A method for manufacturing a shot-blasted textured chromium-plated work roll for a cold rolling temper mill
A textured chromium-plated work roll for a cold rolling temper mill, belonging to the technical field of conductive rolls for electroplating operations in cold rolling temper mills.
[Background Technology]
[0002] With the rapid development of industries such as automotive and home appliances, users' requirements for the surface quality and performance of strip steel have been continuously increasing. The demand for high-quality cold-rolled strip steel has risen year by year, driving the rapid development of roll surface texturing technology. The basic parameters of strip steel surface morphology are roughness and Pc value. Uniformly distributed roughness, high Pc value, and irregularly distributed morphology can reduce optical interference fringes, avoid orange peel effects, and improve the paint optical properties of the strip steel. Therefore, roughness and Pc value are key factors in controlling the performance of strip steel, and different cold-rolled plates have different control standards for roughness and Pc value.
[0003] As consumable components in steel production, rolls transfer the surface morphology of strip steel through a decaying copying process. The quality of the rolls directly affects the quality of the strip steel. Currently, to control and adjust the surface morphology of finished strip steel, work rolls in cold rolling temper mills or skin pass mills, as well as work rolls in the last stand of finishing mills, are all textured rolls. The surface morphology of strip steel is primarily formed through secondary transfer from textured rolls, and the surface morphology of the textured rolls in the final stand plays a decisive role in the strip steel's surface morphology. Therefore, researching textured chromium-plated work rolls has significant practical value for improving the quality of cold-rolled plates, reducing roll consumption, and increasing mill operating efficiency.
[0004] Since electroplating is a process with replication characteristics, meaning the morphology of the substrate directly determines the morphology after electroplating, high-quality texturing technology directly determines the product quality of cold rolling work rolls. The texturing of cold rolling work rolls includes two methods: shot blasting texturing and electrical discharge texturing (EDT). The EDT process forms concave textured morphology on the roll surface through local melting of the roll surface material. However, EDT has high costs and high equipment investment, with the texturing cost for a single work roll being approximately 4000 yuan, and it is only used in very large steel mills. The shot blasting texturing process uses compressed air to spray irregular steel shots onto the roll surface, creating unevenness through plastic deformation of the roll surface. The microscopic morphology of the roll surface consists of many sharp peaks that are prone to breakage and wear. After electroplating, the chromium coating covers the roll surface but still retains the original sharp peak state of the textured roll surface. During use, the sharp peak areas on the roll surface are prone to breakage and wear quickly, resulting in poor roughness retention and wear resistance, leading to a short service life. Therefore, shot-blasted textured rolls usually undergo a peak-shaving process before electroplating to remove burrs, followed by electroplating, making the process relatively complex. Moreover, since the surface material of the work roll is forged steel with a surface hardness of about 800 HV, the shot blasting texturing process struggles to form a surface morphology with high peak density on such high-hardness forged steel surfaces, making it difficult to further improve the surface quality of the strip steel.
2024-07-31
Leveling machine shot blasting texturing chrome-plated work roll
×