The graphs provide data on two driving patterns i.e. race track (around the paddock) and back and forth. When the race track pattern is employed, opposite sides of the spreader discharge are overlapped, e.g. the right discharge gets placed on top of the left discharge. For back and forth driving pattern, the spreader discharge from the same side is overlapped, e.g. right discharge gets placed on top of the right discharge.
The first graph plots the CoV against the bout width for the product spread. The allowable spread width is represented where the red and black lines are under the target 15% CoV industry benchmark. Any part of the graph over the 15% CoV is outside the Accu-Spread standard. The second graph, the distribution graph, shows the evenness of spread in a single pass behind the machine. The zero on the X axis represents the spreader line of travel and the dot points on the graph reflect the collection trays either side of centre.
The Accu-Spread graph in figure 1 indicates the recommended maximum spread width for both racetrack and back and forth is 34 m in this example. The spreader can spread at any width between 5m and 19m and between 31m and 34m. Spreading at 25 m would result in an unacceptable spread pattern for this machine.
There is no minimum bout width standard for a machine to be tested and certified. The test performance of the machine is recorded and, subsequently, a certificate is issued showing that level of performance.
The objective for a spreader operator is to have detailed knowledge about the performance of a machine; to be able to make the necessary adjustments to achieve optimal performance; to have the machine re-tested and certified as operating at this optimal level; to utilise this to improve productivity and achieve a marketing edge through quality assurance.
Figure 1 Accu-Spread graph