PETpla.net Insider 01+02 / 2020

MAINTENANCE PET planet Insider Vol. 21 No. 01+02/20 www.petpla.net 31 The pellets are propelled at high speeds to blast contaminants from mould surfaces. The combination of kinetic energy and thermal effects breaks the connection between dirt and surface, lifting contaminants away. Other manufacturers found that Cold Jet’s system cut cleaning time 50 to 75%. As dry ice evaporates on contact there is no run-off, rinsing or drying required. Dry ice blasting is also safe and non-toxic, does not create downstream contamination and reduces or eliminates employee expo- sure to dangerous chemical cleaning agents. After a Cold Jet demonstration, Silgan acquired two dry ice blast- ing cleaning systems. One is located on the plant floor; the other is in the maintenance room. Since integrating Cold Jet’s systems into its clean- ing cycles, cleaning time for a single mould was cut from two to three hours to less than 45 minutes. The company has trained all its machine operators in their use and been able to reduce maintenance room staff to a single person. Multiple applications Silgan is now finding ways to use dry ice blasting in other areas of the plant, including a conveyor system for salad dressing bottles. It uses an anti-static spray on the bottles as they move along the conveyor system to prevent them from sticking together. The alcohol-based spray accumu- lates on the conveyor rollers, which slows down production. Cleaning the anti-static spray machine previously involved disassembling the system, cleaning the components by hand with food-grade cleaners and then reas- sembly; the process took at least a day. Operators can now use the Cold Jet system to clean the entire machine in an hour, without taking it apart and risking damage to the components. On occasions when a PET dryer overheats and resin melts inside it, workers would normally have to wait for the dryer to cool down and then remove the resin by chipping it out; a 12-24 hour process. Dry ice blasting clears the resin and enables the dryer to be restored and running in less than two hours. Saving days of downtime “We have also eliminated nearly three days of downtime by using Cold Jet’s system to clean the injection screws on our presses, a process that usually required us to send the screws offsite,” said Pond. “The time savings have been phenomenal as we have been able to clean our equipment better and faster while they are still online. We no longer have to worry about working dangerously close with hot equipment, our on-site environ- ment and safety managers are happy, and we have dramatically reduced the amount of cleansers, degreasers and alcohol that we buy and use for cleaning.” Every 15,000 cycles, machine operators use the Cold Jet system to clean and prepare the moulds for the next round. At the deeper 60,000 cycle cleaning, the maintenance operative removes the majority of the residues by dry ice blasting the moulds, before they are removed from the presses. Line workers clean the rest of the equipment, often using only dry ice blasting. “It is because of Cold Jet’s sys- tems that we are able to meet our high cleaning standards and custom- ers’ mould maintenance cycles,” Pond concluded. Use of Cold Jet’s cleaning systems has enabled Silgan Plastics to reduce scheduled downtime, increase pro- duction time and reduce maintenance costs. www.coldjet.com IMDvista INOX Line Closure Inspection – 100% Inline – Complete solution out of one hand. – Robust, compact and very flexible. – One control center (HMI) for the whole line. IMDvista PECO LUX Preform Monitoring – Shot by Shot – Requires no additional floor space. – No preform orientation necessary and no moving parts. – Up to 80% part inspection. Inspection Systems for the Plastic Packaging Industry IMDvista BOCO SCAN We scan and measure your Bottle Inline – Transparent, opaque, shiny and matte bottles in one system. – Calibrated measurement +/- 5 μm. – Fast automatic product change. Swiss Made | www.imdvista.ch Cleaning injection blow mould