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2.4 Harvester Performance Monitoring
To ensure harvesting machines are suited to their operating conditions and crop characteristics they
are working in, and are achieving optimum productivity their performance must be evaluated.
Performance is a measure of some output or behaviour and is the first step to improving productivity.
The information that is collected can help match appropriate machinery to site conditions and
determine if machines are performing optimally.
2.4.1 Loss Processes
Sugar System
The process of harvesting sugarcane to produce a product low in or free of extraneous matter (EM)
has always been accompanied by the loss of millable cane. This loss increased considerably with the
change from whole-stalk to ‘chopped cane’ harvesting and has been exacerbated with the move into
green-cane harvesting with the increased demand for removal of EM (Brotherton 2002).
There has always been an industry awareness of the cane loss problem, but the magnitude of losses
has been hidden to a large extent by the invisible nature of the loss. That is, desiccated billets through
the extractor fan are difficult to identify and cane and sugar loss is difficult to measure. Industry has
demanded increased machine throughput, and this has, to some extent, overridden the effectiveness of
measures to minimise cane loss in harvesting.
Harvesting losses occur throughout the harvesting process, from feeding and gathering through to
chopping, cleaning and transferring to infield haulouts.
Whilst losses have generally been presented as cane loss, the loss of Pol (a sucrose approximation)
and loss of CCS (recoverable commercial sugar) have become more relevant indicators in recent
years as these are the intended products of the current industry. These parameters also respond to
stalk degradation and deterioration that are omitted in cane loss.
Brotherton (2002) considered that an accurate, absolute magnitude of loss is necessary for economic
evaluation of harvesting losses. The Australian sugar industry has invested significant resources in
the assessment and measurement of losses during cane harvesting.
Table 2.7 shows the typical losses from various components of the harvester during harvesting.
Table 2.7 Typical cane losses during harvesting (SRDC, 2004)
Process Losses Losses
Range, % Average, %
Gathering 1-2 1.0
Basecutter 1-3 2.0
Feedtrain/Chopper 2-6 4.5
Extractor 3.5-15 9.0
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