Calculating Grain Weight Shrinkage
Calculating Grain (corn) Weight Shrinkage Due to Mechanical Drying
One of the factors involved in mechanically drying grain is the “expense” of the weight lost during the drying process. Grain buyers use a number of procedures to determine how much “dry” corn they will pay for when “wet”corn is delivered for sale.
The majority of weight loss from mechanical drying comes from water that is removed from the grain .The number of ”dry” bushels remaining from a given number of “wet” bushels dried to a given final moisture content can be determined by the equation provided to the below:
“Wet” bu. = lbs. of “wet” corn divided by 56
SF = Shrink factor from the following table based on final desired grain moisture content
PR = Points of moisture removed (original moisture minus final moisture content)
|Example: 56,000 lbs. of grain at 26% moisture to be dried to 15% moisture.|
|"Dry" bu =||1,000 “Wet” bu. – (1,000 x 0.01176 x 11)|
|1,000 – 129.36|
Water Shrink Factors for Drying Shelled Corn to Various Moisture Levels
|Final Moisture (%)||Water Shrink Factor (shrink/point)|
*Source:Adapted from Purdue Extension publication NCH-61, Calculation Grain Weight Shrinkage in Corn Due to Mechanical Drying.