# Dry Bulk Storage Dome Sizer

## Product Reference

*Click product density to auto-populate the storage sizer.*

Product | angle | lbs/ft³ | kg/m³ |
---|---|---|---|

Ammonium Nitrate | 32° | 50 | 800 |

Ammonium Sulfate | 38° | 65 | 1040 |

Cement, Clinker | 35° | 85 | 1360 |

Cement, Portland | 12° | 90 | 1440 |

Coal, Bituminous | 35° | 50 | 800 |

Coal, Lignite | 38° | 40 | 640 |

Corn | 21° | 45 | 720 |

Distillers Grain | 32° | 30 | 480 |

Fly Ash | 20° | 60 | 960 |

Gypsum | 35° | 75 | 1200 |

Iron Ore | 30° | 120 | 1920 |

Limestone | 38° | 90 | 1442 |

Peanuts | 35° | 20 | 320 |

Phosphate | 30° | 60 | 960 |

Potash | 25° | 70 | 1120 |

Salt | 25° | 75 | 1200 |

Sand | 25° | 100 | 1600 |

Soda Ash | 32° | 60 | 960 |

Soybeans | 24° | 50 | 800 |

Sugar | 35° | 55 | 880 |

Sulfur | 30° | 55 | 880 |

Urea | 32° | 48 | 770 |

Wheat | 28° | 48 | 770 |

## Using the Dry Bulk Storage Dome Sizer

The MDI Dry Bulk Storage Dome Sizer reverses the inputs from the MDI Dry Bulk Storage Dome Calculator. Instead of calculating product capacity inside a given dome, the sizer calculates the size of a dome necessary to store a given product capacity. Like the calculator the stored material is poured into the top of the dome, filling the structure, and forming a pile with a cone shape at the top. The sizer will calculate a selected range of dome designs from a low-profile pile-cover to tall silo-like dome structures.

Product name, density, angle of repose, and desired capacity are determined by the user. The Product Reference table contains a list of commonly stored products with recommended angles of repose and density values—imperial or metric. These are linked to templates to help start the design process.

Click “Switch to Calculator” to copy product details and calculated dome dimensions to the Dry Bulk Storage Dome Calculator.

Parameters are stored in the page URL and can be bookmarked, saved, or shared. Use “Copy Link” to share the URL or click “Copy Results” for an email-friendly copy of all results. Print or save the page as a PDF for a professional copy of the drawing and results.

Be aware that just because the calculator can draw a structure, it does NOT mean the structure can be built. This calculator is just a tool. Always consult with qualified professionals before proceeding with a project.

*This calculator is subject to our Terms of Service.*

## Product Inputs

**Product Name.** The name of the product to be stored.

**Angle.** The average angle of repose in degrees for the product. As the product is poured into the structure it forms a pile cone with a slope roughly equal to the angle of repose.

**Density.** The numerical value of the average product density. Use the Product Reference table for good starting values.

**Measure.** The product density units in either pounds per cubic foot or kilograms per cubic meter.

## Capacity and Dome Inputs

**Capacity.** The total amount of product to store in the dome.

**Weight.** The unit of measure for the total stored capacity. Valid units are US bushels (bu), pounds (lbs), US tons (ton), kilograms (kg), and metric tonnes (tonne).

**Style.** A selection of five design shapes for the target dome.

**pile.**The pile cover design will find a dome that perfectly covers the pile cone poured onto the floor. The product does not rest against the dome so the dome requires less reinforcement, however, the diameter is larger so more land is required.**hemi.**The hemisphere dome is a common shape used for smaller dome storages.**short.**The short design is a hemisphere atop a stem wall with a fixed height of 16 feet (5 m) to accommodate an industrial door for front-end loaders.**medium.**The medium design is a hemisphere with a stem wall half as tall as the height of the dome. Sometimes this design may result in a stem wall shorter than 16 feet (5 m) and the*short*design maybe more appropriate.**tall.**The tall design is a hemisphere with a stem wall equal to the height of the dome. This is an optimal shape to reduce the dome diameter and land requirements but does need more concrete and steel reinforcement.

**Overlay.** A scaled, graphical overlay to assist in visually representing the building size and purpose. The default overlay is the small front-end loader. Use “heavy” for a large capacity front-end loader.

**Units.** The selected unit will label the calculator outputs and properly scale the overlay. Note that all dome dimensions are output in the selected unit along with the calculated output capacities.

**ft**All measurements are in feet with the product capacity calculated in US tons.**m**All measurements are in meters with the product capacity calculated in metric tonnes.

**Note: Density measures and product capacities are cross-compatible where density can be in pounds per cubic foot and the output is converted to meters and metric tonnes. However, this can be confusing. We recommend matching units for product densities and dome dimensions.**

## Product

**Product Name.** Just what it says, it prints the input name for reference.

**Angle of Repose.** The user input angle of repose in degrees.

**Density.** The input product density and unit measure.

**Volume.** The total volume of the product cone and the frustum below the cone.

**Capacity.** The total capacity of stored product.

**Bushels.** An optional output if Units are set to “bu” to show the stored capacity in US bushels.

## Cone @

**Above Floor.** The distance above the floor to the base of the product cone. It is calculated using the angle of repose to measure a sloped line from the dome apex down to where it intersects the dome or stem wall.

**Radius.** The calculated base radius of the pile cone.

**Height.** The height of the product cone from the base where it intersects the structure to the dome apex.

**Slant Length.** The length of the sloped portion of the product cone.

**Lateral Area.** The surface area of the product cone.

**Volume.** The total cubic volume of the product cone

**Capacity.** The total storage capacity of the product cone itself.

## Portion above cone

**Remaining Height.** The height of the dome structure from the base of the product cone to the dome apex.

**Surface Distance.** The surface distance from the dome apex to the base of the product cone.

**Surface Area.** The surface area of the dome structure above the base of the product cone.

**Volume.** The volume of the dome structure above the base of the product cone inclusive of the cone and empty space around the cone.

**Empty Volume.** The estimated empty space between the product cone and the dome shell.

## Frustum below cone

**Frustum Height.** The height of the storage volume from the floor to the base of the product cone. If the product cone is smaller than the diameter of the structure the frustum height will be zero.

**Surface Distance.** The surface distance from the base of the product cone to the floor including the dome structure and stem wall.

**Surface Area.** The surface area of the dome structure below the base of the product cone including the dome structure and stem wall.

**Volume.** The volume of the dome structure below the base of the product cone including the dome structure and stem wall.

**Capacity.** The total storage capacity of the frustum.

## Floor

**Diameter.** The floor diameter is a circle representing the floor, stem wall, and dome base diameter.

**Radius.** The floor radius is half the floor diameter and is a useful number for various calculations.

**Circumference.** The floor circumference is the distance around the circle-shaped floor, stem wall, and dome base.

**Area.** The floor area is the area of the circle inscribed by the floor diameter.

## Dome

**Height.** The dome height is the distance from the base of the dome to the apex.

**Radius of Curvature.** All dome structures described by this calculator are a segment or “cap” of a sphere as defined by the dome’s diameter and height. The radius of curvature is the calculated radius of the whole sphere of which the dome is a portion.

**Surface Distance.** The dome surface distance is the length from the apex, following the dome curve down to the dome base.

**Surface Area.** The dome surface area is technically the dome’s lateral surface area from the base to the apex.

**Volume.** The dome volume is the cubic measure of the volume encompassed by the structure’s dome portion.

## Stem Wall

**Height.** The stem wall height describes a cylinder’s height with the floor diameter and the stem wall height. It connects the floor to the dome base. Leave the stem wall height set to zero (0) to remove the stem wall.

**Surface Area.** The stem wall surface area is the area of the cylinder formed by the stem wall.

**Volume.** The stem wall volume is the cubic measure of the volume encompassed by the stem wall cylinder.

## Total

**Height.** The total height is the overall height of the structure, as defined by the sum of the stem wall and dome heights.

**Surface Distance.** The total surface distance is the dome surface distance from the apex to base plus the height of the stem wall equaling the distance along the surface of the building from the apex to the floor.

**Surface Area.** The total surface area is the sum of the dome surface area plus the stem wall cylinder surface area.

**Volume.** The total volume is the cubic measure of the total volume encompassed by the complete structure.

## Overlays

An overlay is a scaled illustration to help convey the size, purpose, and scope of the calculated structure. They are for convenience only. No attempt is made to “fit” them inside the building or to determine their appropriate use for a structure. They are merely a visual aid.

**None.** The *none* option deletes the overlay.

**Person.** The *person* overlay is the default overlay. It is a person rendered at 6-feet (1.8 m) tall.

**Car.** The *car* overlay is a mid-sized sedan with a 6-foot (1.8 m) person standing beside it.

**BBall.** The *bball* overlay is the side silhouette of a standard American competition basketball court on a six-inch floor. We recommend setting the *level* parameter to 20.5 feet to show the standard clearance height required for a competition floor.

**Loader.** The *loader* overlay is a small front-end loader—6,000 pounds (2800 kg) operating capacity with bucket—approximately 8 feet (2.5 m) tall next to a 6-foot (1.8 m) tall person.

**Heavy.** The *heavy* overlay is a large front-end loader—66,000 pounds (30,000 kg) operating weight—approximately 12.5 feet (3.8 m) tall next to a 6-foot (1.8 m) tall person.