Cleaning injection molds can cause a lot of unnecessary downtime in automotive production. Dry ice blasting is the rare alternative that can both reduce downtime and provide a thorough cleaning.
The A. Raymond Group is one of the leading development and production partners in the automotive industry. In addition to vehicles, the company supplies a quick fastening and connecting system for the solar, household article, aerospace, electronic and construction industries. Production takes place at 20 locations around the globe, including the subsidiary A. Raymond GmbH & Co. KG, founded in Lorrach, Germany.
At the Lorrach facility, special fasteners and couplings for products are founded for injection molding. These include plug systems, screw parts and windscreen washer nozzles that are made out of polycarbonate, polyamide and POM, which are produced in three layer runners.
Cleaning the tools posed a number of problems for the Lorrach facility:
- Parts needed to be removed from the machine and disassembled so the small cavities could be cleaned with special tools, brushes and solvents.
- The spool was cleaned in an ultrasonic bath.
- The time required to disassemble, clean and reassemble the tools took several hours, causing significant downtime on the machine.
- The abrasive tools and chemicals often damaged the machine parts.
“Plastic contains flame retardants and additives that leave a coating in the cavities of the tools. This coating needs to be removed every two to three days to ensure that the quality of the parts will not be affected. The connector systems also need to go through multiple validation tests.”
- Stefan Preller, Director of Manufacturing Industrialization (DMI)
Blasting with Dry Ice MicroParticles
In order to optimize their cleaning process, Preller researched dry ice cleaning as a possible solution and contacted several dry ice blasting manufacturers for a solution.
The dry ice blasting process uses non-abrasive media in the form of recycled CO2 particles that won’t damage surfaces or equipment. The combination of dry ice cleaning’s kinetic energy and thermal effects break the connection between the dirt and surface, lifting away contaminants.
Unlike blasting with other media, dry ice cleaning:
- Does not leave any secondary waste
- Is safe and non-toxic
- Does not create downstream contamination
Utilizing the traditional 3mm dry ice pellets to clean was unsuitable for A Raymond because the dry ice particles could not access the small cavities and contours of their tooling and molds.
In Preller's research he discovered Cold Jet's MicroParticle blasting technology. In this process, a block of dry ice is placed into the Cold Jet i3 MicroClean and the dry ice is shaved into MicroParticles from the block. The resulting MicroParticles are much finer and less aggressive than traditional pellets. They are also able to access hard to reach areas. MicroParticle machines require less compressed air to accelerate the smaller particles through the blast hose, so the machines are often quieter than pellet blasting machines.
Dry Ice Blasting Delivered Results
1) Increased process uptime by 25%
With a process that makes it virtually impossible to damage tools during cleaning, dry ice blasting has positively impacted process uptime by 25%. Machines are up and running more efficiently than when other cleaning methods were used.
2) Reduced downtime for cleaning from two to three hours to only 45 minutes
Mobile and compact, the dry ice blasting system is driven to the relevant injection mold, connected to a compressed air supply and static ground cable, and the molds are cleaned with the appropriate nozzle. This process takes no more than 45 minutes.
3) Consistently passes validation tests
Effective cleaning ensures that the vent of the injection mold is always optimal; therefore, validation tests of connector systems no longer fail.
4) User-friendly operation
The machine is also simple to operate:
“I taught the staff how to operate the dry ice blasting system in less than 20 minutes. Previously, a specially trained staff was required for tool cleaning and now it can be done easily by anyone. This is a significant advantage on the weekend, especially during the continuous shift system.”
- Stefan Preller
5) Environmentally friendly and worker safe
On top of these other improvements, dry ice blasting uses media that is environmentally friendly and eliminates the need for employees to come into contact with harmful chemicals, resulting in a much safer work environment.
At A. Raymond in Lorrach, three dry ice blasting systems are in use. Two of them are used for tool cleaning every two days. The third system is used in the Technical Plastic Maintenance department to clean injection molds.
“Due to the time savings, we were able to increase machine utilization significantly and the machine paid for itself in less than one year. Because of the savings in both time and costs, I am sure these systems will be used at other plants. They allow for a significant increase in process reliability and have helped us to maintain our high quality standards."
- Stefan Preller