Characteristics of Bulk Materials The information contained within this section has been accumulated over a period of several years from various sources that we have deemed reliable. Some entries are for materials that we have either stored or conveyed and for which, the information shown was obtained directly from the producer or user. We believe that in most cases, you may use this data base for the purpose of preliminary sizing and early stage system design. However, Cambelt International makes no guarantee of accuracy or completeness. You must always verify the actual material characteristics with a knowledgeable source prior to making your conclusions firm and/or setting into place your final design parameters. Please reference the materials in the data base to the table below:
| Flow | Very free | Free flowing | Average | Average | Sluggish |
| Angle of Surcharge | 5° | 10° | 20° | 25° | 30° |
| Example |  |
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| Angle of Repose | 0°-19° | 20°-29° | 30°-34° | 35°-39° | 40° up |
| Characteristics | Uniform size, very small rounded particles, either very wet or very dry, such as dry silica sand, cement, wet concrete, etc. | Rounded, dry polished particles, of medium weight, such as whole grain and beans. | Irregular, granular or lumpy materials of medium weight, such as anthracite coal, cottonseed, meal, clay, etc. | Typical common materials such as bituminous coal, stone, most ores, etc. | Irregular, stringy, fibrous, interlocking material, such as wood chips, bagasse, tempered foundry sand, etc. |
