Lightweight high-strength seamless steel pipe for fitness equipment and production process thereof

Abstract

This invention relates to the field of metallic materials technology, specifically disclosing a lightweight, high-strength seamless steel pipe for fitness equipment and its manufacturing process. The manufacturing process for the lightweight, high-strength seamless steel pipe for fitness equipment includes the following steps: 1. Normalizing a high-strength low-alloy steel pipe to obtain a pre-treated steel pipe; 2. Polishing the surface of the pre-treated steel pipe to obtain a polished steel pipe; 3. Spraying a protective liquid onto the surface of the polished steel pipe and drying it to obtain a pre-protected steel pipe; 4. Heating the pre-protected steel pipe to 100-105℃, holding it at that temperature for 20-30 minutes, and allowing it to cool naturally to obtain the lightweight, high-strength seamless steel pipe for fitness equipment. The protective liquid includes: solvent, water-based acrylic resin, film-forming aid, filler, coupling agent, processing aid, and modifier; the modifier is a compound of guar gum, guar gum, and jujube gum. This invention has the advantage of further improving the corrosion resistance of the lightweight, high-strength seamless steel pipe.

Description

Technical Field

[0001] This invention relates to the field of metallic materials, and in particular to a lightweight, high-strength seamless steel pipe for fitness equipment and its manufacturing process. Background Technology

[0002] Fitness equipment is used to assist in exercise. Due to the fast pace of life, more and more consumers tend to exercise at home, and the demand for home fitness equipment continues to rise. Compared with traditional fitness equipment, home fitness equipment is more valued for its convenience, and lightweight design is the key to improving the convenience of fitness equipment.

[0003] By using thin-walled steel pipes as the supporting structure of fitness equipment, the weight of the equipment can be effectively reduced, while the use of high-strength steel to make thin-walled steel pipes ensures its strength and guarantees the safety of the equipment.

[0004] However, high-strength steel generally has poor corrosion resistance. In particular, fitness equipment is easily corroded by sweat, which contains salt and is highly corrosive. This causes the steel pipe to dissolve and rust, leading to a decrease in strength. Moreover, because thin-walled steel pipes have thin walls, even slight corrosion can seriously affect their overall strength.

[0005] Currently, thin-walled steel pipes are protected by spraying rust inhibitors with acrylic resin as the main component to form a protective film. Water-based acrylic resin is low in cost and relatively environmentally friendly, making it the mainstream rust prevention method. However, the corrosion resistance of the protective film formed by existing rust inhibitors with acrylic resin as the main component is relatively average. Under prolonged exposure to high temperature and humidity, localized rusting is still likely to occur, which is difficult to meet the usage requirements. Therefore, there is still room for improvement. Summary of the Invention

[0006] To further improve the corrosion resistance of lightweight high-strength seamless steel pipes, this application provides a lightweight high-strength seamless steel pipe for fitness equipment and its manufacturing process.

[0007] In a first aspect, this application provides a manufacturing process for lightweight, high-strength seamless steel pipes used in fitness equipment, employing the following technical solution: A manufacturing process for lightweight, high-strength seamless steel pipes used in fitness equipment includes the following steps: Step 1) The high-strength low-alloy steel pipe is normalized to obtain a pretreated steel pipe; Step 2) Polish the surface of the pretreated steel pipe to obtain a polished steel pipe; Step 3) Spray a protective liquid onto the surface of the polished steel pipe and let it dry to obtain a pre-protected steel pipe; Step 4) Heat the pre-protected steel pipe to 100-105℃, hold for 20-30 minutes, and let it cool naturally to obtain a lightweight, high-strength seamless steel pipe for fitness equipment. The protective liquid comprises the following components in parts by weight: Solvent: 28.46-36.64 parts; 43-47 parts of water-based acrylic resin; Film-forming aid 2.8-3.2 parts; 11-13 parts of filler; 0.12-0.18 parts of coupling agent; Processing aids: 1.4-2.4 parts; Modifier 5.04-5.76 parts; The modifier is a compound of guar gum, guar gum, and jujube gum.

[0008] By adopting the above technical solution, and by adding a modifier composed of guar gum, guar gum, and jujube gum to the protective liquid, combined with the heating and heat preservation process in step 4, the gel structure formed by the modifier and the structure of the acrylic resin complement each other, which can significantly improve the airtightness of the protective layer, better block water vapor and oxygen, thereby making the protection of the steel pipe better, significantly improving the corrosion resistance, making the seamless steel pipe less prone to corrosion and resulting in a decrease in strength, and having higher safety and stability, thus better meeting the needs of fitness equipment.

[0009] Normalizing treatment can effectively refine the grains and eliminate the internal stress generated during thinning and forming, thereby simultaneously improving the dimensional stability, bending strength and stress corrosion resistance of the steel pipe, resulting in higher quality steel pipe.

[0010] Preferably, the mass ratio of guar gum, guar gum, and jujube gum in the modifier is 4.2-4.8:0.42-0.48:0.42-0.48.

[0011] By adopting the above technical solution and by specifically selecting the mass ratio of guar gum, guar gum, and jujube gum, the protective layer formed by the protective liquid can better protect the steel pipe, resulting in better corrosion resistance and more stable steel pipe quality.

[0012] Preferably, the processing aid is a compound of defoamer, dispersant, wetting agent and pH adjuster.

[0013] By adopting the above technical solution and adding defoamer, dispersant, wetting agent and pH adjuster, the quality of the protective liquid is stabilized, the effect of spraying on steel pipes is better, the construction is more convenient, and the quality of the steel pipes produced is better.

[0014] Preferably, the mass ratio of the defoamer, dispersant, wetting agent, and pH adjuster in the processing aid is 0.4-0.6: 0.8-1.2: 0.1-0.3: 0.1-0.3.

[0015] By adopting the above technical solution and specifically selecting the mass ratio of defoamer, dispersant, wetting agent, and pH adjuster, the stability of the protective solution can be improved even more effectively.

[0016] Preferably, the film-forming aid is propylene glycol phenyl ether.

[0017] By adopting the above technical solution and specifically selecting propylene glycol phenyl ether, the acrylic resin achieves better film-forming effect, stable quality, and better protection of the steel pipe.

[0018] Preferably, the filler is montmorillonite.

[0019] By adopting the above technical solution and specifically selecting montmorillonite, the airtightness of the protective layer formed by the protective liquid is further improved under the action of the filler, resulting in steel pipes with better corrosion resistance.

[0020] Preferably, the coupling agent is a silane coupling agent.

[0021] By adopting the above technical solutions and specifically selecting silane coupling agents, the dispersion stability of montmorillonite can be effectively improved, the effect of fillers in improving the airtightness of the protective layer can be better utilized, and the corrosion resistance of the steel pipe can be improved.

[0022] Secondly, this application provides a lightweight, high-strength seamless steel pipe for fitness equipment, employing the following technical solution: A lightweight, high-strength seamless steel pipe for fitness equipment is manufactured using the aforementioned production process for lightweight, high-strength seamless steel pipes for fitness equipment.

[0023] By adopting the above technical solution, the lightweight, high-strength seamless steel pipes used for fitness equipment have high strength, which can well meet the safety requirements of fitness equipment. They are also lightweight, which can well meet the portability requirements of fitness equipment. Furthermore, they have good corrosion resistance and are not prone to corrosion that leads to a decrease in strength. The resulting fitness equipment can better improve its safety and stability and has broad application prospects.

[0024] In summary, this application has the following beneficial effects: 1. Because this application adds a modifier composed of guar gum, guar gum, and jujube gum to the protective liquid, and combines it with the heating and heat preservation process in step 4, the gel structure formed by the modifier and the structure of the acrylic resin complement each other, which can significantly improve the airtightness of the protective layer, better block water vapor and oxygen, and thus make the protection of the steel pipe better, significantly improve the corrosion resistance, make the seamless steel pipe less prone to corrosion and strength reduction, and have higher safety and stability, thus better meeting the needs of fitness equipment.

[0025] 2. In this application, normalizing treatment is preferred, which can effectively refine the grains and eliminate the internal stress generated during the thinning and forming process, thereby simultaneously improving the dimensional stability, bending strength and stress corrosion resistance of the steel pipe, resulting in higher quality steel pipe.

[0026] 3. In this application, the preferred method is to select the specific mass ratio of guar gum, guar gum, and jujube gum so that the protective layer formed by the protective liquid can better protect the steel pipe, has better corrosion resistance, and the quality of the steel pipe is more stable. Detailed Implementation

[0027] The present application will be further described in detail below with reference to the embodiments.

[0028] Example 1

[0029] A manufacturing process for lightweight, high-strength seamless steel pipes used in fitness equipment includes the following steps: Step 1): Heat the high-strength low-alloy steel pipe to 800℃, hold for 3 minutes, then cool to 100℃ at a rate of 20℃ / min, and then allow it to cool naturally to obtain the pretreated steel pipe.

[0030] Step 2) Polish the pretreated steel pipe to a mirror finish until the Ra value is ≤0.05μm to obtain a polished steel pipe.

[0031] Step 3) Spray a protective liquid onto the surface of the polished steel pipe at a rate of 0.15 kg / m. 2 After being ventilated and dried for 7 days, the steel pipes are protected.

[0032] Step 4) Heat the pre-protected steel pipe to 100℃, hold for 20 minutes, and let it cool naturally to obtain a lightweight, high-strength seamless steel pipe for use in fitness equipment.

[0033] The high-strength low-alloy steel pipe is sourced from commercially available products and is a Q345B steel pipe.

[0034] The protective solution was prepared in-house, and the preparation method is as follows: 36.64 kg of deionized water, 43 kg of waterborne acrylic resin, 2.8 kg of propylene glycol phenyl ether, 11 kg of montmorillonite, 0.12 kg of silane coupling agent, 0.4 kg of defoamer, 0.8 kg of dispersant, 0.1 kg of wetting agent, 0.1 kg of pH adjuster, 4.2 kg of guar gum, 0.42 kg of guar gum, and 0.42 kg of jujube gum were added to a mixing tank, kept at a constant temperature of 60-65℃, and stirred at 60 r / min for 15 min to obtain a protective solution.

[0035] The protective solution should be kept at 60-65℃ during use.

[0036] The water-based acrylic resin was purchased from Dongguan Jincai Waterborne Materials Co., Ltd., model: AR610.

[0037] Propylene glycol phenyl ether was purchased from Shandong Shengrui Chemical Technology Co., Ltd., with an active ingredient content of 99%.

[0038] Montmorillonite was purchased from Hebei Hengguang Mineral Products Co., Ltd., 300 mesh, sodium-based montmorillonite.

[0039] The silane coupling agent was purchased from Yunsheng Chemical (Shandong) Co., Ltd., KH550.

[0040] The defoamer was purchased from Jinan Xinglongda Chemical Co., Ltd., model: XLLD-678.

[0041] The dispersant was purchased from Wuhan Runxingyuan Technology Co., Ltd., model: QSC-5040.

[0042] The wetting agent was purchased from Guangzhou Taili Chemical Co., Ltd., model: X-405.

[0043] The pH adjuster was AMP-95, purchased from Henan Cangyu Huashu Fine Chemical Co., Ltd.

[0044] Kederan gum was purchased from Shandong Guante Bioengineering Co., Ltd.

[0045] The guar gum was purchased from Jiangsu Caiwei Biotechnology Co., Ltd.

[0046] The jujube gum was purchased from Qingdao Tengyun Chemical Technology Co., Ltd.

[0047] Example 2

[0048] A manufacturing process for lightweight, high-strength seamless steel pipes used in fitness equipment includes the following steps: Step 1): Heat the high-strength low-alloy steel pipe to 800℃, hold for 3 minutes, then cool to 100℃ at a rate of 20℃ / min, and then allow it to cool naturally to obtain the pretreated steel pipe.

[0049] Step 2) Polish the pretreated steel pipe to a mirror finish until the Ra value is ≤0.05μm to obtain a polished steel pipe.

[0050] Step 3) Spray a protective liquid onto the surface of the polished steel pipe at a rate of 0.15 kg / m. 2 After being ventilated and dried for 7 days, the steel pipes are protected.

[0051] Step 4) Heat the pre-protected steel pipe to 100℃, hold for 25 minutes, and let it cool naturally to obtain a lightweight, high-strength seamless steel pipe for use in fitness equipment.

[0052] The high-strength low-alloy steel pipe is sourced from commercially available products and is a Q345B steel pipe.

[0053] The protective solution was prepared in-house, and the preparation method is as follows: Add 32.55 kg of deionized water, 45 kg of waterborne acrylic resin, 3 kg of propylene glycol phenyl ether, 12 kg of montmorillonite, 0.15 kg of silane coupling agent, 0.5 kg of defoamer, 1 kg of dispersant, 0.2 kg of wetting agent, 0.2 kg of pH adjuster, 4.5 kg of guar gum, 0.45 kg of guar gum, and 0.45 kg of jujube gum to a mixing tank, maintain a constant temperature of 60-65℃, and stir at 60 r / min for 15 min to obtain a protective solution.

[0054] The protective solution should be kept at 60-65℃ during use.

[0055] The water-based acrylic resin was purchased from Dongguan Jincai Waterborne Materials Co., Ltd., model: AR610.

[0056] Propylene glycol phenyl ether was purchased from Shandong Shengrui Chemical Technology Co., Ltd., with an active ingredient content of 99%.

[0057] Montmorillonite was purchased from Hebei Hengguang Mineral Products Co., Ltd., 300 mesh, sodium-based montmorillonite.

[0058] The silane coupling agent was purchased from Yunsheng Chemical (Shandong) Co., Ltd., KH550.

[0059] The defoamer was purchased from Jinan Xinglongda Chemical Co., Ltd., model: XLLD-678.

[0060] The dispersant was purchased from Wuhan Runxingyuan Technology Co., Ltd., model: QSC-5040.

[0061] The wetting agent was purchased from Guangzhou Taili Chemical Co., Ltd., model: X-405.

[0062] The pH adjuster was AMP-95, purchased from Henan Cangyu Huashu Fine Chemical Co., Ltd.

[0063] Kederan gum was purchased from Shandong Guante Bioengineering Co., Ltd.

[0064] The guar gum was purchased from Jiangsu Caiwei Biotechnology Co., Ltd.

[0065] The jujube gum was purchased from Qingdao Tengyun Chemical Technology Co., Ltd.

[0066] Example 3

[0067] A manufacturing process for lightweight, high-strength seamless steel pipes used in fitness equipment includes the following steps: Step 1): Heat the high-strength low-alloy steel pipe to 800℃, hold for 3 minutes, then cool to 100℃ at a rate of 20℃ / min, and then allow it to cool naturally to obtain the pretreated steel pipe.

[0068] Step 2) Polish the pretreated steel pipe to a mirror finish until the Ra value is ≤0.05μm to obtain a polished steel pipe.

[0069] Step 3) Spray a protective liquid onto the surface of the polished steel pipe at a rate of 0.15 kg / m. 2 After being ventilated and dried for 7 days, the steel pipes are protected.

[0070] Step 4) Heat the pre-protected steel pipe to 105℃, hold for 30 minutes, and let it cool naturally to obtain a lightweight, high-strength seamless steel pipe for use in fitness equipment.

[0071] The high-strength low-alloy steel pipe is sourced from commercially available products and is a Q345B steel pipe.

[0072] The protective solution was prepared in-house, and the preparation method is as follows: 28.46 kg of deionized water, 47 kg of waterborne acrylic resin, 3.2 kg of propylene glycol phenyl ether, 13 kg of montmorillonite, 0.18 kg of silane coupling agent, 0.6 kg of defoamer, 1.2 kg of dispersant, 0.3 kg of wetting agent, 0.3 kg of pH adjuster, 4.8 kg of guar gum, 0.48 kg of guar gum, and 0.48 kg of jujube gum were added to a mixing tank, kept at a constant temperature of 60-65℃, and stirred at 60 r / min for 15 min to obtain a protective solution.

[0073] The protective solution should be kept at 60-65℃ during use.

[0074] The water-based acrylic resin was purchased from Dongguan Jincai Waterborne Materials Co., Ltd., model: AR610.

[0075] Propylene glycol phenyl ether was purchased from Shandong Shengrui Chemical Technology Co., Ltd., with an active ingredient content of 99%.

[0076] Montmorillonite was purchased from Hebei Hengguang Mineral Products Co., Ltd., 300 mesh, sodium-based montmorillonite.

[0077] The silane coupling agent was purchased from Yunsheng Chemical (Shandong) Co., Ltd., KH550.

[0078] The defoamer was purchased from Jinan Xinglongda Chemical Co., Ltd., model: XLLD-678.

[0079] The dispersant was purchased from Wuhan Runxingyuan Technology Co., Ltd., model: QSC-5040.

[0080] The wetting agent was purchased from Guangzhou Taili Chemical Co., Ltd., model: X-405.

[0081] The pH adjuster was AMP-95, purchased from Henan Cangyu Huashu Fine Chemical Co., Ltd.

[0082] Kederan gum was purchased from Shandong Guante Bioengineering Co., Ltd.

[0083] The guar gum was purchased from Jiangsu Caiwei Biotechnology Co., Ltd.

[0084] The jujube gum was purchased from Qingdao Tengyun Chemical Technology Co., Ltd.

[0085] Comparative Example 1 A manufacturing process for lightweight, high-strength seamless steel pipes used in fitness equipment differs from Example 2 only in that: In the protective solution, xanthan gum is used to replace kerogen gum in an equal amount.

[0086] Xanthan gum was purchased from Henan Angshe Chemical Technology Co., Ltd.

[0087] Comparative Example 2 A manufacturing process for lightweight, high-strength seamless steel pipes used in fitness equipment differs from Example 2 only in that: In the protective solution, tara gum was used to replace guar gum in an equal amount.

[0088] Tara gum was purchased from Chongqing Tianrun Biological Products Co., Ltd.

[0089] Comparative Example 3 A manufacturing process for lightweight, high-strength seamless steel pipes used in fitness equipment differs from Example 2 only in that: In the protective solution, astragalus gum was used to replace jujube gum in an equal amount.

[0090] Astragalus gum was purchased from Henan Linbang Biotechnology Co., Ltd.

[0091] Comparative Example 4 A manufacturing process for lightweight, high-strength seamless steel pipes used in fitness equipment differs from Example 2 only in that: In the protective solution, xanthan gum was used to replace guar gum in equal amounts, tara gum was used to replace guar gum in equal amounts, and astragalus gum was used to replace jujube gum in equal amounts.

[0092] Xanthan gum was purchased from Henan Angshe Chemical Technology Co., Ltd.

[0093] Tara gum was purchased from Chongqing Tianrun Biological Products Co., Ltd.

[0094] Astragalus gum was purchased from Henan Linbang Biotechnology Co., Ltd.

[0095] Experiment 1 The seamless steel pipes prepared in each embodiment and comparative example were placed in an environment with a constant temperature of 50°C and a relative humidity of 95% for 10 days. The observation and recording of whether the seamless steel pipes showed signs of corrosion were recorded. The specific experimental data are detailed in Table 1.

[0096] Table 1

[0097] According to Table 1, the addition of guar gum, guar gum, and jujube gum in each embodiment can effectively improve the structure of acrylic resin, resulting in higher airtightness of the protective layer formed by the protective liquid and a more significant improvement in the anti-rust effect.

[0098] Comparative Examples 1 and 4 used xanthan gum instead of guar gum, which prevented the formation of thermally irreversible gel in the protective layer. This resulted in a lack of improvement in the protective layer's effectiveness and a significant decrease in its anti-corrosion effect. In Comparative Examples 2 and 3, guar gum was retained, which allowed the formation of thermally irreversible gel in the protective layer. However, due to the replacement of guar gum and jujube gum, the structure of the thermally irreversible gel formed by guar gum was altered, which reduced the effect of improving airtightness. Therefore, the anti-corrosion effect was somewhat lower than that of the examples.

[0099] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A manufacturing process for lightweight, high-strength seamless steel pipes used in fitness equipment, characterized in that: Includes the following steps: Step 1) The high-strength low-alloy steel pipe is normalized to obtain a pretreated steel pipe; Step 2) Polish the surface of the pretreated steel pipe to obtain a polished steel pipe; Step 3) Spray a protective liquid onto the surface of the polished steel pipe and let it dry to obtain a pre-protected steel pipe; Step 4) Heat the pre-protected steel pipe to 100-105℃, hold for 20-30 minutes, and let it cool naturally to obtain a lightweight, high-strength seamless steel pipe for fitness equipment. The protective liquid comprises the following components in parts by weight: Solvent: 28.46-36.64 parts; 43-47 parts of water-based acrylic resin; Film-forming aid 2.8-3.2 parts; 11-13 parts of filler; 0.12-0.18 parts of coupling agent; Processing aids: 1.4-2.4 parts; Modifier 5.04-5.76 parts; The modifier is a compound of guar gum, guar gum, and jujube gum.

2. The manufacturing process of a lightweight, high-strength seamless steel pipe for fitness equipment according to claim 1, characterized in that: The mass ratio of guar gum, guar gum, and jujube gum in the modifier is 4.2-4.8:0.42-0.48:0.42-0.

48.

3. The manufacturing process of a lightweight, high-strength seamless steel pipe for fitness equipment according to claim 1, characterized in that: The processing aid is a compound of defoamer, dispersant, wetting agent and pH adjuster.

4. The manufacturing process of a lightweight, high-strength seamless steel pipe for fitness equipment according to claim 3, characterized in that: In the processing aids, the mass ratio of defoamer, dispersant, wetting agent, and pH adjuster is 0.4-0.6: 0.8-1.2: 0.1-0.3: 0.1-0.

3.

5. The manufacturing process of a lightweight, high-strength seamless steel pipe for fitness equipment according to claim 1, characterized in that: The film-forming aid is propylene glycol phenyl ether.

6. The manufacturing process of a lightweight, high-strength seamless steel pipe for fitness equipment according to claim 1, characterized in that: The filler material is montmorillonite.

7. The manufacturing process of a lightweight, high-strength seamless steel pipe for fitness equipment according to claim 6, characterized in that: The coupling agent is a silane coupling agent.

8. A lightweight, high-strength seamless steel pipe for use in fitness equipment, characterized in that: It is manufactured by the production process of lightweight, high-strength seamless steel pipe for fitness equipment as described in any one of claims 1-7.

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