A polytetrafluoroethylene corrugated hose assembly with a fluorosilicone rubber seal

Abstract

The application belongs to the technical field of fluid transmission pipeline, and provides a polytetrafluoroethylene corrugated hose assembly with a fluorosilicone rubber sealing ring, which comprises a hose body and a metal joint; the two ends of the hose body are provided with the metal joint, the metal joint is sleeved on the hose body, and a fluorosilicone rubber sealing ring is arranged between the metal joint and the hose body; the metal joint is used for compressing the fluorosilicone rubber sealing ring during assembly, and plays a sealing role; the application has compact structure, excellent sealing performance and long service life, solves the high-temperature leakage problem of the polytetrafluoroethylene corrugated hose assembly, can be widely applied to the field of aerospace, and realizes self-controllable core key parts.

Description

Technical Field

[0001] This invention belongs to the field of fluid transmission pipeline technology, specifically relating to a polytetrafluoroethylene corrugated hose assembly with a fluorosilicone rubber sealing ring. Background Technology

[0002] Polytetrafluoroethylene (PTFE) corrugated hose assemblies, due to their excellent chemical stability, wide temperature range (-60℃ to +260℃), low coefficient of friction, and aging resistance, have become core components in modern aerospace vehicles and aircraft engine hydraulic, fuel, and lubricating oil systems for transporting critical media (such as hydraulic oil, fuel, and lubricating oil). In confined spaces and harsh environments such as engine compartments, PTFE corrugated hose assemblies can replace PTFE straight pipes and rigid pipelines, effectively compensating for displacement and stress caused by thermal expansion and contraction, vibration, and installation deviations, significantly improving system reliability. However, in practical applications, aircraft engines operate under extreme conditions, including high-frequency severe vibration, pressure pulses, and cyclic temperature changes. Traditional designs are prone to fatigue failure and media leakage under high-temperature pulse pressure impacts. For the aviation industry, even a small leak can lead to system performance degradation and pose a significant safety hazard. The weakest point of a PTFE corrugated hose assembly is often the seal between the PTFE corrugated inner tube and the metal fitting. Therefore, developing a polytetrafluoroethylene corrugated hose joint sealing structure that can withstand extreme dynamic environments, ensures sealing reliability, and has a long service life has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a polytetrafluoroethylene corrugated hose assembly with a fluorosilicone rubber sealing ring, thereby solving the problems in the prior art. The technical solution adopted by this invention is as follows: A polytetrafluoroethylene corrugated hose assembly with a fluorosilicone rubber seal, comprising a hose body and a metal fitting. Metal connectors are installed at both ends of the hose body. The metal connectors are sleeved on the hose body, and a fluorosilicone rubber sealing ring is provided between the metal connectors and the hose body. The metal connectors are used to compress the fluorosilicone rubber sealing ring during assembly to achieve a sealing effect.

[0004] Furthermore, the hose body includes, from the inside out, a polytetrafluoroethylene corrugated inner tube, a fiberglass cloth layer, a stainless steel wire reinforcement layer, and a fire-resistant rubber layer.

[0005] Furthermore, the metal joint includes a core rod, a sleeve, and a nut; One end of the core rod is inserted into the corrugated inner tube of polytetrafluoroethylene, and the other end of the core rod is fitted with the nut; the sleeve is fitted onto the corrugated inner tube of polytetrafluoroethylene, the outer surface of the core rod is provided with an anti-pull-out groove and a sealing groove, and the inner side of the sleeve is provided with a protrusion that engages with the anti-pull-out groove.

[0006] Furthermore, multiple sealing grooves are provided on the outer surface of the core rod, and at least two of the sealing grooves are fitted with fluorosilicone rubber sealing rings.

[0007] Furthermore, the polytetrafluoroethylene corrugated inner tube is a corrugated tube with a conductive carbon black layer on its inner wall.

[0008] Furthermore, the glass fiber cloth layer is glass fiber impregnated cloth.

[0009] Furthermore, the stainless steel wire reinforcement layer is made by stranding multiple stainless steel wires together.

[0010] Furthermore, the main adhesive material of the fire-retardant rubber layer is silicone rubber.

[0011] This invention offers the following advantages: By employing a sealing structure that combines a fluorosilicone rubber sealing ring with a PTFE corrugated inner tube, the reliability and service life of the hose assembly under extreme operating conditions are significantly improved. Compared with existing technologies, the fluorosilicone rubber sealing ring maintains stable compression resilience over a long period under high temperature (-60℃ to 200℃) and alternating pulse pressure conditions, effectively preventing media leakage due to insufficient sealing material performance. The anti-pull-out structure and multiple sealing grooves on the core rod enhance the mechanical engagement and sealing uniformity of the joint under vibration and pressure, further improving the fatigue resistance and anti-pull-out capability of the overall structure. Simultaneously, the composite tube body provides heat insulation, reinforcement, and fire resistance, making the hose assembly particularly suitable for harsh environments such as aero-engines, significantly improving the safety and reliability of system operation. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the overall structure; Figure 2 This is a magnified view of a local structure; In the diagram: 1. Conductive carbon black layer; 2. Polytetrafluoroethylene inner tube; 3. Fiberglass cloth layer; 4. Stainless steel wire reinforcement layer; 5. Fireproof rubber layer; 6. Anti-pull-out groove; 7. Sealing groove; 8. Fluorosilicone rubber sealing ring; 9. Core rod; 10. Sleeve; 11. Nut. Detailed Implementation

[0013] The following will be described in conjunction with embodiments of the present invention. Figure 1-2The technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Unless otherwise specified, the technical means used in the embodiments are conventional means well known to those skilled in the art.

[0014] like Figures 1-2 The present invention provides a polytetrafluoroethylene corrugated hose assembly with a fluorosilicone rubber sealing ring, comprising a hose body and a metal connector. Metal connectors are installed at both ends of the hose body. The metal connectors are sleeved on the hose body, and a fluorosilicone rubber sealing ring 8 is provided between the metal connectors and the hose body. The metal connectors are used to compress the fluorosilicone rubber sealing ring 8 during assembly to achieve a sealing effect.

[0015] Furthermore, the hose body includes, from the inside out, a polytetrafluoroethylene corrugated inner tube 2, a fiberglass cloth layer 3, a stainless steel wire reinforcing layer 4, and a fireproof rubber layer 5.

[0016] The fiberglass cloth layer 3 is mainly used for heat insulation, insulation, and protection of the internal PTFE corrugated inner tube 2. The stainless steel wire reinforcement layer 4 is wrapped around the fiberglass cloth layer 3 by weaving or winding to withstand the internal pressure of the pipeline and provide compressive and tensile strength; the outermost fireproof rubber layer 5 provides physical protection, fireproofing, and further vibration isolation.

[0017] Furthermore, the metal joint includes a core rod 9, a sleeve 10, and a nut 11; the metal joint is preferably made of corrosion-resistant austenitic stainless steel to ensure the strength and durability of the overall structure under harsh environmental conditions.

[0018] One end of the core rod 9 is inserted into the polytetrafluoroethylene corrugated inner tube 2, and the other end of the core rod 9 is fitted with the nut 11; the sleeve 10 is fitted onto the polytetrafluoroethylene corrugated inner tube 2, the outer surface of the core rod 9 is provided with an anti-pull-out groove 6 and a sealing groove 7, and the inner side of the sleeve 10 is provided with a protrusion that engages with the anti-pull-out groove 6.

[0019] The anti-pull-out groove 6 is located at the front end of the core rod 9 inserted into the polytetrafluoroethylene corrugated inner tube 2. The anti-pull-out groove 6 and the protrusion form a mechanical engagement to prevent the hose from coming loose from the joint under pressure or vibration.

[0020] Furthermore, multiple sealing grooves 7 are provided on the outer surface of the core rod 9, and at least two of the sealing grooves 7 are fitted with fluorosilicone rubber sealing rings 8.

[0021] Multiple sealing grooves 7 have varying spacing and depths, and include at least two independent ones for assembling fluorosilicone rubber sealing rings 8. The interface shape of the sealing grooves 7 matches the interface of the fluorosilicone rubber sealing rings 8, and their groove depth and width are precisely designed to ensure that after the sleeve 10 is crimped, the fluorosilicone rubber sealing rings 8 can be accurately compressed to a preset compression ratio, forming a stable and uniform radial sealing pressure between the inner wall of the corrugated inner tube and the sealing grooves 7.

[0022] First, install the fluorosilicone rubber sealing ring 8 into the sealing groove 7 on the core rod 9. During assembly, first place the sleeve 10 on the outside of the PTFE corrugated inner tube 2, then insert the core rod 9 through the nut 11 into the end of the PTFE corrugated inner tube 2. After assembly, apply radial pressure to the sleeve 10 using a crimping device, forcing the PTFE corrugated inner tube 2 to undergo radial contraction deformation, thereby tightly compressing the fluorosilicone rubber sealing ring 8 between the core rod 9 and the PTFE corrugated inner tube 2, forming a reliable radial static sealing interface.

[0023] Furthermore, the polytetrafluoroethylene corrugated inner tube 2 is a corrugated tube, and its inner wall is provided with a conductive carbon black layer 1.

[0024] The PTFE corrugated inner tube 2 forms a fluid channel and possesses excellent thermal stability (long-term operating temperature -60℃ to 260℃), fatigue resistance, and chemical corrosion resistance. It is formed by co-extruding a conductive carbon black layer 1 and a PTFE resin mixture with a PTFE tube preform using a double-layer co-extrusion technique to create a straight PTFE inner tube, which is then spirally extruded using a special die to form the PTFE corrugated inner tube 2. The corrugated shape of the PTFE corrugated inner tube 2 has crests and troughs, allowing it to mate with the fluorosilicone rubber sealing ring 8. After crimping, the crests and troughs of the PTFE corrugated inner tube 2 tend to straighten.

[0025] Furthermore, the glass fiber cloth layer 3 is a straight-cut 45° obliquely wound glass fiber impregnated cloth.

[0026] Fiberglass impregnated cloth is cut at a 45° angle and coated with a special adhesive. It is then tightly wrapped around the outer crests and troughs of the PTFE corrugated inner tube 2 with a half-overlap. Its main functions are heat insulation, electrical insulation, and cushioning, protecting the inner tube from external heat sources and mechanical damage. The fiberglass impregnated cloth is made by coating fiberglass cloth with fluorosilicone rubber using a coating machine.

[0027] Furthermore, the stainless steel wire reinforcement layer 4 is made of multiple strands of stainless steel wire woven together at a 54°44′ angle onto the pipe body. This layer is the core reinforcement structure that withstands the internal working pressure and axial tensile force of the pipeline, providing excellent compressive, tensile, and pulse fatigue resistance.

[0028] Furthermore, the main adhesive material of the fire-retardant rubber layer 5 is silicone rubber. The fire-retardant silicone rubber is laminated onto the stainless steel wire reinforcing layer 4 using a molding process. This layer primarily provides physical protection, fire resistance, further vibration isolation, and aesthetic appeal.

[0029] During installation, the sleeve 10 is fitted onto the PTFE corrugated inner tube 2; the core rod 9, fitted with the fluorosilicone rubber sealing ring 8, passes through the nut 11 and continues to be inserted into the PTFE corrugated inner tube 2. A certain clamping force is applied radially by the clamping equipment to tightly press the sleeve 10, the tube body and the core rod 9 together to form a reliable and durable hose assembly.

[0030] The above embodiments are merely descriptions of preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Any modifications, alterations, alterations, or substitutions made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A polytetrafluoroethylene corrugated hose assembly with a fluorosilicone rubber sealing ring, characterized in that, Includes the hose body and metal fittings; Metal connectors are installed at both ends of the hose body. The metal connectors are sleeved on the hose body, and a fluorosilicone rubber sealing ring (8) is provided between the metal connectors and the hose body. The metal connectors are used to compress the fluorosilicone rubber sealing ring (8) during assembly to achieve a sealing effect.

2. The polytetrafluoroethylene corrugated hose assembly with a fluorosilicone rubber sealing ring according to claim 1, characterized in that, The hose body includes, from the inside out, a polytetrafluoroethylene corrugated inner tube (2), a fiberglass cloth layer (3), a stainless steel wire reinforcement layer (4), and a fireproof rubber layer (5).

3. The polytetrafluoroethylene corrugated hose assembly with a fluorosilicone rubber sealing ring according to claim 1, characterized in that, The metal connector includes a core rod (9), a sleeve (10), and a nut (11). One end of the core rod (9) is inserted into the polytetrafluoroethylene corrugated inner tube (2), and the other end of the core rod (9) is fitted with the nut (11); the sleeve (10) is fitted onto the polytetrafluoroethylene corrugated inner tube (2), the outer surface of the core rod (9) is provided with an anti-pull-out groove (6) and a sealing groove (7), and the inner side of the sleeve (10) is provided with a protrusion that engages with the anti-pull-out groove (6).

4. A polytetrafluoroethylene corrugated hose assembly with a fluorosilicone rubber sealing ring according to claim 3, characterized in that, The sealing groove (7) is provided on the outer surface of the core rod (9) in multiple ways, and the fluorosilicone rubber sealing ring (8) is sleeved in at least two of the sealing grooves (7).

5. A polytetrafluoroethylene corrugated hose assembly with a fluorosilicone rubber sealing ring according to claim 1, characterized in that, The polytetrafluoroethylene corrugated inner tube (2) is a corrugated tube with a conductive carbon black layer (1) on its inner wall.

6. A polytetrafluoroethylene corrugated hose assembly with a fluorosilicone rubber sealing ring according to claim 1, characterized in that, The glass fiber cloth layer (3) is a glass fiber impregnated cloth.

7. A polytetrafluoroethylene corrugated hose assembly with a fluorosilicone rubber sealing ring according to claim 1, characterized in that, The stainless steel wire reinforcement layer (4) is made by stranding multiple stainless steel wires together.

8. A polytetrafluoroethylene corrugated hose assembly with a fluorosilicone rubber sealing ring according to claim 1, characterized in that, The main material of the fireproof rubber layer (4) is silicone rubber.

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