Nitrile rubber sheath submersible cable

Abstract

The invention relates to the technical field of submersible cables used in oil and gas production, in particular to a nitrile rubber sheath submersible cable, and aims to solve the problems of poor mechanical properties such as tensile strength and elongation at break in the prior art. The invention provides an oil-submersible cable with a nitrile rubber sheath. The oil-submersible cable with the nitrile rubber sheath comprises a conductor, an insulating layer, a sheath, a wrapping layer and an armor layer, the conductor, the insulating layer, the sheath, the wrapping layer and the armor layer are sequentially connected from inside to outside, the insulating layer is wrapped outside the conductor, the sheath is wrapped outside the insulating layer, the wrapping layer is wrapped outside the sheath, and the armor layer is wrapped outside the wrapping layer; wherein the sheath comprises the following components in parts by weight: 50-60 parts of butadiene-acrylonitrile rubber; 6-12 parts of a softening plasticizer; 1.3 to 3 parts of an anti-aging agent; 18 to 48 parts of a reinforcing agent; 2 to 7.5 parts of an accelerant; and 0.5 to 1 part of a vulcanizing agent. The nitrile rubber sheath submersible cable provided by the invention can adapt to a complex oil well environment, and has good tensile strength, elongation at break and other mechanical properties.

Description

Technical Field

[0001] The invention relates to the technical field of submersible cables used in oil and gas production, in particular to a nitrile rubber sheathed submersible cable. Background Art

[0002] The upper end of the submersible cable is connected to the ground control cabinet, and the lower end is connected to the submersible motor. It transmits electricity to the submersible motor underground and is one of the important products of oil extraction. Submersible cables work in complex environments of oil wells at a depth of several thousand meters underground for a long time. They are accompanied by high temperature, high pressure, and high corrosion for a long time. The various performance requirements of the sheath are much more stringent than those of ordinary power cables. Among them, users have higher and higher requirements for the mechanical properties of the sheath. The formulation and processing of existing submersible cables cannot meet the increasingly enhanced requirements of tensile strength, elongation at break and other mechanical properties. Further research, design and invention are needed to provide a nitrile rubber sheathed submersible cable with excellent tensile strength and elongation at break to adapt to the increasingly complex oil well environment and meet the use requirements. Summary of the invention

[0003] The object of the present invention is to provide a nitrile rubber sheathed submersible cable to solve the problem of poor mechanical properties such as tensile strength and elongation at break in the prior art.

[0004] In order to solve the above technical problems, the technical solution provided by the present invention is:

[0005] The present invention provides a nitrile rubber sheathed submersible cable, which comprises: a conductor, an insulating layer, a sheath, a wrapping layer and an armor layer;

[0006] The conductor, the insulating layer, the sheath, the wrapping layer and the armor layer are connected in sequence from the inside to the outside, the insulating layer is wrapped around the outside of the conductor, the sheath is wrapped around the outside of the insulating layer, the wrapping layer is wrapped around the outside of the sheath, and the armor layer is wrapped around the outside of the wrapping layer;

[0007] Wherein, the sheath comprises the following components in weight ratio:

[0008] Nitrile rubber: 50-60 parts;

[0009] Softening plasticizer: 6-12 parts;

[0010] Anti-aging agent: 1.3-3 parts;

[0011] Reinforcing agent: 18-48 parts;

[0012] Accelerator: 2-7.5 parts;

[0013] Vulcanizing agent: 0.5-1 part.

[0014] Furthermore,

[0015] The softening plasticizer is one or more of coumarone, stearic acid and TCP.

[0016] Furthermore,

[0017] The antioxidant is one or more of antioxidant H, antioxidant RD, and antioxidant D.

[0018] Furthermore,

[0019] The reinforcing agent is one or more of zinc oxide, calcined kaolin, white carbon black and talc.

[0020] Furthermore,

[0021] The accelerator is one or more of DM and TMTD;

[0022] The vulcanizing agent is sulfur.

[0023] Furthermore,

[0024] The softening plasticizer contains 4 to 7 parts of coumarone, 1 to 3 parts of stearic acid and 1 to 2 parts of TCP.

[0025] Furthermore,

[0026] The antioxidant H in the antioxidant is 0.5-1 part, the antioxidant RD is 0.3-1 part, and the antioxidant D is 0.5-1 part.

[0027] Furthermore,

[0028] The reinforcing agent contains 1 to 3 parts of zinc oxide, 5 to 15 parts of calcined kaolin, 12 to 30 parts of white carbon black and 5 to 15 parts of talc.

[0029] Furthermore,

[0030] The DM in the accelerator is 1 to 5 parts, and the TMTD is 1 to 2.5 parts.

[0031] Furthermore,

[0032] The conductor is an electrical round copper wire or a tinned round copper wire;

[0033] The insulating layer comprises polypropylene or polyimide-F46 composite film and EPDM rubber;

[0034] The wrapping layer comprises an inner layer and an outer layer, wherein the inner layer is a polytetrafluoroethylene stretch film or a polyester film, and the outer layer is a polyester or nylon;

[0035] The armor layer is a galvanized steel strip, a stainless steel strip, or a monel steel strip.

[0036] Based on the above technical solutions, the technical effects that can be achieved by the present invention are:

[0037] The nitrile rubber sheath formula in the nitrile rubber sheathed submersible cable provided by the present invention adopts a scientific formula design of domestic nitrile rubber raw rubber and a variety of cable-specific auxiliary materials, improves the mechanical properties of the cable sheath by adding a filling ultrafine reinforcing agent and a multi-component accelerator, improves the aging and oil resistance of the cable sheath by selecting and proportioning materials such as an antioxidant and a vulcanizing agent, and ensures the processing performance of the cable by selecting and proportioning materials such as a vulcanizing agent and a plasticizer, thereby solving the problem of poor mechanical properties such as tensile strength and elongation at break in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0039] Figure 1 A schematic structural diagram of a nitrile rubber sheathed submersible cable provided in an embodiment of the present invention.

[0040] Icon: 1-conductor; 2-insulation layer; 3-sheath; 4-wrapping layer; 5-armor layer. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0042] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. 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.

[0043] Some embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments can be combined with each other.

[0044] The invention provides a nitrile rubber sheathed submersible cable, which comprises: a conductor 1, an insulating layer 2, a sheath 3, a wrapping layer 4 and an armor layer 5; the conductor 1, the insulating layer 2, the sheath 3, the wrapping layer 4 and the armor layer 5 are connected in sequence from the inside to the outside, the insulating layer 2 is wrapped around the outside of the conductor 1, the sheath 3 is wrapped around the outside of the insulating layer 2, the wrapping layer 4 is wrapped around the outside of the sheath 3, and the armor layer 5 is wrapped around the outside of the wrapping layer 4; wherein the sheath 3 comprises the following components in weight ratio: nitrile rubber: 50-60 parts; softening plasticizer: 6-12 parts; antioxidant: 1.3-3 parts; reinforcing agent: 18-48 parts; accelerator: 2-7.5 parts; vulcanizer: 0.5-1 part.

[0045] The formula of the nitrile rubber sheath 3 in the nitrile rubber sheathed submersible cable provided by the present invention adopts a scientific formula design of domestic nitrile rubber raw rubber and a variety of cable-specific auxiliary materials, improves the mechanical properties of the cable sheath 3 by adding a filling ultrafine reinforcing agent and a multi-component accelerator, improves the aging and oil resistance of the cable sheath 3 by selecting and proportioning materials such as antioxidants and vulcanizers, ensures the processing performance of the cable by selecting and proportioning materials such as peroxide-assisted vulcanizers and plasticizers, and solves the problem of poor mechanical properties such as tensile strength and elongation at break in the prior art.

[0046] The following combination Figure 1 The structure and shape of the nitrile rubber sheathed submersible cable provided in this embodiment are described in detail.

[0047] like Figure 1 As shown, the nitrile rubber sheathed submersible cable provided in this embodiment includes: a conductor 1, an insulating layer 2, a sheath 3, a wrapping layer 4 and an armor layer 5; the conductor 1, the insulating layer 2, the sheath 3, the wrapping layer 4 and the armor layer 5 are connected in sequence from the inside to the outside. The conductor 1 is an electrical round copper wire or a tinned round copper wire, the insulating layer 2 is a combined insulation of polypropylene or polyimide-F46 composite film and EPDM rubber, the sheath 3 is a nitrile rubber or a combined sheath 3 of lead and nitrile rubber, the wrapping layer 4 is a combination of stretched polytetrafluoroethylene or polyester film (inner layer) and polyester or nylon (outer layer), and the armor layer 5 is a galvanized steel strip or a stainless steel strip or a monel steel strip. Among them, the conductor 1 is round, the core of the insulating layer 2 is round, the core of the sheath 3 is round, and the core of the wrapping layer 4 is round; the armor layer 5 is firmly armored with steel strips, and the armor layer 5 can be wrapped with a number of conductors 1 arranged side by side, refer to Figure 1 Three conductors 1 arranged side by side may be arranged inside the armor layer 5 to form a flat integral structure, wherein the conductor 1 is wrapped with an insulating layer 2, the insulating layer 2 is wrapped with a sheath 3, the sheath 3 is wrapped with a wrapping layer 4, and the wrapping layer 4 is wrapped with an armor layer 5.

[0048] The preparation method of the nitrile rubber sheathed submersible cable provided in this embodiment is as follows:

[0049] a. A layer of polypropylene insulation with a thickness of 2.3 mm or a combined insulation of polyimide-F46 composite film and EPDM rubber is produced on the surface of conductor 1.

[0050] b. Use special cable rubber extrusion equipment, a suspension controller and a water vapor balance device. Under the action of steam vulcanization at a pipeline pressure of 1MPa to 2MPa, design a special extrusion die with a die angle difference of 42° and a die distance of 8mm to 10mm to produce a 1.5mm thick nitrile rubber sheath 3 or a combined sheath 3 of lead and nitrile rubber on the surface of the insulating core.

[0051] c. The outer sheath layer is wrapped with polyester or nylon tape, and the overlap rate is ≥50%.

[0052] d. The three wire cores are arranged in parallel and the outer surface is wrapped with a Z-shaped or S-shaped steel tape interlocking armor layer 5.

[0053] e. The sheath 3 comprises the following components in weight ratio:

[0054] Nitrile rubber: 50-60 parts, softening plasticizer: 6-12 parts, antioxidant: 1.3-3 parts, reinforcing agent: 18-48 parts, accelerator: 2-7.5 parts, vulcanizing agent: 0.5-1 part.

[0055] The softening plasticizer is one or more of coumarone, stearic acid and TCP.

[0056] The antioxidant is one or more of antioxidant H, antioxidant RD, and antioxidant D.

[0057] The reinforcing agent is one or more of zinc oxide, calcined kaolin, white carbon black and talc.

[0058] The accelerator is one or more of DM and TMTD.

[0059] The vulcanizing agent is sulfur.

[0060] Preferably, the softening plasticizer includes 4-7 parts of coumarone, 1-3 parts of stearic acid, and 1-2 parts of TCP. The antioxidant H includes 0.5-1 parts of antioxidant RD, 0.3-1 parts of antioxidant D, and 0.5-1 parts of antioxidant. The reinforcing agent includes 1-3 parts of zinc oxide, 5-15 parts of calcined kaolin, 12-30 parts of white carbon, and 5-15 parts of talc. The accelerator includes 1-5 parts of DM and 1-2.5 parts of TMTD.

[0061] The following specific examples are given to illustrate the mixing components of the nitrile rubber sheath 3.

[0062] Nitrile rubber sheath 3 mixing component example 1

[0063] Nitrile rubber: 55 parts; Coumarone: 5 parts; Stearic acid: 2 parts; TCP: 1.6 parts; Antioxidant H: 2.2 parts; Calcined kaolin: 48 parts; TMTD: 5 parts; Sulfur: 1 part.

[0064] Nitrile rubber sheath 3 mixing component example 2

[0065] Nitrile rubber: 55 parts; Coumarone: 5 parts; Stearic acid 2 parts; TCP: 1.6 parts; Antioxidant H: 0.8 parts; Antioxidant RD: 0.5 parts; Antioxidant D: 0.7 parts; Zinc oxide: 1.8 parts; Calcined kaolin: 10 parts; White carbon black: 22 parts; Talc: 12 parts; DM: 3 parts; TMTD: 2.2 parts; Sulfur: 0.7 parts.

[0066] The technical indicators of the products prepared using the components of Example 1 and Example 2 were evaluated, and the results are shown in Table 1.

[0067] Table 1:

[0068] The existing commercially available submersible cable (model QYPN3-3×20 / 90) was used as comparative example 1 to conduct technical index evaluation. The results are shown in Table 2.

[0069] By adding antioxidant, reinforcing agent, accelerator, adjusting the proportion of the compound components and testing, and by comparing the compound components after production, the compound component design of Example 2 has significantly improved mechanical properties such as tensile strength and elongation at break.

[0070] Table 2:

[0071] The nitrile rubber sheathed submersible cable provided in this embodiment improves the mixing and processing performance of rubber, and forms a set of mixing and continuous production technology suitable for domestic rubber. Continuous extrusion and high-pressure saturated steam vulcanization technology are adopted, a special extrusion die is designed, the die angle difference and the die distance are adjusted, and the length of the bearing diameter area is changed; a suspension controller and a water vapor balance device are adopted to form a set of production technology suitable for continuous extrusion and steam vulcanization of domestic rubber.

[0072] This embodiment provides a nitrile rubber sheathed cable through research on nitrile rubber cable materials, component research and design, and production technology research and implementation. The cable can adapt to complex oil well environments, has good tensile strength, elongation at break and other mechanical properties, and realizes domestic production and substitution.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A nitrile rubber sheathed submersible cable, It is characterized in that The nitrile rubber sheathed submersible cable comprises: a conductor (1), an insulating layer (2), a sheath (3), a wrapping layer (4) and an armor layer (5); The conductor (1), the insulating layer (2), the sheath (3), the wrapping layer (4) and the armor layer (5) are connected in sequence from the inside to the outside, the insulating layer (2) is wrapped around the outside of the conductor (1), the sheath (3) is wrapped around the outside of the insulating layer (2), the wrapping layer (4) is wrapped around the outside of the sheath (3), and the armor layer (5) is wrapped around the outside of the wrapping layer (4); Wherein, the sheath (3) comprises the following components in weight ratio: Nitrile rubber: 50-60 parts; Softening plasticizer: 6-12 parts; Anti-aging agent: 1.3-3 parts; Reinforcing agent: 18-48 parts; Accelerator: 2-7.5 parts; Vulcanizing agent: 0.5-1 part.

2. The nitrile rubber sheathed submersible cable according to claim 1, It is characterized in that The softening plasticizer is one or more of coumarone, stearic acid and TCP.

3. The nitrile rubber sheathed submersible cable according to claim 1, It is characterized in that The antioxidant is one or more of antioxidant H, antioxidant RD, and antioxidant D.

4. The nitrile rubber sheathed submersible cable according to claim 1, It is characterized in that The reinforcing agent is one or more of zinc oxide, calcined kaolin, white carbon black and talc.

5. The nitrile rubber sheathed submersible cable according to claim 1, It is characterized in that The accelerator is one or more of DM and TMTD; The vulcanizing agent is sulfur.

6. The nitrile rubber sheathed submersible cable according to claim 1, It is characterized in that The softening plasticizer contains 4 to 7 parts of coumarone, 1 to 3 parts of stearic acid and 1 to 2 parts of TCP.

7. The nitrile rubber sheathed submersible cable according to claim 1, It is characterized in that The antioxidant H in the antioxidant is 0.5-1 part, the antioxidant RD is 0.3-1 part, and the antioxidant D is 0.5-1 part.

8. The nitrile rubber sheathed submersible cable according to claim 1, It is characterized in that The reinforcing agent contains 1 to 3 parts of zinc oxide, 5 to 15 parts of calcined kaolin, 12 to 30 parts of white carbon black and 5 to 15 parts of talc.

9. The nitrile rubber sheathed submersible cable according to claim 1, It is characterized in that The DM in the accelerator is 1 to 5 parts, and the TMTD is 1 to 2.5 parts.

10. The nitrile rubber sheathed submersible cable according to claim 1, It is characterized in that The conductor (1) is an electrical round copper wire or a tinned round copper wire; The insulating layer (2) is made of raw materials including polypropylene or polyimide-F46 composite film and EPDM rubber; The wrapping layer (4) comprises an inner layer and an outer layer, wherein the inner layer is a stretched polytetrafluoroethylene or polyester film, and the outer layer is a polyester or nylon; The armor layer (5) is a galvanized steel strip, a stainless steel strip, or a monel steel strip.

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