German researchers have compared hydraulic machines with electric models moulding the same part

German researchers have compared hydraulic machines with electric models moulding the same part

Electric injection moulding machines use up to 71% less energy than hydraulic machines, a comprehensive study by a German university has revealed. Thomas Kamps of the University of Duisburg-Essen presented the findings at the Society of Plastics Engineers’ Antec conference in Chicago yesterday.

The researchers worked with five injection moulding facilities, each operating hydraulic and electric machines from the same manufacturer.

The participants in the project were: Fischerwerke running Arburg machines; Braun with Ferromatiks; Lechner equipped with Battenfelds; Schiebl, which has Engels; and FTE Automotive Systems operating Demags. In the latter case, the hydraulic machine was compared with a hybrid Elexis model, rather than the all-electric designs used in the other four comparisons.

In each plant the same part was produced on pairs of hydraulic and electric/hybrid machines of a similar size and age. Looking at the energy consumption of the drives alone, the savings of the all-electric and hybrid machines ranged from 19% to 71% compared to the hydraulic units, with an average reduction of around 50%.

Considering the total power consumption for the moulding machine system, including the machine controller, barrel heaters and temperature control unit, the energy savings of the all-electric and hybrid machines were between 12% and 51% with an average of 30%.