Generally, greater care is required in storing and handling stainless steel than carbon steel to avoid damaging the surface finish (especially for bright annealed or polished finishes) and to avoid contamination by carbon steel and iron.
Storage and handling procedures should be agreed between the relevant parties to the contract in advance of any fabrication and in sufficient detail to accommodate any special requirements. The procedures should cover, for instance, the following items:
- The steel should be inspected immediately after delivery for any surface damage.
- The steel may have a protective plastic or other coating. This should be left on as long as possible, removing it just before final fabrication. The protective covering should be called for in the procurement document if it is required (e.g. for bright annealed finishes).
- Storage in salt-laden humid atmospheres should be avoided. Storage racks should not have carbon steel rubbing surfaces and should, therefore, be protected by wooden, rubber or plastic battens or sheaths. Sheets and plates should preferably be stacked vertically; horizontally stacked sheets may get walked on with a risk of iron contamination and surface damage.
- Carbon steel lifting tackle, e.g. chains, hooks, and cleats should be avoided. Again, the use of isolating materials, or the use of suction cups, will prevent iron pick-up. The forks of fork lift trucks should also be protected.
- Contact with chemicals including undue amounts of oils and greases (which may stain some finishes) should be avoided.
- Ideally, segregated fabrication areas for carbon steel and stainless steel should be used. Only tools dedicated to stainless steel should be employed (this particularly applies to grinding wheels and wire brushes). Note that wire brushes and wire wool should be of stainless steel and generally in a grade that is equivalent in terms of corrosion resistance (e.g. do not use ferritic stainless steel brushes on austenitic stainless steel).
- As a precaution during fabrication and erection, it is advisable to ensure that any sharp burrs formed during shearing operations are removed.
- Consideration should be given to any requirements needed in protecting the finished fabrication during transportation.
Thats all for today..see u next articles.
