Cummins sees efficiency gains with Tier 4
By Steve Skinner29 June 2009
A head-to-head test conducted by Cummins has shown its Tier 4 Interim (Stage IIIB) QSB6.7 engine offers a +5% fuel efficiency improvement over its Tier 3 (Stage IIIA) predecessor.
The fuel consumption test was carried out under site conditions across a series of duty cycles. Identical wheeled loaders in the 142 to 149 kW class were used to test the two engine types with both having the same power output, peak torque and rated speed.
The improved fuel efficiency of the QSB6.7 engine was achieved without compromising machine performance. Indeed, faster engine response to load demands meant the Tier 4 Interim (Stage IIIB) powered machine completed the fuel duel tests within shorter cycle times.
"The results of the fuel duel test speak for themselves," said Hugh Foden, director of off-highway business at Cummins. "OEMs can expect lower operational costs and enhanced productivity from Cummins-powered Tier 4 Interim (Stage IIIB) compliant engines.
"Because we design and manufacture the complete engine system from air-in to exhaust-out after-treatment we've been able to produce a cleaner and more fuel-efficient combustion process," said Mr Foden.
In the back-to-back evaluation the same driver operated both wheeled loaders and each machine was fitted with the same bucket size and ran on equal tyre pressures to eliminate any variables that could influence the results. Fuel consumption was measured using a secondary fuel tank, which was weighed after each test to record the exact amount of fuel used.
The +5% fuel savings represented an average measured over different duty cycle tests, with each test performed repeatedly to fully validate the results.