Category Archives: Magnus Chemistry

Magnetostrictive Ultrasonic Cleaning Succeeds Where Less Powerful Piezoelectric Ultrasonics Fail

Case Study: nPB (N-Propyl Bromide) Replacement

N-Propyl Bromide (nPB or 1-Bromopropane) is a toxic solvent often used in cleaning or vapor degreasing applications. As a suspected human carcinogen and proven animal carcinogen, it has been targeted by the U.S. Environmental Protection Agency for risk evaluation and the European Union has banned it’s use without authorization after July 4, 2020. It is clear that nPB use will soon be banned or greatly restricted and existing users are encouraged to look for a replacement.

Companies presently using nPB are searching for safe, economical and effective replacements for nPB and Magnus Engineered Equipment has been successful in assisting customers to replace nPB with less costly, non-hazardous chemistry while accomplishing the same or improved cleaning. The following is an example where Magnus Engineered Equipment helped a customer develop a cleaning process utilizing nPB and then further helped them replace nPB with non-hazardous, environmentally friendly chemistry.

Highly crosslinked polyurethane is one of the toughest and most durable polymers, and producers often mold this material into usable items such as wheels for roller coasters and skateboards, hoses and automotive suspension bushings. The molds can become contaminated and cleaning the molds is a difficult and time-consuming process.

MEE worked with a customer to develop a chemical cleaning process for their polyurethane molds (steel and aluminum). Previously, a media blasting method was utilized to clean the molds and the process required mold dis-assembly and up to 4 hours of blasting. Using MEE Powersonics, the world’s most powerful magnetostrictive ultrasonic cleaning technology, MEE was able to demonstrate mold cleaning in less than 5 minutes with no mold dis-assembly. (This result was not achievable with less powerful piezoelectric ultrasonic cleaning). With this success in hand, attention was directed at finding a safer chemistry. Powersonics coupled with Acrastrip chemistry by US Polychem was able to replicate the performance achieved with nPB. Acrastrip is a water-soluble, non-hazardous environmentally friendly cleaner that was designed to replace acetone, toluene, MEK, Methylene Chloride, Xylene, MIBK, NPB, Ketones, and other petroleum-based products. In addition, Acrastrip is HAPS free, biodegradable, non-flammable, non-toxic, pH neutral and recyclable.

A Polyurethane mold cleaned with powerful 20 kHz magnetostrictive ultrasonic technology and water-based Acrastrip cleaner

The cleaning tandem of MEE magnetostrictive ultrasonics and Polychem Acrastrip is one example of how MEE can assist customers who are looking to replace nPB with a safer, more cost-effective and quality cleaning operation. MEE Powersonics is the world’s most powerful ultrasonic cleaning technology and can often deliver successful cleaning where less powerful piezoelectric ultrasonics fail.

 

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 Magnus Engineered Equipment 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, our Sales Agent 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