|
>
Department >
Home >
Natural Resources
Natural Resources Extension Program
Calibrating application equipment
Equipment calibration is necessary to ensure manure
and wastewater applications are made at desired rates.
Solid Manure Spreaders:
- Weigh the loaded spreader, then divide this weight
by the spreader volume (spreader length x spreader
width x spreader height). If access to scales is available,
some percentage of the loads can be weighed (for example,
one or two of every 10 loads) and all loads assumed
equal to the average of the weighed loads. However,
scales are usually not available on-site, and another
means of obtaining bulk density is needed.
 An
alternate method of obtaining bulk density involves
weighing a known manure volume then using this information
with volumetric spreader capacity to obtain spreader
capacity in tons. A five-gallon bucket is a convenient
known volume (2/3 ft3) to use for this
measurement.
| 1. |
Measure spreader length ft. x width ft. x height
ft = spreader cubic feet ( ft3). |
| 2. |
A five-gallon bucket equals 2/3 ft3. |
| 3. |
Weigh an empty 5-gallon bucket and write the weight
down. |
| 4. |
Fill the bucket with manure. Do not compact the
manure any more than might occur in the spreader. |
| 5. |
Weigh the full bucket and subtract the empty bucket
weight. The result is the manure weight. |
| 6. |
The manure weight in lbs. ÷ 2/3 ft3
= manure lbs/ft3 |
| 7. |
Take the manure lbs/ft3 x spreader
ft3 = lbs. manure in spreader. |
| 8. |
Take lbs. manure ÷ 2000 lbs/ton = tons
manure in speader. |
| 9. |
Repeat this procedure several times. Sample the
manure at different places. Average the values to
obtain a representative composite of the manure. |
| 10. |
The pounds of nutrients per load of manure are
then found by multiplying the tons of manure per
load by the pounds of nutrients per ton (from a
laboratory analysis). |
Liquid/slurry Manure Spreaders:
- To calibrate liquid/slurry spreaders, first determine
the volume of material in gallons from manufacturer
specifications, or by taking the length x width x
height of the spreader x 7.5 gal/ft3.
- For the volume in cylindrical tanks multiply length
x diameter x diameter x 0.8 x 7.5 gal/ft3.
(0.8 represents 80% of load capacity).
Determining application rate:
|
