High-pressure-resistant anti-corrosion hydraulic oil pipe and process

Abstract

The high-pressure-resistant anti-corrosion hydraulic oil pipe comprises a pipe body, the two ends of the pipe body are connected with connecting joints respectively, each connecting joint comprises a connecting head A and a connecting head B, a butt joint groove is formed in one end of the connecting head A, and the end of the pipe body extends to the butt joint groove to be bonded; the preparation method comprises the following steps: S1, sequentially adding 40-50% of nitrile rubber powder, 10-15% of white graphite powder, 5-10% of an auxiliary agent and 20-30% of a solvent into an internal mixer at a time interval of about 3-4 minutes, uniformly stirring for 40-45 minutes, and curing for 15-20 hours to prepare a binding agent; the ethylene propylene rubber layer and the nitrile rubber layer both have good corrosion resistance, the corrosion resistance inside and outside the pipe body can be guaranteed, and the reinforced heat preservation layer is composed of the steel wire woven layer, the silica gel heat preservation filling layer and the polypropylene winding layer, so that the whole pipe body has good high pressure resistance; in addition, the pipe body and the connecting joint are subjected to a riveting bonding process, so that the connecting joint and the pipe body are firmly connected, and good sealing performance is achieved.

Description

Technical Field

[0001] The invention belongs to the technical field of hydraulic oil pipes, and in particular relates to a high-pressure resistant and corrosion-resistant hydraulic oil pipe and a process. Background Art

[0002] Hydraulic equipment, as a power transmission device, is widely used in excavators, loaders, rollers and other equipment. The hydraulic system of hydraulic equipment must have hydraulic oil pipes to transport hydraulic oil, which drives hydraulic motors, hydraulic cylinders and other hydraulic power units to do work. Existing rubber hydraulic oil pipes generally consist of a pipe body and a connecting joint;

[0003] The pipe body and connecting joints of the existing hydraulic oil pipe are generally bonded together by pressing, and the long-term sealing stability is limited, and leakage may occur. In addition, since the hydraulic oil pipe is subjected to a large pressure when in use, there are high requirements for the high-pressure resistance performance of the pipe body. For this reason, the current hydraulic oil pipe is generally formed by rubber and tensile fiber to form a composite structure of hydraulic oil pipe, and the pressure value of this high-pressure resistance is relatively limited. Therefore, the present invention proposes a high-pressure resistant and corrosion-resistant hydraulic oil pipe and a process. Summary of the invention

[0004] The purpose of the present invention is to provide a high-pressure resistant and corrosion-resistant hydraulic oil pipe and a process to solve the problems raised in the above background technology.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a high-pressure resistant and corrosion-resistant hydraulic oil pipe, comprising a pipe body, wherein both ends of the pipe body are respectively connected with connecting joints, each of the connecting joints comprises a connector A and a connector B, one end of the connector A is provided with a docking groove, the end of the pipe body extends to the docking groove for bonding, the connector A is also provided with a riveted seal for riveting the connector A and the pipe body, the connector B is screwed on the outside of the connector A through a thread, a retaining ring is provided on the connector A to prevent the connector B from slipping, silicone sealing rings are embedded on both sides of the retaining ring, and the pipe body comprises an EPDM rubber layer, a reinforced insulation layer and a nitrile rubber layer from the inside to the outside.

[0006] Preferably, the reinforced thermal insulation layer includes a silicone thermal insulation filling layer, a ring-shaped mesh steel wire braided layer arranged in the silicone thermal insulation filling layer, and a polypropylene winding layer wound around the outside of the silicone thermal insulation filling layer.

[0007] Preferably, the surface of the steel wire braided layer presents a uniformly distributed honeycomb structure.

[0008] Preferably, the riveted seal includes a raised clamping ring located in the docking groove, an annular groove opened on the outside of the connector A, and a riveted ring arranged in the annular groove, and the riveted ring is pressed against the tube body by high-temperature riveting.

[0009] Preferably, the inner front end of the connector B is provided with an internal thread, the connector A and the retaining ring are an integrated structure, and an anti-slip retreat groove is provided on the inner side of the connector B corresponding to the retaining ring.

[0010] A processing technology for a high-pressure resistant and corrosion-resistant hydraulic oil pipe, S1: 40%-50% of nitrile rubber powder, 10%-15% of white graphite powder, 5%-10% of an additive, and 20%-30% of a solvent are sequentially added to an internal mixer at a time interval of about 3-4 minutes, uniformly stirred for 40-45 minutes, and aged for 15-20 hours to obtain a binder;

[0011] S2: preheating the binder, the preheating temperature is controlled at 50°C-65°C; then, applying the binder to the surface of the EPDM rubber layer, the coating thickness is 0.2-0.3mm, to form a bonding layer 1;

[0012] S3: Use a winding machine to wind the stainless steel wire on the bonding layer 1 to form a steel wire braided layer;

[0013] S4: Then fill and cover the steel wire braided layer with a layer of silicone insulation filling layer with a thickness of 2-4mm;

[0014] S5: coating a layer of binder on the outer surface of the silicone thermal insulation filling layer to form a second bonding layer, and then winding polypropylene fibers on the outer surface of the silicone thermal insulation filling layer to form a polypropylene winding layer;

[0015] S6: Coating a layer of binder on the outer surface of the polypropylene winding layer, hot-melt wrapping the nitrile rubber on the outermost surface to form a nitrile rubber layer, and then heat-setting and cooling to obtain the tube body;

[0016] S7: First, sleeve the connector B onto the pipe body, then align the butt joint groove at one end of the connector A with the end of the pipe body and insert the connector A into the pipe body, then perform local heating and bonding, and at the same time, rivet the riveting ring so that the raised clamping ring is pressed into the pipe body;

[0017] S8: Cool the joints and then conduct a sealing test. If they pass the test, they can be packaged.

[0018] Preferably, in S7, the temperature of the heating bonding is 65° C.-75° C., and the time is 5-8 minutes.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: the pipe body designed by the present invention is a composite multilayer structure composed of an EPDM rubber layer, a reinforced insulation layer and a nitrile rubber layer from the inside to the outside, the EPDM rubber layer and the nitrile rubber layer both have good corrosion resistance, which can ensure the corrosion resistance of the inside and outside of the pipe body, and the reinforced insulation layer is composed of a steel wire braided layer, a silicone insulation filling layer and a polypropylene winding layer, so that the entire pipe body has good high-pressure resistance; in addition, the pipe body and the connecting joint are riveted and bonded, so that the connecting joint is firmly connected to the pipe body and has good sealing. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a front view structural schematic diagram of the present invention;

[0021] Figure 2 It is a schematic cross-sectional view of the connection between the connecting joint and the pipe body of the present invention;

[0022] Figure 3 It is a schematic diagram of the end cross-sectional structure of the pipe body of the present invention;

[0023] In the figure: 1. pipe body; 2. connector A; 3. connector B; 4. rivet ring; 5. docking groove; 6. raised clamping ring; 7. retaining ring; 8. silicone sealing ring; 11. nitrile rubber layer; 12. polypropylene winding layer; 13. silicone insulation filling layer; 14. steel wire braided layer; 15. ethylene propylene rubber layer. DETAILED DESCRIPTION

[0024] 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.

[0025] See also Figure 1 and Figure 3 The present invention provides a technical solution: a high-pressure resistant and corrosion-resistant hydraulic oil pipe, comprising a pipe body 1, with connecting joints respectively connected at both ends of the pipe body 1, each connecting joint comprising a connector A2 and a connector B3, a docking groove 5 is provided at one end of the connector A2, the end of the pipe body 1 extends to the docking groove 5 for bonding, a riveted seal for riveting the connector A2 and the pipe body 1 is also provided on the connector A2, a connector B3 is screwed on the outside of the connector A2 through a thread, a retaining ring 7 is provided on the connector A2 to prevent the connector B3 from slipping, a silicone sealing ring 8 is embedded on both sides of the retaining ring 7, and the pipe body 1 includes an EPDM rubber layer 15, a reinforced insulation layer and a nitrile rubber layer 11 from the inside to the outside.

[0026] In this embodiment, preferably, the reinforced insulation layer includes a silicone insulation filling layer 13 , an annular mesh steel wire braided layer 14 arranged in the silicone insulation filling layer 13 , and a polypropylene winding layer 12 wound around the outer side of the silicone insulation filling layer 13 .

[0027] In this embodiment, preferably, the surface of the steel wire braided layer 14 presents a honeycomb structure with uniform distribution.

[0028] In this embodiment, preferably, the riveted seal includes a raised clamping ring 6 located in the docking groove 5, an annular groove opened on the outside of the connector A2, and a riveted ring 4 arranged in the annular groove, and the riveted ring 4 is pressed against the tube body 1 by high-temperature riveting.

[0029] In this embodiment, preferably, the internal front end of the connector B3 is provided with an internal thread, the connector A2 and the retaining ring 7 are an integrated structure, and an anti-slip retreat groove is provided on the inner side of the connector B3 corresponding to the retaining ring 7.

[0030] A processing technology for a high-pressure resistant and corrosion-resistant hydraulic oil pipe, S1: 40%-50% of nitrile rubber powder, 10%-15% of white graphite powder, 5%-10% of an additive, and 20%-30% of a solvent are sequentially added to an internal mixer at a time interval of about 3-4 minutes, uniformly stirred for 40-45 minutes, and aged for 15-20 hours to obtain a binder;

[0031] S2: preheating the binder, the preheating temperature is controlled at 50°C-65°C; then, the binder is applied to the surface of the EPDM rubber layer 15, the coating thickness is 0.2-0.3mm, and a bonding layer 1 is formed;

[0032] S3: Using a winding machine to wind the stainless steel wire on the bonding layer 1 to form a steel wire braided layer 14;

[0033] S4: Fill and cover the steel wire braided layer 14 with a layer of silicone insulation filling layer 13, with a thickness of 2-4 mm;

[0034] S5: coating a layer of binder on the outer surface of the silicone thermal insulation filling layer 13 to form a second bonding layer, and then wrapping polypropylene fibers around the outer surface of the silicone thermal insulation filling layer 13 to form a polypropylene wrapping layer 12;

[0035] S6: Coating a layer of binder on the outer surface of the polypropylene winding layer 12, hot-melt wrapping the nitrile rubber on the outermost surface to form the nitrile rubber layer 11, and then heat setting and cooling to obtain the tube body 1;

[0036] S7: First, sleeve the connector B3 onto the tube body 1, then align the butt joint 5 at one end of the connector A2 with the end of the tube body 1 and insert and then perform local heating and bonding, and at the same time, riveting the riveting ring 4 so that the raised clamping ring 6 is pressed into the tube body 1;

[0037] S8: Cool the joints and then conduct a sealing test. If they pass the test, they can be packaged.

[0038] In this embodiment, preferably, in S7, the temperature of the heating bonding is 65° C.-75° C., and the time is 5-8 minutes.

[0039] Although the embodiments of the present invention have been shown and described, as detailed above, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A high-pressure resistant and corrosion-resistant hydraulic oil pipe, comprising a pipe body (1), wherein both ends of the pipe body (1) are respectively connected with connecting joints, characterized in that: Each of the connecting joints comprises a connector A (2) and a connector B (3), one end of the connector A (2) is provided with a docking groove (5), the end of the pipe body (1) extends to the docking groove (5) for bonding, the connector A (2) is also provided with a riveted seal for riveting the connector A (2) and the pipe body (1), the connector B (3) is screwed onto the outside of the connector A (2) through a thread, the connector A (2) is provided with a retaining ring (7) for preventing the connector B (3) from slipping off, both sides of the retaining ring (7) are embedded with a silicone sealing ring (8), and the pipe body (1) comprises, from the inside to the outside, an ethylene propylene rubber layer (15), a reinforced thermal insulation layer and a nitrile rubber layer (11).

2. The high-pressure resistant and corrosion-resistant hydraulic oil pipe according to claim 1, characterized in that: The reinforced thermal insulation layer comprises a silicone thermal insulation filling layer (13), a ring-shaped mesh steel wire braided layer (14) arranged inside the silicone thermal insulation filling layer (13), and a polypropylene winding layer (12) wound around the outside of the silicone thermal insulation filling layer (13).

3. The high-pressure resistant and corrosion-resistant hydraulic oil pipe according to claim 2, characterized in that: The surface of the steel wire braided layer (14) presents a uniformly distributed honeycomb structure.

4. The high-pressure resistant and corrosion-resistant hydraulic oil pipe according to claim 1, characterized in that: The riveting seal comprises a raised clamping ring (6) located in the docking groove (5), an annular groove formed on the outside of the connector A (2), and a riveting ring (4) disposed in the annular groove. The riveting ring (4) is pressed together with the tube body (1) by high-temperature riveting.

5. The high-pressure resistant and corrosion-resistant hydraulic oil pipe according to claim 1, characterized in that: The inner front end of the connector B (3) is provided with an internal thread, the connector A (2) and the retaining ring (7) are an integrated structure, and an anti-slip retraction groove is provided on the inner side of the connector B (3) corresponding to the retaining ring (7).

6. A process for processing a high pressure resistant and corrosion resistant hydraulic oil pipe according to any one of claims 1 to 5, characterized in that: S1: 40%-50% of nitrile rubber powder, 10%-15% of white graphite powder, 5%-10% of additives, and 20%-30% of solvent are sequentially added to an internal mixer at a time interval of about 3-4 minutes, stirred evenly for 40-45 minutes, and aged for 15-20 hours to obtain a binder; S2: preheating the binder, the preheating temperature is controlled at 50°C-65°C; then, coating the binder on the surface of the EPDM rubber layer (15) with a coating thickness of 0.2-0.3 mm to form a bonding layer 1; S3: using a winding machine to wind the stainless steel wire onto the bonding layer 1 to form a steel wire braided layer (14); S4: Fill and cover the steel wire braided layer (14) with a layer of silicone insulation filling layer (13) with a thickness of 2-4 mm; S5: coating a layer of binder on the outer surface of the silicone thermal insulation filling layer (13) to form a second bonding layer, and then wrapping polypropylene fibers around the outer surface of the silicone thermal insulation filling layer (13) and bonding them to form a polypropylene wrapping layer (12); S6: coating a layer of binder on the outer surface of the polypropylene winding layer (12), hot-melt-wrapping the nitrile rubber on the outermost surface to form the nitrile rubber layer (11), and then heat-setting and cooling to obtain the tube body (1); S7: First, the connector B (3) is sleeved onto the tube body (1), and then the butt joint groove (5) at one end of the connector A (2) is aligned with the end of the tube body (1), and then inserted and locally heated and bonded, and at the same time, the riveting ring (4) is riveted and pressed, so that the raised clamping ring (6) is pressed into the tube body (1); S8: Cool the joints and then conduct a sealing test. If they pass the test, they can be packaged.

7. The processing technology of the high-pressure resistant and corrosion-resistant hydraulic oil pipe according to claim 1 is characterized in that: In S7, the temperature of the heating bonding is 65° C.-75° C., and the time is 5-8 minutes.

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