Double-layer pipe with inner layer and outer layer engaged and self-locked

Abstract

The utility model relates to the technical field of pipelines, aims to solve the problems that in the prior art, connection of an inner layer and an outer layer of a double-layer pipe is unreliable, and the inner layer and the outer layer are prone to being separated from each other, and provides a double-layer pipe with the inner layer and the outer layer meshed and self-locked. The groove comprises a concave part and a lock catch part, the lock catch part is located below the concave part, the width of the lock catch part is larger than that of the concave part, and the lock catch part is provided with a left wing part and a right wing part; the inner wall of the outer-layer pipe is provided with protrusions, the protrusions are matched with the grooves, the protrusions are located in the grooves, and the protrusions are matched with the grooves to enable the inner-layer pipe and the outer-layer pipe to be meshed and self-locked. According to the double-layer pipe, the groove is formed in the outer wall of the inner-layer pipe, the lock catch part of the groove is provided with the left wing part and the right wing part, and the protrusion arranged on the inner wall of the outer-layer pipe is matched with the groove, so that interlocking of the protrusion and the groove can be better achieved, the inner-layer pipe and the outer-layer pipe are meshed and self-locked, and separation of the inner-layer pipe and the outer-layer pipe is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of pipelines, in particular to a double-layer pipe with inner and outer layers biting and self-locking. Background Art

[0002] In the prior art, the connection between the inner and outer layers of some double-layer pipes is not reliable, and the inner and outer layers are easy to separate from each other. In particular, double-layer pipes with different raw materials for the inner and outer layers or modified materials with different properties for the inner and outer layers cannot make good use of the principle that similar materials for the inner and outer layers dissolve in each other, and the inner and outer layers are prone to stratification after extrusion cooling, resulting in the separation of the inner and outer layers of the pipe.

[0003] Chinese invention patent CN109796662A discloses a bonding part of a PVC / PE blend and PE and a preparation method thereof. It proposes that the cooled PE / PVC melt is cooled and molded to 80-100°C by injection molding, and then the molten PE material is extruded and combined with the PVC / PE mixed cooling molded part. Since the physical cooling speed and temperature of the two parts are different, the cooling and shrinkage speeds of the two parts are different during the spray cooling process, resulting in the connection part being not strong enough and prone to stratification problems. Utility Model Content

[0004] The utility model aims to provide a double-layer pipe with inner and outer layers biting and self-locking, so as to solve the problems in the prior art that the inner and outer layers of the double-layer pipe are unreliable in connection and the inner and outer layers are easy to separate from each other.

[0005] The utility model is realized by adopting the following technical solutions:

[0006] The utility model provides a double-layer tube with inner and outer layers interlocking and self-locking, comprising an inner tube and an outer tube, wherein the inner tube is located inside the outer tube, and a groove is arranged on the outer wall of the inner tube, wherein the groove comprises a concave portion and a locking portion, wherein the locking portion is located below the concave portion, wherein the width of the locking portion is greater than the width of the concave portion, and the locking portion has two left and right wings;

[0007] A protrusion is arranged on the inner wall of the outer tube, the protrusion is matched with the groove, the protrusion is located in the groove, and the protrusion cooperates with the groove to bite and self-lock the inner tube and the outer tube.

[0008] As the preferred technical solution:

[0009] The width of the groove at the bottom is greater than the width at the notch.

[0010] As the preferred technical solution:

[0011] The cross section of the groove is in an inverted T shape.

[0012] As the preferred technical solution:

[0013] The outer diameter of the inner tube is equal to the inner diameter of the outer tube.

[0014] As the preferred technical solution:

[0015] The groove is arranged along the length direction of the inner tube.

[0016] As the preferred technical solution:

[0017] The double-layer tube is formed by co-extruding the inner layer tube and the outer layer tube through a die.

[0018] As the preferred technical solution:

[0019] The inner layer tube and the outer layer tube are made of the same material or different materials.

[0020] As the preferred technical solution:

[0021] When the inner tube and the outer tube are made of different materials, the raw materials of the inner tube and the outer tube in molten state are respectively introduced into the inner layer and the outer layer of the mold to form the interlocking inner tube and the outer tube.

[0022] As the preferred technical solution:

[0023] The outer layer pipe is made of a mixture of PVC and PE, and the inner layer pipe is made of PE material.

[0024] In summary, due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0025] The double-layer tube of the utility model is provided with a groove on the outer wall of the inner tube, and the groove includes a recessed portion and a locking portion, the locking portion has two left and right wings, and the protrusion provided on the inner wall of the outer tube is adapted to the groove, which can better realize the interlocking of the protrusion and the groove, so that the inner tube and the outer tube are engaged and self-locked, the inner and outer layer bonding area is increased, the bonding force of the inner and outer layer pipes is improved, and the inner and outer layer pipes can be effectively prevented from being separated after long-term use. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a cross-sectional schematic diagram of a double-layer tube with inner and outer layers interlocking and self-locking according to the utility model.

[0027] Icon: 1-inner tube, 2-outer tube, 3-groove, 301-recess, 302-locking part, 4-protrusion. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the utility model clearer, the technical solution in the embodiments of the utility model will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0029] Example 1

[0030] like Figure 1 As shown, this embodiment proposes a double-layer tube with inner and outer layers interlocking and self-locking, including an inner tube 1 and an outer tube 2, wherein the inner tube 1 is located inside the outer tube 2, and the outer diameter of the inner tube 1 is equal to the inner diameter of the outer tube 2.

[0031] A groove 3 is provided on the outer wall of the inner tube 1, and the width of the groove 3 at the bottom position is greater than the width at the notch position. The groove 3 includes a recessed portion 301 and a locking portion 302, the locking portion 302 is located below the recessed portion 301, the width of the locking portion 302 is greater than the width of the recessed portion 301, and the locking portion 302 has two left and right wings. In this embodiment, the cross section of the groove 3 is in an inverted T shape.

[0032] A protrusion 4 is provided on the inner wall of the outer tube 2, and the protrusion 4 is adapted to the groove 3. The protrusion 4 is located in the groove 3, and the protrusion 4 cooperates with the groove 3 to engage and self-lock the inner tube 1 and the outer tube 2.

[0033] With the above structure, the inner tube 1 and the outer tube 2 are self-locking with each other, and at the same time the bonding area of ​​the inner and outer tubes is increased by 60%-85%, thereby ensuring the bonding strength of the inner and outer tubes and effectively preventing the inner and outer tubes from separating after long-term use.

[0034] The utility model is not only applicable to pipes with inner and outer layers of the same material, but also applicable to pipes with inner and outer layers of different materials, so as to facilitate the formation of pipes with different inner and outer layer properties and enhance the bonding strength of the inner and outer layers of pipes of different materials.

[0035] The inner tube 1 and the outer tube 2 are extruded through a die at the same time, and after extrusion, the inner tube 1 and the outer tube 2 are in an interlocked state.

[0036] When the inner tube 1 and the outer tube 2 are made of different materials, for example, when the inner tube 1 is made of pure PE material and the outer tube 2 is made of a modified mixture of PE and PVC, the molten PVC and PE mixture and the molten PE material are directly passed through the inner and outer layers of the mold to form a strong bonding structure with more advantageous connection strength, overcoming the problem in the prior art that the cooling speed and cooling shrinkage speed of the two materials are different, resulting in the connection part being not strong enough.

[0037] The above description is only the preferred embodiment of the utility model, and is not intended to limit the utility model. For those skilled in the art, the utility model can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the utility model shall be included in the protection scope of the utility model.

Claims

1. A double-layer tube with inner and outer layers interlocking and self-locking, characterized in that: It comprises an inner tube and an outer tube, wherein the inner tube is located inside the outer tube, a groove is arranged on the outer wall of the inner tube, the groove comprises a concave portion and a locking portion, the locking portion is located below the concave portion, the width of the locking portion is greater than the width of the concave portion, and the locking portion has two left and right wings; A protrusion is arranged on the inner wall of the outer tube, the protrusion is matched with the groove, the protrusion is located in the groove, and the protrusion cooperates with the groove to bite and self-lock the inner tube and the outer tube.

2. The double-layer tube with inner and outer layers interlocking and self-locking according to claim 1, characterized in that: The width of the groove at the bottom is greater than the width at the notch.

3. The double-layer tube with inner and outer layers interlocking and self-locking according to claim 1, characterized in that: The cross section of the groove is in an inverted T shape.

4. The double-layer tube with inner and outer layers interlocking and self-locking according to claim 1, characterized in that: The outer diameter of the inner tube is equal to the inner diameter of the outer tube.

5. The double-layer tube with inner and outer layers interlocking and self-locking according to claim 1, characterized in that: The groove is arranged along the length direction of the inner tube.

6. The double-layer tube with inner and outer layers interlocking and self-locking according to claim 1, characterized in that: The double-layer tube is formed by co-extruding the inner layer tube and the outer layer tube through a die.

7. The double-layer tube with inner and outer layers interlocking and self-locking according to claim 1, characterized in that: The inner layer tube and the outer layer tube are made of the same material or different materials.

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