Where the
world gathers for metal finishing
Q&As since 1989


-----

Quality Policy/Surface Defect Catalog

2001

Dear Readers,

I am working with Pakistan Steel and my assigned job is that to improve the quality of cold rolled and Zn coated steel sheet.

We have various plants like Continuous Pickling Unit, Reversible Rolling Mill, Annealing Unit, Temper Rolling Mill, Cold Shearing Unit , Cold Slitting Unit, Section Forming Unit and Hot-Dip Galvanizing (continuous process).

We are facing some problems regarding surface quality i.e. Buckles and Edge Wave during reversible and temper rolling. Please tell me how we can control Buckles and Edge Wave.

We are also facing problems at hot-dip galvanizing (continuous process) regarding surface quality i.e. black patches, small spangles, etc. Kindly let me know what is the effect of Lead, Aluminum in Zn Melt bath and and how we can improve the surface quality of Zn coated sheet.

I need for a catalog about surface defects for cold rolled and Zn coated steel sheet. Please send me if you can otherwise tell me how I can get it?

Thanks,

Waiting for reply,

Truly yours, Mailing Address:

Ayub Naqvi
Pakistan Steel - Karachi, Pakistan