Special polytetrafluoroethylene steel lining straight pipe for chemical industry

Abstract

The utility model relates to the field of chemical engineering pipelines, in particular to a special polytetrafluoroethylene steel lining straight pipe for chemical engineering, which comprises a steel pipe, a lining pipe and a lining sealing pipe, the lining pipe is fixed on the inner side of the steel pipe and is made of polytetrafluoroethylene, flange rings are fixedly connected to two ends of the steel pipe, and the lining sealing pipe is made of polytetrafluoroethylene. A multi-stage step face is arranged at the position, close to the flange ring, of the inner side of the steel pipe, an annular end is fixedly connected to the end of the lining pipe and located on the inner side of the multi-stage step face, a first annular opening is formed in the inner side of the annular end, and an annular protruding part is arranged at the end, away from the lining pipe, of the annular end. According to the utility model, the end part structure of the lining pipe is improved and the lining sealing pipe structure is arranged, so that good sealing performance can be achieved, and good corrosion resistance is achieved.

Description

Technical Field

[0001] The utility model relates to the field of chemical pipelines, in particular to a polytetrafluoroethylene steel-lined straight pipe dedicated to the chemical industry. Background Art

[0002] Polytetrafluoroethylene can basically meet all chemical media in the temperature range of -60 degrees to 200 degrees, has high corrosion resistance, and is used as the lining of steel pipes. Steel pipes with polytetrafluoroethylene linings have high structural strength, strong rigidity, and good corrosion resistance, and are often used in chemical piping systems.

[0003] Chemical pipeline systems need to transport highly corrosive media, and polytetrafluoroethylene linings can meet the use requirements. However, at the pipe connections, the media is prone to overflow, and the sealing rings used in traditional sealing structures cannot resist high corrosion. Therefore, the utility model provides a polytetrafluoroethylene steel-lined straight pipe for chemical industry. Utility Model Content

[0004] The utility model aims to solve the shortcomings in the prior art and proposes a special polytetrafluoroethylene steel-lined straight pipe for chemical industry.

[0005] In order to achieve the above-mentioned purpose, the utility model adopts the following technical scheme: a chemical special polytetrafluoroethylene steel lining straight pipe, comprising a steel pipe and an inner lining pipe, wherein the inner lining pipe is fixed on the inner side of the steel pipe, and the material of the inner lining pipe is polytetrafluoroethylene, both ends of the steel pipe are fixedly connected with flange rings, the inner side of the steel pipe and close to the flange ring are provided with a multi-stepped surface, the end of the inner lining pipe and the inner side of the multi-stepped surface are fixedly connected with an annular end head, the inner side of the annular end head is provided with a first annular opening, and the end of the annular end head away from the inner lining pipe is provided with an annular protrusion;

[0006] It also includes: an inner lining sealing tube, which is made of polytetrafluoroethylene material, and an annular sheet is fixedly connected to the outer side of the inner lining sealing tube. The inner lining sealing tube extends toward both ends of the annular sheet to form an insert portion, and the insert portion corresponds to the first annular opening. An annular recess is opened at the end of the annular sheet, and the annular protrusion corresponds to the annular recess.

[0007] As a further description of the above technical solution:

[0008] A gasket portion is fixedly connected to the outer side of the annular sheet, a V-shaped opening is arranged on the outer side of the gasket portion, and a U-shaped opening is opened at the end of the gasket portion.

[0009] As a further description of the above technical solution:

[0010] The liner sealing tube, the annular sheet and the gasket ring are an integrated structure, and a steel sheet is arranged on the inner side of the annular sheet.

[0011] As a further description of the above technical solution:

[0012] The end of the flange ring is provided with a plurality of flange holes distributed in an annular manner.

[0013] As a further description of the above technical solution:

[0014] A step is arranged between the end of the annular end cap and the end of the flange ring, and the annular sheet is located on the inner side of the step.

[0015] As a further description of the above technical solution:

[0016] The inner diameter of the liner sealing pipe is equal to the inner diameter of the liner pipe.

[0017] As a further description of the above technical solution:

[0018] The outer side of the bottom of the annular end head corresponds to the multi-step surface.

[0019] The utility model has the following beneficial effects:

[0020] 1. Compared with the prior art, this chemical-specific polytetrafluoroethylene steel-lined straight pipe can achieve good sealing performance and good corrosion resistance by improving the end structure of the inner liner pipe and setting an inner liner sealing pipe structure; specifically, a first annular opening is set on the inner side of the annular end head, an annular protrusion is fixedly connected to the top, a plug-in portion is formed at the bottom of the inner liner sealing pipe, an annular sheet is connected to the outside, and an annular recess is opened at the end of the annular sheet to form two sets of sealing structures, in which the plug-in portion corresponds to the first annular opening and the annular protrusion corresponds to the annular recess; and the material of the inner liner sealing pipe is polytetrafluoroethylene, which can achieve the effect of sealing and corrosion resistance. Compared with the existing sealing structure, this pipeline is suitable for use in the chemical industry.

[0021] 2. Compared with the prior art, the polytetrafluoroethylene steel-lined straight pipe for chemical industry has a steel sheet arranged inside the annular sheet, so that the strength of the integrated structure composed of the liner sealing pipe, the annular sheet and the gasket ring part is higher. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a three-dimensional schematic diagram of a polytetrafluoroethylene steel-lined straight pipe for chemical industry proposed by the utility model;

[0023] Figure 2 This is a cross-sectional schematic diagram of a polytetrafluoroethylene steel-lined straight pipe for chemical industry proposed by the utility model;

[0024] Figure 3 for Figure 2 A partial enlarged view of point A in the middle.

[0025] Legend:

[0026] 1. Steel pipe; 2. Liner pipe; 3. Flange ring; 4. Multi-step surface; 5. Ring end; 6. First ring mouth; 7. Ring protrusion; 8. Flange hole; 9. Liner sealing pipe; 10. Insert part; 11. Ring notch; 12. Gasket part; 13. V-shaped mouth; 14. Steel sheet; 15. U-shaped mouth. DETAILED DESCRIPTION

[0027] Reference Figure 1-Figure 3 The utility model provides a special polytetrafluoroethylene steel lined straight pipe for chemical industry, comprising a steel pipe 1, an inner lining pipe 2 and an inner lining sealing pipe 9. The inner lining pipe 2 is fixed on the inner side of the steel pipe 1, and the material of the inner lining pipe 2 is polytetrafluoroethylene. Both ends of the steel pipe 1 are fixedly connected with flange rings 3, so that the steel lined straight pipe can be connected to the pipeline system by bolt groups. A multi-step step surface 4 is arranged on the inner side of the steel pipe 1 and close to the flange ring 3. An annular end cap 5 is fixedly connected to the end of the inner lining pipe 2 and is located on the inner side of the multi-step step surface 4. The outer side of the bottom of the annular end cap 5 corresponds to the multi-step step surface 4 to form a stable structure, which effectively prevents the steel pipe 1 and the inner lining pipe 2 from sliding relative to each other. A first annular opening 6 is arranged on the inner side of the annular end cap 5, and an annular protrusion 7 is provided at the end of the annular end cap 5 away from the inner lining pipe 2.

[0028] The material of the lining sealing tube 9 is polytetrafluoroethylene, and an annular sheet is fixedly connected to the outer side of the lining sealing tube 9. The lining sealing tube 9 extends toward both ends of the annular sheet to form an insert portion 10, and the insert portion 10 corresponds to the first annular opening 6. An annular recess 11 is provided at the end of the annular sheet, and the annular protrusion 7 corresponds to the annular recess 11.

[0029] When the device is in use, two steel-lined straight pipes are fixedly connected, and the inner lining sealing pipe 9 is arranged between the two steel-lined straight pipes. When connected by bolts, the plug-in portion 10 corresponds to the first annular opening 6, and the annular protrusion 7 corresponds to the annular recess 11, forming a good sealing effect. Moreover, the material of the inner lining sealing pipe 9 is polytetrafluoroethylene, which is the same as the material of the inner lining pipe 2, and both have high corrosion resistance.

[0030] A gasket portion 12 is fixedly connected to the outer side of the annular sheet, and a V-shaped opening 13 is arranged on the outer side of the gasket portion 12 .

[0031] When the two flange rings 3 squeeze the gasket ring portion 12, the V-shaped opening 13 is easily deformed, making the connection between the two steel-lined straight pipes tighter, especially after the flange ring 3 has a certain deformation, it can still ensure a higher clamping force.

[0032] The end of the gasket ring portion 12 is provided with a U-shaped opening 15. The end of the flange ring 3 is provided with a plurality of annularly distributed flange holes 8. The number and position of the U-shaped opening 15 and the flange holes 8 correspond.

[0033] The liner sealing tube 9, the annular sheet, and the gasket ring portion 12 are an integral structure, and the inner side of the annular sheet is provided with a steel sheet 14. The integral structure composed of the liner sealing tube 9, the annular sheet, and the gasket ring portion 12 is preferably manufactured by injection molding.

[0034] A step is provided between the end of the annular end cap 5 and the end of the flange ring 3, and the annular sheet is located on the inner side of the step, forming a sealing contact surface, further improving the sealing performance when two steel-lined straight pipes are connected.

[0035] The inner diameter of the liner sealing pipe 9 is equal to the inner diameter of the liner pipe 2. The inner diameter of the pipeline system formed by the connection does not change at the joint, which is convenient for the flow of the internal medium.

[0036] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A polytetrafluoroethylene steel-lined straight pipe for chemical industry, comprising a steel pipe (1) and an inner lining pipe (2), wherein the inner lining pipe (2) is fixed to the inner side of the steel pipe (1) and the material of the inner lining pipe (2) is polytetrafluoroethylene, characterized in that: Both ends of the steel pipe (1) are fixedly connected with flange rings (3), the inner side of the steel pipe (1) and close to the flange ring (3) are provided with a multi-step surface (4), the end of the inner liner (2) and located inside the multi-step surface (4) is fixedly connected with an annular end cap (5), the inner side of the annular end cap (5) is provided with a first annular opening (6), and the end of the annular end cap (5) away from the inner liner (2) is provided with an annular protrusion (7); It also includes: an inner liner sealing tube (9), the inner liner sealing tube (9) is made of polytetrafluoroethylene, the outer side surface of the inner liner sealing tube (9) is fixedly connected to an annular sheet, the inner liner sealing tube (9) extends toward both ends of the annular sheet to form an inserting portion (10), the inserting portion (10) corresponds to the first annular opening (6), an annular recess (11) is provided at the end of the annular sheet, and the annular protrusion (7) corresponds to the annular recess (11).

2. A polytetrafluoroethylene steel-lined straight pipe for chemical industry according to claim 1, characterized in that: A gasket portion (12) is fixedly connected to the outer side of the annular sheet, a V-shaped opening (13) is arranged on the outer side of the gasket portion (12), and a U-shaped opening (15) is opened at the end of the gasket portion (12).

3. A polytetrafluoroethylene steel-lined straight pipe for chemical industry according to claim 2, characterized in that: The inner liner sealing tube (9), the annular sheet and the gasket ring portion (12) are an integrated structure, and a steel sheet (14) is provided on the inner side of the annular sheet.

4. A polytetrafluoroethylene steel-lined straight pipe for chemical industry according to claim 1, characterized in that: The end of the flange ring (3) is provided with a plurality of flange holes (8) distributed in an annular manner.

5. The polytetrafluoroethylene steel-lined straight pipe for chemical industry according to claim 1, characterized in that: A step is provided between the end of the annular end cap (5) and the end of the flange ring (3), and the annular sheet is located on the inner side of the step.

6. A polytetrafluoroethylene steel-lined straight pipe for chemical industry according to claim 1, characterized in that: The inner diameter of the liner sealing tube (9) is equal to the inner diameter of the liner tube (2).

7. The polytetrafluoroethylene steel-lined straight pipe for chemical industry according to claim 1, characterized in that: The outer side of the bottom of the annular end head (5) corresponds to the multi-step surface (4).

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