Sundwig SPM and temper mills
Fine in shape
Skin pass mills and temper mills improve the mechanical material properties, surface characteristics, and strip quality for a wide range of strip widths.
Skin passing is characterized by a small strip elongation process of between 0.2 and 3.0%, but temper rolling provides greater elongation of up to 12%. A positive effect is achieved in the mechanical strip properties as a result of strip elongation.
One operation targeted by skin passing is to secure the quality in the deep-drawing process by avoiding so-called Luder lines caused by plastic deformation and thus obtain perfect strip quality without imperfections from deep drawing. This operation is particularly important for materials with pronounced yield strengths.
At the same time, the skin pass operation corrects the flatness defects caused by preceding processes.
The work rolls provide the strip surface with the desired surface quality for a long lifetime as well as high gloss or, in particular, roughness and peaks per unit of length. The customer-defined strip surface roughness during the final strip rolling process ensures that subsequent processes, like deep drawing or painting, also meet the requirements.
Skin pass or temper mills can be designed with a pay-off and re-coiler group, a centering device, entry and exit bridles for tension adjustment, anti-flutter and anti-crimping rolls, respectively, a 2-high or 4-high mill stand with quick roll changing, bending blocks, automatic pass line adjustment, fully hydraulic screw-down cylinder system, and a state-of-the-art control system with an advanced process model. Skin passing or temper rolling can be performed in dry or wet operating mode.
With more than 50 references for skin pass and temper mills in 2-high or 4-high design – inline or offline, Sundwig is one of the most notable suppliers in this rolling mill technology Segment.
Offline Skin Pass Mills
Inline Skin Pass Mills
Strengths and benefits
Positive and negative work roll bending, secured to the mill
Roll shifting arrangement (push/pull), secured to the mill
Infinitely variable pass line adjustment
Twin drive system
High-pressure roll cleaning system for wet skin passing
Deformation-optimized housing geometry
Pre-commissioning at ANDRITZ Sundwig Workshops
Corresponding E&A models
- Strip elongation and flatness control
- Advanced roll force model
- Strip flatness model
- Pass scheduling program with roll profile modeling and: gap calculation method
- Long-term pass schedule and mill pre-set optimization program