The full range of pickling solutions for effective removal of mill scale and other surface impurities
As a market leader, John Cockerill supplies the full range of pickling solutions for both flat and long products, ensuring the effective removal of mill scale and other surface impurities from hot and cold rolled stainless steel, carbon steel or silicon steel, to non-ferrous metal strip such as aluminum, brass, etc. The resulting scale-free quality of the pickled strip improves the quality of the downstream rolling and coating processes.
Used for processing individual coils without strip joining, John Cockerills push pull pickling lines are ensuring excellent operational flexibility in the face of frequently changing strip dimensions and steel grades, and also non-weldable material. Their specific design makes such lines the only practical way of descaling heavy gauge coiled product.
John Cockerills unique v-shaped tank profile facilitates threading the strip through the pickling tank. The fact that there is no strip accumulator in the line makes this technology easy to operate and the most cost-effective method of hot band finishing. Applications range from the typical service center to the high production requirements of the largest mini mills.
Semi-Continuous- and Continuous Pickling Lines are used for high capacity production with continuous operation by stitching or welding. The strip accumulators, also called loopers, provided at the entry and exit sections of the line ensure a consistent product flow during joining, coiling and removal of the steel coils.
In continuous pickling, the line runs at constant speed, while in the Semi-Continuous Line the speed of the strip is reduced during changeover or coil joining, due to the lower capacity of the loopers. The installation of Semi-Continuous Lines is highly cost-effective due to the simpler looper design, while Continuous Pickling Lines provide the highest production capacity.
John Cockerills high turbulence pickling tank technology for continuous pickling lines is currently among the most efficient and also the most cost effective solutions on the market. In order to most effectively cover all types of applications and product mixes, these pickling tanks come in a range of profiles and acid injection systems, including the latest John Cockerill development, spray pickling modules (see page 11). Accurate strip and pickling process control optimizes scale removal without over-pickling. John Cockerills Pickling Process Management (PPM) system, together with its fully automated acid control management system, ensures the environmentally safe operation of the plant.
In stainless steel pickling applications, John Cockerills Neolyte Purification Systems not only reduce harmful chromium (+6) to non-toxic chromium (+3), but also regenerate the electrolyte, thus reducing operating costs and the environmental impact of such lines, while fumes loaded with Nox produced during stainless steel pickling, are most efficiently treated in John Cockerills latest generation of Selective Catalytic Reactors (SCR-Technology).
Pickling lines for long products are a highly specialized group of batch treatment lines, designed according to the product shape, process required and unique parameters defined by the client. John Cockerills new generation plants feature automated processing using a Level II or Level III control system, multiple fill-drain cycles via an independent transportation function, cascade rinsing using spray and immersion, waste air and waste water treatment aimed at minimizing emissions, and acid control, as well as management through recovery or regeneration processes.
Along with high turbulence pickling that ensures uniform pickling conditions and high heat transfer rates, John Cockerill uses hook vibration for uniform pickling and a high pressure spray rinse arrangement that guarantees a clean surface without residual contamination.
Pickling Line Designs:
• Push Pull or Semi-Continuous Push Pull Pickling Lines
• Continuous Pickling Lines
For carbon steel, including silicon steel Continuous Pickling Lines (CPL) can be part of combined lines:
• Tandem Cold Mills (PLTCM)
• Annealing Lines for Silicon Steel
For stainless steel a CPL is incorporated into:
• Hot Strip Annealing and Pickling Lines (HAPL)
• Cold Strip Annealing and Pickling Lines (CAPL)
• Combined Hot/ Cold Strip Annealing Lines (H/CAPL)
• Direct Roll Annealing Pickling Lines (DRAP)
Batch pickling plants for ferrous and non-ferrous metals:
• Wire Coil Pickling Lines
• Tube Pickling Lines
• Bar Pickling Lines
• Plate Pickling Lines
• Universal Pickling Lines
• Highest product quality through uniformly pickled surface
• Highest achievable production rates
• Optimized pickling parameters through mathematical modelling
• Low operating costs with controlled utility consumption
• Environmentally friendly operation
• Low maintenance costs
• Closed loop systems for acid, water and air treatment