finishing.com -- The Home Page of the Finishing Industry

HomeFAQsSuggested
Books
Help
Wanteds
Advertise
on this site
FORUM
current topics
Live! From beautiful Pine Beach New Jersey: Welcome to the world's most popular metal finishing website

topic 32074

Zinc curtains appear on galvanized steel coils

adv. pointer   western technologies banner  gunatit builders banner

2004

Dear sir,

Kindly we have a strange defect appears on the galvanized steel surface coils this defect look likes a zinc curtains or you can say it look likes the waves and this defect isn't zinc pimples. We'd like to know the universal name, reasons and how to overcome this defect

We appreciate your efforts very much.

Ramy S.Ebrahim
continuous galvanizing steel coils - Sharkia, Egypt


2004

The defect that you seem to be explaining is a wash pattern . Also known as zinc runoff . Usually this occurs when your air knives are to high off of the bath surface . One quick fix for this is to lower the air knives and or increase the strip speed through the line . If this doesn't help try raising the air pressure to the knives and back them off the strip a bit. Usually this defect in appearance happens on heavier gauge , slower running speeds .

Mark Postema
- Rancho Cucamonga , California, USA


2004

Refering to the curtains problem I would like to know if these factors can be a cause of this Defect:

1- The incoming Pickled oiled material ( coil breaks - overpickling- under pickling)

2- The exit strip temperature before dipping in the zinc pot

Hany Mohamed EL-Said Dabies
- Cairo, Egypt



If you have a question in mind which seems off topic, please Search the Site

ADD a Q, A, or Comment on THIS topic START an UNRELATED topicView CURRENT HOT TOPICS

Disclaimer: It's not possible to diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations may be deliberately harmful.

  If you need a product/service, please check these Directories:

JobshopsCapital Equip. & Install'nChemicals & Consumables Consult'g, Train'g, SoftwareEnvironmental ComplianceTesting Svcs. & Devices


©1995-2019 finishing.com, Inc., Pine Beach, NJ   -   About finishing.com   -  Privacy Policy
How Google uses data when you visit this site.