When the weighbridge and the pit count disagree
Pit counts assume a body factor and a swell. The weighbridge records wet tonnes after rain, or dry tonnes after a long haul on a hot road. Those are different numbers. Before anyone talks about “missing stone,” we write down which moisture and which body factor each side used.
On one basalt site south of Ho Chi Minh City, the plant was consistently five percent below the pit. The trucks were heaping. The pit counted heaps as struck. Once both sides used the same rule, the charts sat together. The argument had lasted two months; the walk along the dump took an afternoon.
We still chart both series. Hiding the weighbridge to make the pit look tidy helps nobody at the month-end meeting. The useful page is the one that shows both lines and a short note on moisture and body factor for that week.