Pickling Line

Wastage in down-stream rolling and coating processes is reduced significantly if the metal surface is completely free from surface impurities such as scale, oil and grease. The cleaner the material at the beginning of the cold rolling process is, the more reliable and cost-effective the production of the required finished quality. Fast, effective pickling is the prerequisite to achieve this goal. This, in turn, requires a stable process, exact strip tracking and accurate strip and pickling control.

Siemens VAI supplies the full range of technological solutions for the descaling of both strip and wire-rod. Pickling lines supplied by us are characterized by high pickling rates, low-cost pickling operations, flexible production a wide range of product sizes, qualities and coil weights, reliable plant operation, low maintenance requirements in addition to the fulfillment of the highest standards for environmental safety.

Pickling Technology for strip includes Push-Pull- and Continuous Pickling lines, the latter either standalone or coupled to a tandem cold mill. Siemens VAI is able to offer the whole range of mechatronic packages available for Pickling lines.

The scope of Siemens VAI descaling/pickling technology and equipment includes

• Continuous Pickling Lines
• Combined Pickling Lines and Tandem Cold Mills
• Combined Pickling and Temper Rolling Lines
• Combined Pickling and Galvanizing Lines
• Push-Pull Pickling Lines

Special packages within these lines include

• Flash Butt, Mash Lap, and Laser Welders
• Scale Breaker / Tension leveler
• Shallow-type, turbulent acid pickling tanks technology
• Turret-type Side-Trimmer with dynamic width adjustment
• Scrap-Chopper, single or double
• Inline automatic surface inspection system SIAS
• Automatic process control FAPLAC®
• Modern drive controls and automation systems
• Skin Pass / Temper Mill

Continuous Pickling Lines

Continuous pickling lines supplied by Siemens VAI feature modular design, high pickling efficiency, economical operation and the application of advanced technologies such as turbulence pickling. Selection and integration of all process equipment and components is accomplished on the basis of our own in-house operational experience. In this way, our strongest customers' demands can be met, as well as the latest environment standards.

Special features are

• Shallow tank design
• Turbulent pickling
• Side jet with counterflow design
• Adjustable flow pumps
• Adjustable bath depth level
• No contact between strip and any fixed part, hence scratch-free processing
• Conventional or polypropylene tank
• Counterflow cascade Rinse section
• FAPLAC (Fully automatic pickling liquor analysis and control)
• Mathematical model for optimum process setup and control
• High Pressure Rinse: 20 bar at the last spray header significantly improves the strip cleanliness
• Closed-circulation loops for acid, fume and rinse water reduce the costs for environmental-friendly operation
• Full fume exhaust control and cleaning
  
  

Main Benefits

• Highest pickling throughput rates
• Uniformly pickled surfaces
• Low operating cost
• Low utility consumption
• Flexible processing of a wide range of strip dimensions and grades
• Reliable, robust and low-maintenance equipment
• Use of computer simulations and in-house experimental facilities for determining optimum plant parameters
• Lowest water consumption

Push-Pull Pickling Lines

For the pickling of non-weldable materials and heavy-gauge strips, Siemens VAI offers lines of discontinuous type. Push-pull pickling lines offer significant advantages with respect to investment costs and operational flexibility, particularly for frequently changing strip dimensions and steel grades. Siemens VAI offers a uniquely designed V-shaped flat pickling tank, which increases the strip stiffness during its passage through the tank. Strip buckling and flattering is avoided and reliable threading is ensured.

In order to prevent strip from staining in the rinsing section, Siemens VAI has developed a special anti-stain system which does not require chemical additives.

The energy-efficient design of the fume-extraction and sealing system significantly reduces energy costs and acid losses.

Main Benefits

• Compact, "flat-floor" design of the line
• Ability to process a wide range of strip thicknesses, up to 16 mm
• Ability to process high yield strength materials, as much as 1,000 MPa
• Reliable strip threading thanks to unique design of tanks' inside
• Homogeneous descaling of strip
• Reduction of steam consumption by approx. 20%
• No strip staining during short line standstill
• Possibility to implement Skin-Pass Mill or SIAS