Full electric processing with KeestrackPublished 2/3 at 15:56
Five end products with a production capacity of 180t/h and diesel consumption of 60litres/h were the results of a crushing and screening combination of four mobile Keestrack plants tested last autumn.
The tests were conducted during customer demonstrations with Keestrack’s Norwegian dealer Fredheim Maskin that included the presentation of hybrid drive technology and new jaw crusher B4e and the mobile cone H4e, both with new drive systems,
Highlight was the B4e jaw crusher with stacker S5e, the H4e cone with 3-deck-afterscreen module and the final 2-deck-classifier K3e for five end product fractions. With a feed size of 600mm and different sets of end products, including double crushed chippings the combination reached a maximum production of 180t/h. Without activating their on-board diesel engines all machines were powered through a single 500kVA external generator set. Consumption analyses over several days gave average values of under 60litres/h.
“We were surprised by these results,” said Keestrack president Kees Hoogendoorn. “Even if these values are quite specific, they clearly reflect the high economic potential of our full-hybrid technology. Applied in a mobile multi-stage processing line, it offers great advantages for contractors. Not only in daily practice, but specifically in long-term evaluation if we consider lower maintenance costs and longer service life.”
“Every new level in development brought important savings in diesel consumption. With their substantially smaller hydraulic circuits our hybrid systems provide advantages in maintenance, availability and safety, especially when working in environmentally sensitive areas.”
While the screeners and conveyors on hybrid Keestrack classifiers and stackers are operated electrically, the diesel driven hydraulics only supply hydraulic cylinders and crawlers. All Keestrack crushing units were previously only powered directly through the on-board diesel engine. “Electric drives supplied via external generator sets or mains certainly offer high saving potentials, but without compromising the plants’ mobility, crushing performance and productivity, which depends on optional modules with high power demands,” said Hoogendoorn.
The new Keestrack B4/B4e jaw crusher is optionally available with conventional diesel-hydraulic drive or as a full-hybrid e-version. With active two-deck pre-screening and the re-designed 1100mm x 700 mm jaw crusher it features the patented N.S.S. overload protection. The full-hybrid Keestrack B4e is equipped with a 242 W diesel engine and a 225kVA on-board generator. The generator supplies the 110kW crusher motor, all other electric drives on conveyors and screens and the separate 55kW electric motor/hydro pump unit for the installed hydro drives. During plug-in operation the diesel engine does not have to be started, the whole energy management is controlled automatically including the electric supply of a secondary unit.