Passivation, Dross and Weld Discoloration Removal

Many metals protect themselves from corrosion by forming a passivation layer on their outer surface.  This protective layer is composed of metal oxide or metal nitride and is very thin.  For stainless steels, the layer may be only 1-3 angstroms thick and for metals such as aluminum and titanium, the layer may be up to 50 angstroms thick. (A human hair is 500,000 angstroms thick for comparison).  Passivation can occur naturally with exposure to oxygen or can be assisted by various passivation techniques such as electrolytic anodization, plasma treatment or chemical treatment.  Due to the limited thickness of the passivation layer, the substrate being passivated must be very clean to begin with to prevent discontinuities in the passivation layer which would then compromise the protective nature of the passivation layer.

Machining, cutting, welding, polishing or otherwise “working” a metal substrate generally introduces contaminants which prevent the formation of a uniform passivation layer.  Even particulate in the shop air can contaminate the metal surface and prevent uniform passivation.  Magnus Engineered Equipment can supply the proper equipment to clean and passivate the metal substrates.

Laser or plasma cutting stainless steel or other metals can produce a dross which needs to be removed for part functionality and proper passivation.  The same is true for stainless steel or other metal discoloration that occurs from welding.  Often, aggressive etchants such as hydrofluoric acid and nitric acid are used to remove dross and less aggressive chemistry can be used to remove discoloration.  The use of ultrasonics is useful for removing dross and discoloration and the 20 kHz ultrasonics offered by Magnus Engineered Equipment is the most powerful ultrasonics in the cleaning industry.

Contact Magnus Engineered Equipment to see how we can assist with your metal passivation, dross and discoloration removal needs.

Green Alternative to Hazardous MEK Solvent

A new customer approached Magnus Engineered Equipment looking for help cleaning parts from adhesive and hot glue dispensing label machines.  In their current process, parts are soaked overnight in MEK and then manually brushed clean.

MEK is a highly toxic and unfriendly solvent to humans and the environment, in addition to the costly removal of the hazardous waste by-product.

Two separate removal applications were submitted to Dave Stankiewicz at MEE for cleaning.

 

Adhesive (Henkle) Removal –

Adhesive Removal2 Adhesive Removal

Hot Glue (DURA PRO – M-749) Removal –

Hot Glue Removal Hot Glue removal2

Once MEE received the customers parts, Dave partnered with our in-house chemical engineer to determine a less toxic solution.  Upon their investigation they developed and refined an eco-friendly, bio-degradable cleaning solvent for both cleaning applications.

 

Test Results –

We were successful in removing the adhesive (Henkle Aquence PS 2417/GELVA GME2417) and Hot Glue (DURA PRO-M-749) from the adhesive & hot glue dispensing label machines. We used a 50/50 blend of the eco-friendly cleaning solution in a heated, wash/agitation tank and a heated, clean water, rinse/agitation tank.

 

Final Product –

FINAL

Acetone Replacement

A company which manufactures composite pressure vessels was manually cleaning resin contaminated stainless steel components with Acetone and manual scraping.  The company wanted to find a better way of doing this and approached Magnus Engineered Equipment.  In order to be successful, fully cured and partially cured resin materials needed to be removed from a variety of stainless steel substrates.  Magnus Engineered Equipment provided a process which uses novel bio-degradeable chemistry to economically remove cured and uncured resin in very fast times (less than 30 minutes).  The novel chemistry lasts longer and costs less overall than the acetone it replaces, and no manual labor is required.  Furthermore, operator exposure to acetone and acetone disposal issues were eliminated.  This “green” process can also be used to replace other common cleaning agents such as Methyl Ethyl Ketone (MEK), toluene and other thinners as well as remove other organics such as polyester, vinyl ester or epoxy resin, gel coats, adhesives, urethanes, waxes, paints and stains.