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• Release time：2025-09-07 08:00
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【概要描述】The Impact of Degreasing and Cleaning Units on Second-Hand Cold Rolling Mills Degreasing and cleaning units are essential post-rolling components in second-hand cold rolling mills, removing rolling oil, metal fines, and contaminants from the strip surface. Their effectiveness directly influences downstream processing (e.g., annealing, coating) and final product quality.​ Surface Cleanliness Assurance​ In second-hand cold rolling mills, modern degreasing units use a combination of alkaline cleaning solutions (pH 10-12) and high-pressure water jets (1-3 MPa) to achieve surface oil residues ≤5mg/m²—meeting the strict requirements of automotive coating lines (e.g., BMW GS 90011). For electrical steel strips used in transformers, this level of cleanliness ensures optimal insulation performance (reducing eddy current losses by 10-15%). Older cleaning units in unrefurbished second-hand mills may leave oil residues of 20-30mg/m², causing coating adhesion failures or annealing defects.​ Downstream Process Compatibility​ Clean strip surfaces from well-maintained degreasing units in second-hand cold rolling mills eliminate the need for pre-treatment rework in downstream processes. For example, cold-rolled strips destined for galvanizing require oil-free surfaces to ensure uniform zinc adhesion; a reliable cleaning unit reduces galvanizing defect rates by 45-55%. Additionally, the unit’s drying section (using hot air at 80-120°C) prevents water spots, which can cause rust formation during storage—critical for carbon steel strips with no protective coating.​ Chemical and Water Efficiency​ Refurbished degreasing units in second-hand cold rolling mills feature closed-loop chemical recycling systems, reducing cleaning solution consumption by 60-70% (from 5L/ton to 1.5-2L/ton of steel). Water recycling units further lower fresh water usage by 80%, aligning with environmental standards such as ISO 14001. For second-hand mills with open-loop systems, upgrading to closed-loop technology can cut annual water and chemical costs by ​ 15,000− 25,000.​ Maintenance and Optimization Strategies​ To ensure the effectiveness of degreasing and cleaning units in second-hand cold rolling mills:​ Monitor cleaning solution concentration daily; adjust by adding chemicals if concentration drops below 5% (by volume).​ Inspect high-pressure nozzles weekly for clogging; replace nozzles with flow rate deviations exceeding 10%.​ Clean the filtration system (5-10μm filters) monthly to remove metal fines and sludge.​ Replace heating elements in the drying section quarterly if surface temperature falls below 80°C.​ For second-hand cold rolling mills processing high-strength steel strips (≥800 MPa), adding a brush cleaning stage before chemical degreasing can remove tough rolling oil residues, further improving surface cleanliness by 20-30%.​ For more information, please pay attention to the website of Jinyujie Mechanical and Electrical Used Pipe Mill Supplier：www.usedpipemill.com​