The massive quantities and diverse grades of stainless steel used in the mining, petroleum/oil and gas industries are sometimes in the most corrosive environments. Electropolishing is seriously considered as beneficial within these industries, optimizing stainless steel component lifetime ensuring less downtime and maintenance. This is of economic and environmental benefit.
Unprocessed stainless steel surfaces contain free iron, iron-oxides and other surface contaminants. These can be worsened by machining or fabricating. The contaminants become trapped underneath a "smeared skin" created by mechanical operations. Metaglo WA can resolve this problem entirely.
Surface contaminants and the smeared skin are removed electrochemically and the remaining surface is positively the cleanest, most passive surface possible due to the formation of the thickest chrome-oxide layer achievable by any process.
The rate of metal removal is controllable and any required dimensions with close tolerances do not pose a problem, as a micro finish can be achieved to required specifications. Stainless steel, when immersed in nitric acid (pickling), is dangerous and detrimental to the surface as it attacks the iron, leaving pits where the iron once existed. This can lead to IGA or Intergranular Attack, where the remaining metal surface will corrode inwardly and outwardly. The results are metal fatigue and surface corrosion, disastrous to any sterile application.
Thorough surface passivation, produced by Metaglo WA electropolishing, is necessary to achieve a pure clean stainless steel environment, essential for gas or liquid valves and pumps, bearings, vacuum systems and fuel supplies.
Scale or discolouration is caused by heat treating, annealing, carburising, welding or soldering. This carbonaceous smut and the iron porosity in the metal are completely eradicated from the surface after Metaglo WA electropolishing.
Metaglo WA also removes the skin remaining on metals after casting or forging. The surface quality and appearance is improved allowing subsequent machining operations to be performed with less time, effort and tool wear.
Hardened surfaces and metal fatigue caused by stresses travelling inwards can shorten service life. Metaglo WA removes these electrolytically which is the only process providing a successful result in descaling.
The ability of Metaglo WA processing to reduce the micro finish of stainless steel and nickel alloys, is of primary importance in numerous applications.
A profilometer is used to measure the roughness of a surface and gives a reading expressed in RMS (Root Means Squared) or RA (Roughness Average). Metaglo WA processing can reduce the surface RA while leaving the dimensions of the part within tolerances.
This is achieved by electrochemically eroding the roughness. The high spots or "peaks" are attacked more rapidly than the low spots or "valleys". This is crucial when given dimensions must be maintained while refining the surface roughness. Deburring of the metal is accomplished, thus requiring no further treatment. The smooth surface reduces particulate entrapment, therefore impurities are restricted from clinging to the processed surface. Manufacturers of surgical tools and implements often take advantage of the benefits of this process. This process replaces costly hand and mechanical polishing and in the worst case, replacing the item.
The presence of Hydrogen in stainless steel is accountable for three major problems:
- Bacterial Growth
- Metal Fatigue
- Explosive Conditions
Electropolishing is the most effective method for removing hydrogen from stainless steel. Detailed testing has proven that only this process has such thorough results. The hydrogen is not only removed at the surface, but throughout the metal as well. This is of paramount significance.
Electropolishing is the most effective method for reducing hydrogen embrittlement from stainless steel surfaces. Detailed testing has proven that only this process has such thorough results. The hydrogen is not only reduced at the surface, but throughout the metal as well. This is of paramount significance.
Traditionally, bacterial contamination has plagued surgical, medical, pharmaceutical and food surfaces. However, anaerobic bacteria (e.g. Staphylococcus) is unable to grow in an environment absent of hydrogen. The applications are virtually limitless as Metaglo WA processing severely restricts bacterial growth by removing hydrogen. Costly cleaning and downtime are greatly reduced due to the highly passive, smooth and corrosion resistant stainless steel surfaces.
Metaglo WA has the folowing bath size:
- Tank 6m long x 0.90m wide x 1.2m high. Therefore double dips up to 2.4m high can be achieved.
Electropolishing is seriously considered as beneficial within the mining, petroleum/oil and gas industries as optimizing stainless steel component lifetime, ensuring less downtime and maintenance. This is an economical and environmental benefit.
Why Metaglo WA is environmentally friendly.
The solutions used in electropolishing are called electrolyte. These electrolytes can be Finite or Infinite. Finite electrolytes require acid renewal as the solution degrades and fowls over time. They leave a larger environmental footprint as they require constant waste removal which in economically and environmentally costly.
Metaglo WA uses an Infinte electrolyte which can be filtered and purified of contaminants, then re-used through the system, leaving zero cost and ‘No’ environmental footprint.
Metaglo WA electropolishing allows maximum life out of your stainless steel item and therefore minimizing replacement environmental footprint. Electropolishing also results in minimal maintenance.
Think about how much effort and cost is required to replace, machine and fabricate stainless steel, and then permanently using maintenance products. This all requiresexcessive chemicals and toxic waste and a 10 times larger environmental footprint.
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Metaglo WA procedures use fully recycled systems. Our infinite electrolyte is captured and closely monitored.
- The solutions used in electropolishing are called electrolytes. These electrolytes can be "Finite" or "Infinite."
- Finite electrolytes require acid renewal as the solution degrades and fowls over time. They leave a larger environmental carbon footprint as they require constant acid renewal and waste removal which is economically and environmentally costly.
- Metaglo WA uses an Infinite electrolyte which can be filtered and purified of contaminants then re-used through the system minimizing economic and environmental impact. Metaglo WA electropolishing maximizes the lifetime and minimizes the maintenance of your stainless steel!
Stainless steel requires a regular maintenance program to protect the chromium-oxide layer. Washing removes contaminants, such as salt, dirt and dust that can cause corrosion and is necessary to avoid tea staining.
Rain washing the surface is helpful in reducing tea staining, so design the job to take advantage of the rain, but ensure good drainage. The stainless steel should also be washed when cleaning the surrounding area.
For best results wash with soap or mild detergent and warm water, followed by rinsing with clean cold water. The appearance of the surface can be further improved if the washed surface is wiped dry. We recommend "Wicked" metal polish for maintaining polished surfaces. The product is non abrasive and can remove fingerprints, mild scratches, minor stains, and dirt and markings resulting from the chlorine in water.