Rexam Pharma GmbH is focusing future equipment investments on all-electrics, after a study of electric vs. hydraulic molding machines at its Neuenburg, Germany, plant revealed huge energy-savings potential, said product and technology manager Frank Henninger.
Rexam Pharma has completed a comparative analysis of KraussMaffei AG's EX series all-electric machines against its hydraulic CX units, Henninger said during a KraussMaffei open house in Munich earlier this year.
The results, he said, in terms of energy usage and repeatability, have led to a change in strategy at the firm: Rexam Pharma will always go for all-electric machines in future.
As part of the study, Rexam molded a 1.8-ounce polypropylene part in a 16-cavity tool on 160/750 CX and EX models. The EX resulted in an energy cost of about 0.75 kilowatt-hour per kilogram compared with 1.43 kwh/kg for the CX, the company said.
Tests comparing KM's 80/180 CX and EX machines showed better repeatability on a nominal 13.2-millimeter dimension or about one-half inch with the EX achieving standard deviations of 0.006mm compared with 0.009mm for the CX.
The closing and opening times were faster with the EX machines, too. Rexam cited 0.67 second and 1.04 seconds for the EX machines, compared with 0.86 and 1.18 seconds for the CX models.
All of the injection molding machines at the Rexam Pharma plant in Neuenburg operate in a clean room, where the EX water cooling system reportedly keeps the temperature down, relieving pressure on the air conditioning.
Rexam Pharma is a unit of London-based packaging company Rexam plc.
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