Technical
WORKING WITH
STAINLESS STEEL
By PFERD South Africa
Stainless steel ( INOX ) is often a first-choice material to work with because of its corrosion resistance , longevity , and cost-effectiveness . Working with INOX , however , does pose some challenges – especially if incorrect tools and processes are used .
Marius Steyn , training manager at PFERD South Africa explains , “ The South African stainless steel and steel industries are well established in the supply of high-quality steel . Stainless steel applications can be found in all of the major industrial sectors , be it food , beverage , pharmaceutical or automotive and it is important to achieve the specified surface conditions and finishing . In order to obtain a high standard , certain tools and in-situ arrangements need to be adhered to for the process to be successful and cost-efficient .”
ESTABLISH THE FUNCTION Differing surface functions determine the final surface roughness and finish of the stainless steel . Industrial applications , for example , may require a surface definition that prevents bacterial growth to ensure a safe and hygienic environment as well as to maintain corrosion and wear resistance in order to prevent structural damage .
In the retail or architectural sector , aesthetics take precedence and priority is placed on the stainless steel ’ s final appearance . Therefore , it is important to establish what function the finished stainless-steel surface will perform .
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All images supplied .
A brushing technique to clean a circular welded section .
Stainless steel is a very versatile material that can be used in a variety of applications .
RACA Journal I March 2022
ELIMINATE CROSS CONTAMINATION Stainless steel is an alloy of iron with a minimum of 10.5 percent chromium . Chromium produces a thin layer of oxide on the surface of the steel — the “ passive ” layer — this prevents surface corrosion .
Damage to the passive chromium layer , caused by incorrect working methods can lead to the stainless-steel rusting . Crosscontamination of INOX is one form of damage that can cause it to rust .
“ The prevention of cross contamination of non-stainless with stainless steel is a crucial factor when working with stainless steel in workshops . We advise customers to protect the work components at hand from surface contamination and contamination from other materials ,” Steyn said . Sparks from close by metal cutting and grinding operations can embed themselves in the stainless steel and lead to its eventual deterioration . This can occur sometime after installation of the stainless-steel products and would then require costly repairs in accordance to best practises .
Only specialised grinding and polishing components for stainless steel should be used and all non-stainless consumables
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