are wrapped with stainless steel armor. When connecting the power cable to the lead cable, it is necessary to strip off a certain length of steel armor, and then use a special high-temperature cable joint sealing device. The cable joint sealing structure of a high-temperature submersible electric pump mentioned in patent number CN201510632986.9 is the structure currently used in domestic production. Although the mechanism adopts the double sealing technology of compensating seal and filling insulating oil, well fluid or gas enters the cable joint sealing mechanism during the production process, causing it to short-circuit and fail, resulting in equipment damage and further reduction in crude oil production; at the same time, three cable cores about 300mm-400mm long are exposed at the two ends of the high-temperature cable joint sealing mechanism, and no stainless steel armor is used for protection. Under the multiple effects of electrical stress, thermal stress and chemical substances, the insulation of the exposed cable core cracks.

[0003] Therefore, it is necessary to design a reliable and simple high-temperature cable connection mechanism, which not only ensures the insulation and sealing performance of the connection part, but also ensures that the cable at the connection has sufficiently high mechanical strength to resist the multiple effects of electrical stress, thermal stress and chemical substances, so that the high-temperature submersible pump can work normally. Summary of the invention

[0004] In order to solve the above technical problems, the present invention provides a high-temperature motor submersible cable connection device to overcome the problems of liquid and gas leakage in the existing high-temperature cable joint sealing mechanism, improve the insulation sealing performance of the high-temperature cable connection part, and ensure that the cable at the connection has sufficiently high mechanical strength to resist the multiple effects of electrical stress, thermal stress and chemical substances.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] The present invention provides a high-temperature motor submersible cable connection device, comprising a lead-in cable, a power cable and a cold-pressed sleeve; the lead-in cable and the power cable respectively comprise three cable cores, each of the cable cores comprises a conductor, an insulating layer and a sheath layer from the inside to the outside, and a metal armor is further arranged on the outside of the three cable cores; the cold-pressed sleeve connects the lead-in cable and the conductor of the power cable into one; an insulating filling layer is arranged on the outside of the cold-pressed sleeve, the conductor and the insulating layer; an inner-layer heat shrinkable sleeve is arranged on the outside of the insulating filling layer; an outer-layer heat shrinkable tube is arranged on the outside of the inner-layer heat shrinkable tube; a compensation clamp is arranged on each of the two ends of the outer-layer heat shrinkable tube, and a sealing ring is arranged between the compensation clamp and the outer-layer heat shrinkable tube.

[0007] Optionally, a reinforcement layer is provided on the outside of the outer heat shrinkable tube and the compensation clamp.

[0008] Optionally, the reinforcement layer is a woven glass ribbon or a polytetrafluoroethylene tape.

[0009] Optionally, the cold-pressed sleeve is a copper tube.

[0010] Optionally, the insulating filling layer is a polyimide film, or a pressure-sensitive adhesive tape, or a polytetrafluoroethylene tape.

[0011] Optionally, the inner heat shrink tube and the outer heat shrink tube are Teflon heat shrink tubes.

[0012] Optionally, the sealing ring is a fluororubber ring, and the compensation clamp is a constant pressure clamp with compensation capability.

[0013] Optionally, a protective cover is provided outside the outer heat shrink tube and the compensation clamp.

[0014] Optionally, a fixing card is respectively provided at both ends of the shield, and the fixing card is used to fix the shield to the metal armor.

[0015] Compared with the prior art, the present invention has achieved the following technical effects:

[0016] The high-temperature motor submersible cable connection device of the present invention has a compensating clamp at each end of the outer heat shrink tube, and a sealing ring is provided between the compensating clamp and the outer heat shrink tube, which can effectively prevent well fluid or gas from entering, thereby solving the problem that the traditional cable sealing device is unreliable when operating at high temperature, causing well fluid or gas to enter the cable sealing device and cause cable short circuit and breakdown.

[0017] The high-temperature motor submersible cable connection device of the present invention has a simple structure, can cover the exposed insulation, enhance the mechanical strength, and resist the damage caused by electrical stress, thermal stress and chemical substances. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a three-dimensional diagram of the connection of the high-temperature submersible oil cable of the present invention;

[0020] Figure 2 It is a schematic diagram of a high-temperature motor submersible cable connection device of the present invention;

[0021] Figure 3 It is a schematic diagram of the cable core connection between the lead-in cable and the power cable of the present invention;

[0022] Figure 4 It is a cross-sectional schematic diagram of a high-temperature motor submersible cable connection device of the present invention;

[0023] Description of reference numerals:

[0024] 1. High-temperature submersible motor, 2. Lead-in cable, 3. Power cable, 4. Cable core, 5. Cold-pressed casing, 6. Insulation filling layer, 7. Inner heat shrink casing, 8. Outer heat shrink casing, 9. Reinforcement layer, 10. Protective cover, 11. Sealing ring, 12. Compensation clamp, 13. Fixing card, 14. Metal armor, 341. Conductor, 342. Insulation layer, 343. Sheath layer. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] Embodiment 1:

[0027] like Figure 1As shown, this embodiment provides a high-temperature motor submersible cable connection device, including a lead-in cable 2, a power cable 3 and a cold-pressed sleeve 5; the lead-in cable 2 and the power cable 3 respectively include three cable cores 4, each of the cable cores 4 includes a conductor 341, an insulating layer 342 and a sheath layer 343 from the inside to the outside, and a metal armor 14 is also provided on the outside of the three cable cores 4; the cold-pressed sleeve 5 connects the lead-in cable 2 and the conductor 341 of the power cable 3 into one; an insulating filling layer 6 is provided on the outside of the cold-pressed sleeve 5, the conductor 341 and the insulating layer 342; an inner layer heat shrinkable sleeve 7 is provided on the outside of the insulating filling layer 6; an outer layer heat shrinkable tube is provided on the outside of the inner layer heat shrinkable tube; a compensation clamp 12 is provided at each end of the outer layer heat shrinkable tube, and a sealing ring 11 is provided between the compensation clamp 12 and the outer layer heat shrinkable tube.

[0028] In this specific embodiment, the length of the outer heat shrinkable tube is greater than the length of the inner heat shrinkable tube. A reinforcing layer 9 is provided on the outside of the outer heat shrinkable tube and the compensation clamp 12. The reinforcing layer 9 is a woven glass ribbon. The cold-pressed sleeve 5 is a copper tube. The insulating filling layer 6 is a polytetrafluoroethylene tape. The inner heat shrinkable tube and the outer heat shrinkable tube are Teflon heat shrinkable tubes. The sealing ring 11 is a fluororubber ring, the compensation clamp 12 is a constant pressure clamp with compensation capability, and the compensation clamp 12 has anti-corrosion capability. A shield 10 is provided on the outside of the outer heat shrinkable tube and the compensation clamp 12. A fixing card 13 is provided at each end of the shield 10, and the fixing card 13 is used to fix the shield 10 on the metal armor 14. The shield 10 is made of anti-corrosion material, and the inner cavity shape of the shield 10 is similar to that of the cable.

[0029] The high temperature motor submersible cable connection device in this embodiment is specifically implemented in the following manner:

[0030] First, the metal armor 14 at the connection end of the lead cable 2 and the power cable 3 is stripped off, and the conductor 341, the insulation layer 342 and the sheath layer 343 of the three cable cores 4 are stripped in sequence into a step-like shape from small to large;

[0031] The cold-pressed sleeve 5 connects the conductor 341 of the lead cable 2 and the power cable 3 into one, and the insulating filling layer 6 is wrapped around the insulating layer 342, the conductor 341 and the outer side of the cold-pressed sleeve 5 to increase the insulation capacity;

[0032] The inner heat shrinkable tube 7 is sleeved on the outside of the insulating filling layer 6, and the two ends of the outer heat shrinkable tube 8 are overlapped on the sheath, and the outer heat shrinkable tube 8 tightly covers the inner heat shrinkable tube 7;

[0033] The compensating clamp 12 with a built-in sealing ring 11 holds the outer heat shrinkable tube 8 and the sheath tightly to prevent the well fluid from entering the insulating layer 342 and the conductor 341 along the gap between the outer heat shrinkable tube and the sheath and causing the cable insulation to fail;

[0034] After the above operations are completed, a reinforcement layer 9 is wrapped around the outer surface of the sheath and the outer heat shrinkable tube 8 to further enhance the mechanical and electrical strength of the cable core 4. The wrapping interval is all the areas where the metal armor 14 is stripped off.

[0035] The two ends of the shield 10 are respectively overlapped on the outer surface of the metal armor 14 on the lead-in cable 2 and the power cable 3, and the shield 10 is firmly fixed on the cable by a fixing clip 13.

[0036] It should be noted that it is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiments, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, no matter from which point of view, the embodiments should be regarded as exemplary and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention, and any figure mark in the claims should not be regarded as limiting the claims involved.

[0037] The present specification uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A high-temperature motor submersible cable connection device, characterized in that: It comprises a connecting cable, a power cable and a cold-pressed sleeve; the connecting cable and the power cable respectively comprise three cable cores, each of which comprises a conductor, an insulating layer and a sheath layer from the inside to the outside, and a metal armor is further arranged on the outside of the three cable cores; the cold-pressed sleeve connects the connecting cable and the conductor of the power cable into one; an insulating filling layer is arranged on the outside of the cold-pressed sleeve, the conductor and the insulating layer; an inner heat shrink sleeve is arranged on the outside of the insulating filling layer; an outer heat shrink sleeve is arranged on the outside of the inner heat shrink sleeve; a compensation clamp is arranged on each of the two ends of the outer heat shrink sleeve, and a sealing ring is arranged between the compensation clamp and the outer heat shrink sleeve; A protective cover is arranged outside the outer heat shrinkable sleeve and the compensation clamp; The compensation clamp is a constant pressure clamp with compensation capability.

2. The high-temperature motor submersible cable connection device according to claim 1 is characterized in that: A reinforcement layer is arranged outside the outer heat shrinkable sleeve and the compensation clamp.

3. The high temperature motor submersible cable connection device according to claim 2 is characterized in that: The reinforcement layer is a woven glass ribbon or a polytetrafluoroethylene ribbon.

4. The high temperature motor submersible cable connection device according to claim 1, characterized in that: The cold-pressed casing is a copper tube.

5. The high temperature motor submersible cable connection device according to claim 1, characterized in that: The insulating filling layer is a polyimide film, a pressure-sensitive adhesive tape, or a polytetrafluoroethylene tape.

6. The high temperature motor submersible cable connection device according to claim 1, characterized in that: The inner heat shrinkable tube and the outer heat shrinkable tube are Teflon heat shrinkable tubes.

7. The high temperature motor submersible cable connection device according to claim 1, characterized in that: The sealing ring is a fluororubber ring.

8. The high temperature motor submersible cable connection device according to claim 1, characterized in that: A fixing card is respectively arranged at both ends of the shield, and the fixing card is used to fix the shield on the metal armor.

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