Accurately estimating the storage capacity of a grain bin is crucial for farmers and agricultural businesses. It impacts decisions related to harvesting, storage logistics, and inventory management. This calculator helps you determine the volumetric and weight capacity of your grain bin.
How the Calculation Works
The calculation involves two main steps: determining the volume of the cylindrical bin and then converting that volume into a weight based on the grain's density.
1. Calculating the Volume:
The volume of a cylinder is calculated using the formula:
Volume (cubic feet) = π * (radius)² * height
Where:
π (Pi) is approximately 3.14159
radius is half of the bin's diameter (Diameter / 2)
height is the wall height of the grain bin.
The result is the internal storage volume in cubic feet.
2. Calculating the Weight Capacity:
Once the volume is known, we can estimate the weight of the grain it can hold. This depends on the bulk density of the specific grain, which is the weight of the grain per unit of volume. Different grains have different densities due to their size, shape, and how tightly they pack.
Common grain densities (approximate, and can vary):
Corn: 45.0 lbs/cu ft
Wheat: 48.0 lbs/cu ft
Soybeans: 47.0 lbs/cu ft
Barley: 38.0 lbs/cu ft
Oats: 26.0 lbs/cu ft
Canola: 41.0 lbs/cu ft
For grains not listed or for more precise calculations, you can input a custom density. The default for "Other" is set to 45 lbs/cu ft.
Why This Calculator is Useful
Harvest Planning: Estimate how much grain your existing bins can hold before harvest.
Storage Management: Determine if you have sufficient storage space for your yield.
Inventory Tracking: Provide a reasonable estimate of the amount of grain stored.
Equipment Sizing: Help in choosing augers or conveyors suitable for the volume and weight of grain.
Disclaimer: This calculator provides an estimation. Actual capacity can be affected by factors like grain moisture content, bin aeration systems, and how the grain is loaded (e.g., flat bottom vs. conical bottom bins). Always consult manufacturer specifications for precise bin ratings.
function calculateCapacity() {
var diameter = parseFloat(document.getElementById("binDiameter").value);
var height = parseFloat(document.getElementById("binHeight").value);
var grainType = document.getElementById("grainType").value;
var customDensityInput = document.getElementById("customDensity");
var customDensity = parseFloat(customDensityInput.value);
var grainDensities = {
"corn": 45.0,
"wheat": 48.0,
"soybeans": 47.0,
"barley": 38.0,
"oats": 26.0,
"canola": 41.0,
"other": 45.0 // Default for 'Other'
};
var density = grainDensities[grainType];
if (grainType === "other") {
if (isNaN(customDensity) || customDensity <= 0) {
alert("Please enter a valid Custom Grain Density when 'Other' is selected.");
return;
}
density = customDensity;
}
if (isNaN(diameter) || diameter <= 0) {
alert("Please enter a valid Bin Diameter.");
return;
}
if (isNaN(height) || height <= 0) {
alert("Please enter a valid Bin Wall Height.");
return;
}
var radius = diameter / 2;
var volume_cu_ft = Math.PI * Math.pow(radius, 2) * height;
var weight_lbs = volume_cu_ft * density;
var resultValueElement = document.getElementById("result-value");
var resultUnitsElement = document.getElementById("result-units");
// Format results to two decimal places for readability
resultValueElement.innerText = weight_lbs.toFixed(2);
resultUnitsElement.innerText = "Pounds (lbs)";
}
document.getElementById("grainType").addEventListener("change", function() {
var customDensityGroup = document.getElementById("customDensityGroup");
if (this.value === "other") {
customDensityGroup.style.display = "flex";
} else {
customDensityGroup.style.display = "none";
document.getElementById("customDensity").value = ""; // Clear custom density if not selected
}
});