Heat-resistant stainless steel tube and preparation process thereof

Abstract

The heat-resistant stainless steel pipe comprises a high-temperature-resistant stainless steel pipe body (1), a set of annularly-distributed T-shaped axial grooves (2) are formed in the inner wall of the high-temperature-resistant stainless steel pipe body (1), heat insulation reinforcing ribs (3) are arranged in the T-shaped axial grooves (2), and a polytetrafluoroethylene coating (4) and a high-temperature-resistant composite coating (5) are arranged on the inner wall of the high-temperature-resistant stainless steel pipe body (1). A set of annular grooves (6) distributed side by side are formed in the outer wall face of the high-temperature-resistant stainless steel pipe body (1), and heat insulation rings (7) are arranged in the annular grooves (6). And the high-temperature-resistant composite coating (5) comprises a high-temperature-resistant layer (501) and an anti-sticking wear-resistant layer (502). The heat-insulating material has the characteristic of effectively improving the heat-insulating property.

Description

Technical Field

[0001] The invention relates to a stainless steel pipe, in particular to a heat-resistant stainless steel pipe and a preparation process thereof. Background Art

[0002] At present, the common high-temperature resistant stainless steel pipe is mainly 310S (0Cr25Ni20) stainless steel, which is an austenitic chromium-nickel stainless steel with good oxidation resistance and corrosion resistance. Because of the higher percentage of chromium and nickel, it has much better creep strength, can continue to work at high temperatures, and has good high temperature resistance. Due to the high content of nickel (Ni) and chromium (Cr), it has good oxidation resistance, corrosion resistance, acid and alkali resistance, and high temperature resistance. However, the existing high-temperature resistant stainless steel pipe has poor thermal insulation performance. Therefore, the existing technology has the problem of poor thermal insulation performance. Summary of the invention

[0003] The object of the present invention is to provide a heat-resistant stainless steel pipe and a preparation process thereof. The present invention has the characteristic of being able to effectively improve the thermal insulation performance.

[0004] The technical solution of the present invention is as follows: a heat-resistant stainless steel pipe comprises a high-temperature resistant stainless steel pipe body, the inner wall of the high-temperature resistant stainless steel pipe body is provided with a group of annularly distributed T-shaped axial grooves, the T-shaped axial grooves are provided with heat-insulating reinforcement ribs, the inner wall of the high-temperature resistant stainless steel pipe body is provided with a polytetrafluoroethylene coating and a high-temperature resistant composite coating; the outer wall of the high-temperature resistant stainless steel pipe body is provided with a group of annular grooves distributed side by side, the annular grooves are provided with heat-insulating rings; the high-temperature resistant composite coating comprises a high-temperature resistant layer and an anti-sticking and wear-resistant layer.

[0005] In the aforementioned heat-resistant stainless steel tube, the outer wall surface of the high-temperature resistant stainless steel tube body is also provided with a scratch-resistant heat-insulating coating.

[0006] In the aforementioned heat-resistant stainless steel pipe, the heat-insulating reinforcement ribs include an inner reinforcement bar with a T-shaped cross-section, and a high-temperature-resistant outer lining layer is arranged outside the inner reinforcement bar.

[0007] The preparation process of the heat-resistant stainless steel pipe comprises the following steps:

[0008] S1, assembling casting mold;

[0009] S2, pouring the molten stainless steel smelting liquid into the casting cavity of the casting mold, and removing the casting mold after cooling and forming to obtain a high temperature resistant stainless steel tube blank;

[0010] S3, cleaning and polishing the high temperature resistant stainless steel tube blank;

[0011] S4. Insert the heat-insulating reinforcing ribs coated with glue into the corresponding T-shaped axial grooves and fix them by bonding;

[0012] S5. Spray polytetrafluoroethylene coating, high temperature resistant layer and anti-sticking and wear-resistant layer on the inner wall of the high temperature resistant stainless steel pipe in sequence;

[0013] S6. Install a heat-insulating ring in the annular groove outside the high-temperature resistant stainless steel pipe, and then spray a scratch-resistant heat-insulating coating.

[0014] Compared with the prior art, the present invention provides a T-shaped axial groove and a heat-insulating reinforcement rib on the inner wall of the high-temperature resistant stainless steel pipe body, and provides a group of annular grooves and heat-insulating rings arranged side by side on the outer wall of the high-temperature resistant stainless steel pipe body, and also applies a polytetrafluoroethylene coating and a high-temperature resistant composite coating on the inner wall of the high-temperature resistant stainless steel pipe body, so that the stainless steel pipe not only has good heat-insulating performance, but also can effectively improve the structural strength. In summary, the present invention has the characteristics of being able to effectively improve the heat-insulating performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of the heat-resistant stainless steel pipe of the present invention.

[0016] The markings in the attached drawings are: 1-high temperature resistant stainless steel pipe body, 2-T-shaped axial groove, 3-thermal insulation reinforcement ribs, 4-polytetrafluoroethylene coating, 5-high temperature resistant composite coating, 6-annular groove, 7-thermal insulation ring, 501-high temperature resistant layer, 502-anti-stick and wear-resistant layer, 8-scratch-resistant thermal insulation coating. DETAILED DESCRIPTION

[0017] The present invention is further described below in conjunction with the accompanying drawings and embodiments, but they are not intended to limit the present invention.

[0018] Example. A heat-resistant stainless steel pipe, comprising: Figure 1 As shown, it includes a high-temperature resistant stainless steel pipe body 1, the inner wall of the high-temperature resistant stainless steel pipe body 1 is provided with a group of annularly distributed T-shaped axial grooves 2, the T-shaped axial grooves 2 are provided with heat-insulating reinforcement ribs 3, the inner wall of the high-temperature resistant stainless steel pipe body 1 is provided with a polytetrafluoroethylene coating 4 and a high-temperature resistant composite coating 5; the outer wall surface of the high-temperature resistant stainless steel pipe body 1 is provided with a group of annular grooves 6 distributed side by side, and an insulation ring 7 is provided in the annular groove 6; the high-temperature resistant composite coating 5 includes a high-temperature resistant layer 501 and an anti-sticking and wear-resistant layer 502.

[0019] The outer wall surface of the high temperature resistant stainless steel tube body 1 is also provided with a scratch resistant heat insulating coating 8 .

[0020] The heat-insulating reinforcement ribs 3 include an inner reinforcement bar with a T-shaped cross-section, and a high-temperature resistant outer lining layer is arranged outside the inner reinforcement bar.

[0021] The preparation process of the heat-resistant stainless steel pipe comprises the following steps:

[0022] S1, assembling casting mold;

[0023] S2, pouring the molten stainless steel smelting liquid into the casting cavity of the casting mold, and removing the casting mold after cooling and forming to obtain a high temperature resistant stainless steel tube blank;

[0024] S3, cleaning and polishing the high temperature resistant stainless steel tube blank;

[0025] S4. Insert the heat-insulating reinforcing ribs coated with glue into the corresponding T-shaped axial grooves and fix them by bonding;

[0026] S5. Spray polytetrafluoroethylene coating, high temperature resistant layer and anti-sticking and wear-resistant layer on the inner wall of the high temperature resistant stainless steel pipe in sequence;

[0027] S6. Install a heat-insulating ring in the annular groove outside the high-temperature resistant stainless steel pipe, and then spray a scratch-resistant heat-insulating coating.

[0028] The casting mold includes a hinged bottom mold and a top mold, both end surfaces of the bottom mold and the top mold are provided with positioning holes, and suction magnets are provided in the positioning holes; one end of the bottom mold and the top mold is provided with a mounting disk, and the side wall surface of the mounting disk is provided with a first positioning magnetic column that matches the positioning hole; a core mold is provided between the bottom mold and the top mold, and the end of the core mold is provided with a fixed disk that matches the other end of the bottom mold and the top mold, and the inner wall surface of the fixed disk is provided with a matching second positioning magnetic column.

[0029] Pull rings are provided on the outer sides of the fixed disc and the installation disc.

[0030] The bottom mold and the top mold both comprise a hollow semi-cylindrical mold body, and a group of semi-circular arc-shaped protrusions are arranged on the inner wall of the hollow cavity of the semi-cylindrical mold body.

[0031] The outer wall of the core mold is provided with a group of annularly distributed T-shaped axial strips.

[0032] During pouring, the mold is coated with a release agent.

[0033] By providing the upper and lower semicircular arc-shaped protrusions to form an arc-shaped protrusion, an annular groove can be formed during casting, and by providing the T-shaped axial strips, a T-shaped axial groove can be formed during casting.

[0034] The cooperation between the first and second positioning magnetic columns and the magnets in the positioning holes facilitates the installation and positioning of the core mold, and ensures that the structure is stable and firm after installation. In addition, the pull ring is provided to facilitate the installation and disassembly of the disk and the core mold.

[0035] A central groove corresponding to the core mold is also provided in the middle of the inner wall of the mounting disc. The end of the core mold is inserted into the central groove to improve the connection strength.

[0036] A pouring port is provided at the upper end of the top mold, and the stainless steel molten liquid is poured into the pouring cavity from the pouring port to form the mold.

[0037] The top mold and the bottom mold are provided with lock buckles away from the hinged ends, and the lock buckles are closed during pouring.

[0038] When removing the mold, open the lock and pull the pull ring outward to separate the mounting disc and the fixed disc on the core mold from the bottom mold and the top mold, continue to pull the core mold outward to separate it from the forming tube, and then rotate the top mold to take out the high-temperature resistant stainless steel tube blank.

Claims

1. Heat-resistant stainless steel pipe, characterized by: The invention comprises a high-temperature resistant stainless steel pipe body (1), wherein the inner wall of the high-temperature resistant stainless steel pipe body (1) is provided with a group of annularly distributed T-shaped axial grooves (2), the T-shaped axial grooves (2) are provided with heat-insulating reinforcing ribs (3), and the inner wall of the high-temperature resistant stainless steel pipe body (1) is provided with a polytetrafluoroethylene coating (4) and a high-temperature resistant composite coating (5); the outer wall surface of the high-temperature resistant stainless steel pipe body (1) is provided with a group of annular grooves (6) distributed side by side, and a heat-insulating ring (7) is provided in the annular grooves (6); and the high-temperature resistant composite coating (5) comprises a high-temperature resistant layer (501) and an anti-sticking and wear-resistant layer (502).

2. The heat-resistant stainless steel pipe according to claim 1, characterized in that: The outer wall surface of the high-temperature resistant stainless steel pipe body (1) is also provided with a scratch-resistant heat-insulating coating (8).

3. The heat-resistant stainless steel pipe according to claim 1, characterized in that: The heat-insulating reinforcement ribs (3) comprise an inner reinforcement bar with a T-shaped cross section, and a high-temperature resistant outer lining layer is arranged outside the inner reinforcement bar.

4. The process for preparing a heat-resistant stainless steel pipe according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1, assembling casting mold; S2, pouring the molten stainless steel smelting liquid into the casting cavity of the casting mold, and removing the casting mold after cooling and forming to obtain a high temperature resistant stainless steel tube blank; S3, cleaning and polishing the high temperature resistant stainless steel tube blank; S4. Insert the heat-insulating reinforcing ribs coated with glue into the corresponding T-shaped axial grooves and fix them by bonding; S5. Spray polytetrafluoroethylene coating, high temperature resistant layer and anti-sticking and wear-resistant layer on the inner wall of the high temperature resistant stainless steel pipe in sequence; S6. Install a heat-insulating ring in the annular groove outside the high-temperature resistant stainless steel pipe, and then spray a scratch-resistant heat-insulating coating.

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