Pinch roll bearing seat with prolonged service life

Abstract

The invention relates to a pinch roll bearing seat with prolonged service life, which is characterized in that a specific corrosion-resistant welding material is adopted to perform welding strengthening treatment on matched working surfaces such as a bore hole, a bottom surface and an end surface of the bearing seat, and the corrosion-resistant welding material comprises the following chemical components in percentage by weight: 13-18% of Cr, 4-8% of Ni, less than or equal to 3% of Mo, 0.05-0.15% of C and the balance of Fe and inevitable impurities. The specific corrosion-resistant welding wire is adopted for conducting welding strengthening treatment on the bore hole of the bearing seat and the matched working faces such as the bottom face and the end face, and the innovative technological method can essentially improve the corrosion resistance and the abrasion resistance of the bearing seat.

Description

Technical Field

[0001] The invention belongs to the technical field of pinch roller equipment of a coiling machine of a hot-rolled strip production line, and in particular relates to a pinch roller bearing seat with improved service life. Background Art

[0002] As key equipment for material transportation and processing in industrial production, pinch rollers are widely used in many industries such as steel, non-ferrous metal rolling, papermaking, printing, etc. As the core component of the pinch roller, the performance of the bearing seat is directly related to the working efficiency and service life of the pinch roller. Under actual working conditions, the bearing seat often faces extremely complex and harsh working environment. Taking the steel hot rolling production line as an example, the pinch roller bearing seat is in a high temperature (up to 50-150℃) and high humidity environment for a long time, and is also corroded by corrosive media such as cooling water and iron oxide. Therefore, a new bearing seat treatment method is urgently needed to achieve the purpose of increasing the service life of the pinch roller bearing seat. Summary of the invention

[0003] The purpose of the present invention is to provide a pinch roller bearing seat with a longer service life. By using specific corrosion-resistant welding wire to perform welding strengthening treatment on the matching working surfaces such as the bearing seat boring, bottom surface and end surface, this innovative process method will essentially improve the corrosion resistance and wear resistance of the bearing seat.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] A pinch roller bearing seat with improved service life, wherein a specific corrosion-resistant welding material is used to perform welding strengthening treatment on the matching working surfaces such as the bearing seat boring, bottom surface and end surface, wherein the chemical composition of the corrosion-resistant welding material includes, by weight percentage, Cr: 13% to 18%, Ni: 4% to 8%, Mo: ≤3%, C: 0.05% to 0.15%, and the rest is Fe and unavoidable impurities.

[0006] The matching working surfaces of the bearing seat include a boring hole, a bottom surface and an end surface of the bearing seat.

[0007] The welding layer of the welding strengthening treatment is 2 to 5 mm.

[0008] The welding strengthening treatment method includes: cleaning treatment of the welding surface before welding, argon mixed gas shielded welding, post-weld heat treatment and post-weld grinding (processing) treatment.

[0009] The welding voltage of the argon mixed gas shielded welding is 20-40V, the current is 150-300A, and the mixed gas flow rate is 5-10L / min.

[0010] The post-weld heat treatment temperature is 520-560° C. The heat treatment releases welding stress, improves the post-weld structure, and improves corrosion resistance and damage resistance.

[0011] Specifically, this special corrosion-resistant welding wire is made by scientifically matching and optimizing a variety of alloy elements. The various alloy elements in the welding wire, such as chromium (Cr), nickel (Ni), molybdenum (Mo), carbon (C), etc., play their own unique roles in the welding process. Chromium can form a stable solid solution structure with iron, greatly improving the strength and toughness of the weld metal. At the same time, after contacting with oxygen, a dense Cr2O3 oxide film is formed on the surface of the weld (layer), which effectively prevents the contact between the corrosive medium and the metal matrix, and significantly enhances the corrosion resistance. Nickel not only further improves the strength and toughness of the weld, but also improves the low-temperature performance of the weld, ensuring that the bearing seat can maintain good performance under different temperature environments. Molybdenum helps to improve the weld's resistance to pitting corrosion by corrosive ions such as chloride ions, further improving the overall corrosion resistance. Although the carbon content is relatively low, it plays an important role in regulating the hardness and strength of the weld, ensuring that the weld has a certain hardness without increasing brittleness due to excessive hardness, and is more suitable for use on the matching working surface of the pinch roller bearing seat, especially the boring position of the bearing seat.

[0012] The present invention ensures the welding quality through precise control of the welding process, including cleaning of the surface before welding, parameter setting during welding, and heat treatment and grinding (processing) after welding, so that the additive metal and the bearing seat substrate are firmly combined to form an excellent overall performance. The heat treatment temperature of the present invention can effectively eliminate the stress between the additive and the substrate to avoid cracking, and can refine the grain structure of the weld, effectively improve the strength, toughness and plasticity of the working surface of the pinch roller bearing seat, and enhance the corrosion resistance of the weld to form a more stable passivation film. The hardness, strength and wear resistance of the weld after heat treatment are also effectively improved, making it more suitable for withstanding high loads and wear environments. The heat treatment temperature of the present invention can also reduce dimensional changes after welding, ensure the dimensional stability of the workpiece, and ensure the precision use requirements of the bearing seat boring.

[0013] Through the above innovative process, the present invention is expected to significantly extend the overall service life of the pinch roller. From a practical application perspective, the extension of the service life of the pinch roller means a reduction in the frequency of equipment maintenance, which greatly reduces the maintenance workload and repair costs of the equipment. At the same time, due to the significant reduction in equipment downtime and maintenance time, the production line can maintain continuous and stable operation, effectively improving production efficiency, winning advantages for enterprises in market competition, and creating significant economic benefits.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1) Improve corrosion resistance: The metal of the welding strengthening treatment layer can form a dense protective barrier, effectively resist the erosion of corrosive media, and significantly extend the service life of the pinch roller bearing seat in harsh environments. According to tests, the pinch roller bearing seat treated with the technology of the present invention improves corrosion resistance by more than 15%.

[0016] 2) Enhanced wear resistance: The metal of the welding strengthening treatment layer has higher hardness and strength, and the microstructure is uniform and fine, which reduces local wear.

[0017] 3) Extend the service life of the pinch roller: The improvement of the corrosion resistance and wear resistance of the bearing seat significantly reduces the failure rate of the pinch roller, improves the assembly and preparation accuracy of the pinch roller, improves the winding accuracy and operation stability of the coiler, reduces the equipment maintenance frequency and maintenance costs, and improves production efficiency.

[0018] 4) The present invention uses a corrosion-resistant material additive manufacturing method to obtain a metal welding strengthening treatment layer for the mating working surfaces such as the bottom surface and the end surface of the bearing seat, so that the pinch roller bearing seat can resist the corrosion of substances such as cooling water during online use. It has excellent corrosion resistance and wear resistance, and can significantly extend the service life of the pinch roller bearing seat. The bearing seat boring hole uses a wear-resistant material additive manufacturing method to obtain a metal welding strengthening treatment layer to meet the online service life of the pinch roller bearing seat boring hole. After one year of use, the mating working surface of the pinch roller bearing seat of the present invention has no obvious signs of corrosion on the surface, and the maximum wear degree is no more than 1 / 6 of the welding strengthening treatment welding layer. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the welding layer of the pinch roller bearing seat matching working surface of the present invention.

[0020] In the figure: 1, boring strengthening layer; 2, end surface strengthening layer, 3, bottom surface strengthening layer. DETAILED DESCRIPTION

[0021] The present invention is described in detail below in conjunction with the accompanying drawings, but it should be noted that the implementation of the present invention is not limited to the following embodiments.

[0022] like Figure 1 As shown, a pinch roller bearing seat with improved service life is provided, wherein a specific corrosion-resistant welding material is used to perform welding strengthening treatment on the matching working surfaces such as the bearing seat bore, bottom surface and end surface, so as to obtain a bore strengthening layer 1, an end surface strengthening layer 2 and a bottom surface strengthening layer 3. The chemical composition of the corrosion-resistant welding material includes, by weight percentage: Cr: 13% to 18%, Ni: 4% to 8%, Mo: ≤3%, C: 0.05% to 0.15%, and the rest is Fe and unavoidable impurities.

[0023] The matching working surfaces of the bearing seat include a boring hole, a bottom surface and an end surface of the bearing seat.

[0024] The welding layer of the welding strengthening treatment is 2 to 5 mm.

[0025] The welding strengthening treatment method includes: cleaning treatment of the welding surface before welding, argon mixed gas shielded welding, post-weld heat treatment and post-weld grinding (processing) treatment.

[0026] The welding voltage of the argon mixed gas shielded welding is 20-40V, the current is 150-300A, and the mixed gas flow rate is 5-10L / min.

[0027] The post-weld heat treatment temperature is 520-560° C. The heat treatment releases welding stress, improves the post-weld structure, and improves corrosion resistance and damage resistance.

[0028] Embodiment 1:

[0029] Chemical composition design of welding materials: Cr: 17%, Ni: 7%, Mo: 2%, C: 0.10%, and the rest is Fe and unavoidable impurities.

[0030] Preparation before welding: Clean the bearing seat boring, bottom surface and end surface and other matching working surfaces, including chemical cleaning (using washing oil to remove oil stains) and mechanical grinding (remove rust, oxide scale, etc.) to ensure that the surface to be welded is smooth.

[0031] Welding process: Argon mixed gas shielded welding is used, the welding voltage is controlled at 25V, the current is controlled at 200A, and the mixed gas flow rate is controlled at 8L / min. The welding gun maintains a suitable angle with the welding surface, and moves the welding gun at a constant speed to ensure that the weld is uniform and full, and to avoid defects such as pores and slag inclusions.

[0032] Post-weld treatment: After welding, the weld is heat treated and machined to make it smoothly transition with the bearing seat bore and bottom surface. The thickness of the weld layer after processing reaches 4mm. The post-weld heat treatment temperature is 530℃. After one year of use, there is no obvious corrosion on the mating working surface of this embodiment, and the maximum wear degree is no more than 0.5mm.

[0033] Embodiment 2:

[0034] Chemical composition design of welding materials: Cr: 14%, Ni: 5%, Mo: 1%, C: 0.06%, and the rest is Fe and unavoidable impurities.

[0035] Preparation before welding: Clean the bearing seat boring, bottom surface and end surface and other matching working surfaces, including chemical cleaning (using washing oil to remove oil stains) and mechanical grinding (remove rust, oxide scale, etc.) to ensure that the surface to be welded is smooth.

[0036] Welding process: Argon mixed gas shielded welding is used, the welding voltage is controlled at 27V, the current is controlled at 250A, and the mixed gas flow rate is controlled at 9L / min. The welding gun maintains a suitable angle with the welding surface, and moves the welding gun at a constant speed to ensure that the weld is uniform and full, and to avoid defects such as pores and slag inclusions.

[0037] Post-weld treatment: After welding, the weld is heat treated and machined to make it smoothly transition with the inner hole and bottom surface of the bearing seat. The thickness of the weld layer after processing reaches 3mm. The post-weld heat treatment temperature is 540℃. After one year of use, there is no obvious corrosion on the mating working surface of this embodiment, and the maximum wear degree is no more than 0.5mm.

[0038] Embodiment 3:

[0039] Chemical composition design of welding materials: Cr: 15%, Ni: 6%, Mo: 1.5%, C: 0.12%, and the rest is Fe and unavoidable impurities.

[0040] Preparation before welding: Clean the bearing seat boring, bottom surface and end surface and other matching working surfaces, including chemical cleaning (using washing oil to remove oil stains) and mechanical grinding (remove rust, oxide scale, etc.) to ensure that the surface to be welded is smooth.

[0041] Welding process: Argon mixed gas shielded welding is used, the welding voltage is controlled at 30V, the current is controlled at 280A, and the mixed gas flow rate is controlled at 10L / min. The welding gun maintains a suitable angle with the welding surface, and moves the welding gun at a constant speed to ensure that the weld is uniform and full, and to avoid defects such as pores and slag inclusions.

[0042] Post-weld treatment: After welding, the weld is heat treated and machined to make it smoothly transition with the inner hole and bottom surface of the bearing seat. The thickness of the weld layer after processing reaches 4mm. The post-weld heat treatment temperature is 550℃. After one year of use, there is no obvious corrosion on the mating working surface of this embodiment, and the maximum wear degree is no more than 0.6mm.

[0043] Embodiment 4:

[0044] Chemical composition design of welding materials: Cr: 16%, Ni: 6%, Mo: 2.6%, C: 0.08%, and the rest is Fe and unavoidable impurities.

[0045] Preparation before welding: Clean the bearing seat boring, bottom surface and end surface and other matching working surfaces, including chemical cleaning (using washing oil to remove oil stains) and mechanical grinding (remove rust, oxide scale, etc.) to ensure that the surface to be welded is smooth.

[0046] Welding process: Argon mixed gas shielded welding is used, the welding voltage is controlled at 25V, the current is controlled at 220A, and the mixed gas flow rate is controlled at 7L / min. The welding gun maintains a suitable angle with the welding surface, and moves the welding gun at a constant speed to ensure that the weld is uniform and full, and to avoid defects such as pores and slag inclusions.

[0047] Post-weld treatment: After welding, the weld is heat treated and machined to make it smoothly transition with the inner hole and bottom surface of the bearing seat. The thickness of the weld layer after processing reaches 5mm. The post-weld heat treatment temperature is 520℃. After one year of use, there is no obvious corrosion on the mating working surface of this embodiment, and the maximum wear degree is no more than 0.6mm.

[0048] This bearing seat has unique technological features. In order to extend the online use time of the pinch roller bearing seat boring, the boring part is additively manufactured using wear-resistant materials. This wear-resistant material can effectively improve the wear resistance of the boring hole and reduce wear and loss during use. At the same time, corrosion-resistant materials are used to implement additive manufacturing for the mating working surfaces such as the bottom and end faces of the bearing seat. Since the mating working surfaces such as the bottom and end faces of the pinch roller bearing seat are often in contact with corrosive substances such as cooling water during the online use of the pinch roller bearing seat, the additive manufacturing of corrosion-resistant materials can enhance its corrosion resistance, thereby improving the overall service life and performance of the bearing seat. The service life is extended by 2-4 years compared to conventional pinch roller bearing seats.

Claims

1. A pinch roller bearing seat with improved service life, characterized in that: The corrosion-resistant welding material is used to perform welding strengthening treatment on the matching working surface of the bearing seat. The chemical composition of the corrosion-resistant welding material includes, by weight percentage: Cr: 13% to 18%, Ni: 4% to 8%, Mo: ≤3%, C: 0.05% to 0.15%, and the rest is Fe and unavoidable impurities.

2. A pinch roller bearing seat with improved service life according to claim 1, characterized in that: The matching working surfaces of the bearing seat include a boring hole, a bottom surface and an end surface of the bearing seat.

3. A pinch roller bearing seat with improved service life according to claim 1, characterized in that: The welding layer of the welding strengthening treatment is 2 to 5 mm.

4. A pinch roller bearing seat with improved service life according to claim 1, characterized in that: The welding strengthening treatment method comprises: cleaning treatment of the welding surface before welding, argon mixed gas shielded welding, post-weld heat treatment and post-weld grinding treatment.

5. A pinch roller bearing seat with improved service life according to claim 4, characterized in that: The welding voltage of the argon mixed gas shielded welding is 20-40V, the current is 150-300A, and the mixed gas flow rate is 5-10L / min.

6. A pinch roller bearing seat with improved service life according to claim 4 or 5, characterized in that: The post-weld heat treatment temperature is 520-560°C.

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