A bulk belt conveyor supports a loaded upper run on trough-forming rollers and returns the empty belt below. The animation shows both runs and the trough in end view. Use the calculator to relate entered load area and speed to volume and mass flow.
Bulk Belt Conveyor Calculator
Enter loaded cross-sectional area, belt speed, bulk density and pulley diameter. Explore material flow on a level conveyor.
Volume = 3600Av; mass flow = 3.6Avρ; material loading = Aρ; pulley rpm = 60000v/(πD)
A is loaded area in m², v is belt speed in m/s, ρ is bulk density in kg/m³ and D is contact diameter in mm. Results are m³/h, metric tonnes/hour, kg/m and rpm. The loaded area must come from measurement or a suitable capacity calculation; it is not inferred from the illustrative trough.
- Horizontal conveyor with uniform loading and steady flow.
- Loaded area is supplied directly; no CEMA trough-area table is embedded.
- Material and belt travel together without slip.
- No calculation of drive power, tension, structural strength, incline derating or safe capacity.
Construction: Hiscox movement 1224. Capacity is area × speed × density; pulley speed follows circumference.
How the conveyor carries material
The head pulley drives the continuous belt. The loaded upper run travels toward discharge, while the empty lower run returns toward the tail. Carrying rollers support the upper run and form its trough; lower rollers support the return.
The end-view inset follows Hiscox movement 1224: a horizontal central roller and inclined side rollers turn up the belt edges to retain bulk material. The side view shows the circulating belt, head and tail pulleys, frame and an illustrative discharge stream.
The animation is a construction and flow illustration. It does not simulate particle collisions, belt sag or the exact material release trajectory.
Applications
Bulk conveyors move materials such as aggregate, grain and ore along a defined route. Belt width, trough profile, material properties, loading conditions and route geometry all affect the usable capacity. This calculator accepts the loaded area directly for a level-conveyor flow estimate.
Flow and pulley-speed equations
Volume flow = 3600 A v in m³/h. Mass flow = 3.6 A v ρ in metric tonnes/hour when density ρ is kg/m³. Material loading = Aρ in kg/m. For a no-slip pulley with diameter D in mm, speed N = 60000v/(πD) rpm.
The loaded area is the cross-section actually occupied by material. Belt width alone is insufficient to establish it. Obtain the area from a suitable trough-capacity method or measurement.
Worked example
For A = 0.10 m², v = 1.5 m/s, ρ = 1600 kg/m³ and D = 500 mm: volume flow is 540 m³/h; mass flow is 864 t/h; material loading is 160 kg/m; and head-pulley speed is 57.3 rpm.
At zero belt speed the flow and pulley RPM are zero, while material loading remains 160 kg/m because the stationary belt can still carry its load.
What this estimate does and does not establish
Increasing speed increases ideal throughput for the same loaded area and density. Increasing pulley diameter reduces required RPM at the same belt speed. Neither result establishes the conveyor’s permissible speed or load. Actual design also addresses tension, drive power, transfer points, tracking and the supporting structure.
Calculator questions
Where does the loaded area come from?
Use a measured cross-section or a capacity method suited to the belt width, trough and material surcharge profile. The inset is illustrative.
Why does density change mass flow but not volume flow?
The same occupied volume contains more mass when the bulk density is higher.
Why does pulley diameter change RPM but not flow?
Belt speed is entered independently. A larger circumference requires fewer revolutions to produce that speed.
Does the displayed flow include an incline correction?
No. The calculation assumes a horizontal conveyor with steady uniform loading and no slip.
References
- Gardner D. Hiscox, Mechanical Movements, Powers, Devices and Appliances, movement 1224, printed page 302: trough-forming carrying rollers and a horizontal return.
- Jealco conveyor belt speed and capacity equations: area, speed and density relationships and the no-slip pulley speed equation.
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