Stainless steel precision taper tube for compressor system

Abstract

The application discloses a stainless steel precision conical pipe for a compressor system, and adopts a multi-pass cold rolling process to be formed, and intermediate annealing treatment is carried out between each pass. The application is suitable for the field of refrigeration compressors, adopts ultra-pure ferrite stainless steel, precision conical processing, is formed through the multi-pass cold rolling process, and 650 DEG C*5min intermediate annealing is carried out between each pass, so that the corrosion resistance of the conical pipe is ensured, the full-length wall thickness tolerance of the conical pipe is reduced, and the ovality of the conical pipe is improved.

Description

Technical Field

[0001] This invention relates to the field of refrigeration compressors, and more particularly to a stainless steel precision tapered tube for compressor systems. Background Technology

[0002] In refrigeration compressor systems, tapered tubes are key components for high-pressure fluid transmission. The long-term use of copper (such as TP2 and C1220) directly impacts system energy efficiency due to its sealing performance, pressure resistance, and flow channel design. Traditional carbon steel tapered tubes suffer from corrosion susceptibility and heavy weight, while the application of stainless steel improves corrosion resistance, but challenges remain in precision forming processes. Summary of the Invention

[0003] In view of the above problems, the present invention is proposed to provide solutions that overcome or at least partially solve the above problems.

[0004] According to one aspect of the present invention, a stainless steel precision tapered tube for a compressor system is provided, the stainless steel precision tapered tube being formed by a multi-pass cold rolling process, with intermediate annealing treatment performed between each pass.

[0005] Preferably, the stainless steel precision tapered tube is made of 22Cr-2Mo-0.05N ultrapure ferritic stainless steel.

[0006] Preferably, in the annealing process, the annealing temperature is 650℃ and the annealing time is 5min, so that the hardness of the stainless steel precision tapered tube is controlled at HV200±10.

[0007] Preferably, the stainless steel precision tapered tube includes a first main body, a first connecting section, a second main body, a second connecting section, a third main body, a fourth main body, and an end, arranged sequentially. The first main body, the second main body, and the third main body all adopt a cylindrical structure, and the first connecting section, the second connecting section, the fourth main body, and the end all adopt a structure with a gradually increasing diameter from left to right.

[0008] Preferably, in the cold rolling process, interstitial solid solution strengthening is formed by nitrogen microalloying, and TiC is formed by fixing free C with Ti element.

[0009] In this invention, ultra-pure ferritic stainless steel is used, and the tube is precision tapered and formed through a multi-pass cold rolling process. An intermediate annealing process of 650℃×5min is performed between each pass to ensure the corrosion resistance of the tapered tube, reduce the overall wall thickness tolerance of the tapered tube, and improve the ellipticity of the tapered tube.

[0010] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, and in order to make the above and other objects, features and advantages of the present invention more apparent and understandable, specific embodiments of the present invention are described below. Attached Figure Description

[0011] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a schematic diagram of the overall structure provided in an embodiment of the present invention; 1. Main body No. 1; 2. Main body No. 2; 3. Main body No. 3; 4. Main body No. 4; 5. Connecting section No. 1; 6. Connecting section No. 2; 7. End. Detailed Implementation

[0013] Exemplary embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

[0014] The terms "comprising" and "having," and any variations thereof, in the specification, embodiments, claims, and drawings of this invention are intended to cover non-exclusive inclusion, such as including a series of steps or units.

[0015] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0016] A stainless steel precision tapered tube for compressor systems, such as Figure 1 As shown, the stainless steel precision tapered tube is formed by a multi-pass cold rolling process, with intermediate annealing treatment between each pass.

[0017] In one possible implementation, the stainless steel precision tapered tube is made of 22Cr-2Mo-0.05N ultrapure ferritic stainless steel.

[0018] In one possible implementation, the annealing process is carried out at a temperature of 650°C for 5 minutes, so that the hardness of the stainless steel precision tapered tube is controlled at HV200±10.

[0019] In one possible implementation, the stainless steel precision tapered tube includes a first main body 1, a first connecting section 5, a second main body 2, a second connecting section 6, a third main body 3, a fourth main body 4, and an end 7 arranged sequentially. The first main body 1, the second main body 2, and the third main body 3 all adopt a cylindrical structure, and the first connecting section 5, the second connecting section 6, the fourth main body 4, and the end 7 all adopt a structure in which the diameter gradually increases from left to right.

[0020] In one possible implementation, during the cold rolling process, interstitial solid solution strengthening is achieved through nitrogen microalloying, and TiC is formed by fixing free C with Ti elements.

[0021] Furthermore, the obtained product has a tensile strength ≥550MPa (120% higher than that of copper); pitting resistance equivalent PREN ≥35 (passed ISO 17826 salt spray test for 2000h); thermal conductivity increased to 28W / (m·K); overall wall thickness tolerance ≤±0.015mm (reaching the level of copper tubes); and ellipticity <0.3%D (D is the tube diameter).

[0022] By adopting the above technical solution: Compared with the prior art, the present invention has the following advantages: (I) Breakthrough in material properties (II) Improved economic efficiency of the process Manufacturing costs: Copper pipe material cost: ¥85-95 / kg (average price in 2023); Stainless steel pipe of this invention: ¥32-38 / kg (443M stainless steel); Unit cost reduced by 52-60% (taking Φ20mm×1m pipe as an example); Processing efficiency: Traditional spinning forming: 3-5 passes (88% pass rate); Cold rolling process of this invention: 2-3 passes (99.2% pass rate), production efficiency is increased by 40%, and scrap rate is reduced by 11.2 percentage points.

[0023] (III) System Performance Optimization Sealing reliability: Leakage rate of copper brazing: 3.2 × 10⁻⁶ －8 Pa·m 3 / s; Stepped brazing of this invention: <1×10 －9 Pa·m 3 / s, the sealing level is improved by one order of magnitude.

[0024] The above specific embodiments further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above are merely specific embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A stainless steel precision tapered tube for use in compressor systems, characterized in that: The stainless steel precision tapered tube is formed by a multi-pass cold rolling process, with intermediate annealing treatment between each pass.

2. The stainless steel precision tapered tube for a compressor system as described in claim 1, characterized in that: The stainless steel precision tapered tube is made of 22Cr-2Mo-0.05N ultrapure ferritic stainless steel.

3. The stainless steel precision tapered tube for a compressor system as described in claim 1, characterized in that: In the annealing process, the annealing temperature is 650℃ and the annealing time is 5min, so that the hardness of the stainless steel precision tapered tube is controlled at HV200±10.

4. The stainless steel precision tapered tube for a compressor system as described in claim 1, characterized in that: The stainless steel precision tapered tube includes a first main body (1), a first connecting section (5), a second main body (2), a second connecting section (6), a third main body (3), a fourth main body (4), and an end (7) arranged in sequence. The first main body (1), the second main body (2), and the third main body (3) all adopt a cylindrical structure. The first connecting section (5), the second connecting section (6), the fourth main body (4), and the end (7) all adopt a structure with a gradually increasing diameter from left to right.

5. A stainless steel precision tapered tube for a compressor system as described in claim 1, characterized in that: In the cold rolling process, interstitial solid solution strengthening is achieved through nitrogen microalloying, and TiC is formed by fixing free C with Ti element.

Images