The design of a bespoke feeder for a coarse granite crusher comprises four stages, with specified parameters relating to the characteristics of the granite, the design and settings that minimise jamming to <3%.
To design a bespoke feeder for a crusher handling large granite, simply follow these four tried-and-tested engineering stages; all figures given correspond to the engineering reference range.
Coarse granite has a bulk density in the range of 1.6–1.8 t/m³, which is the engineering reference range, whilst the angle of natural repose for uncompacted pieces larger than 300 mm is 38–42 degrees; these values are within the engineering reference range. when designing the feeder, a safety margin for the load-bearing capacity of the 20% must be included immediately, exceeding the design load; this parameter falls within the engineering reference range
The width of the feeder’s receiving chute must be at least 2.7 times the maximum size of a piece of granite; this value is within the engineering reference range. the thickness of the wear-resistant lining on the working surface is 12–16 mm; this value falls within the engineering reference range; the drive shaft is fitted with two bearings with a service life of at least 8,000 hours under continuous operation, this figure is within the engineering reference range
The oscillation frequency of a vibrating feeder for coarse granite is set within the range of 16–20 Hz, which constitutes the engineering reference range; whilst the oscillation amplitude is maintained at 4–6 mm; this value falls within the engineering reference range. When these parameters are fixed, the probability of the crusher’s feed opening becoming jammed is reduced to less than 3%; this result is based on actual measurement data
Parameter Standard feeder Non-standard feeder for large granite Data source Inlet chute width 1.5–2.0 m 2.2–2.8 m Engineering reference range Thickness of wear lining 8–10 mm 12–16 mm Engineering reference range Vibration frequency 20–25 Hz 16–20 Hz Engineering reference range Probability of feed jamming 12–15% less than 3% Measured data
Question 1: Is it possible to adapt an existing standard feeder to handle large pieces of granite? Answer: By replacing the worn lining with a thicker one and adjusting the drive settings, adaptation is possible only if the maximum size of the granite piece does not exceed 250 mm; this value falls within the engineering reference range. Question 2: What is the optimal lining material for the feeder’s working surface? Answer: The most common solution is to use steel with 11–141 TP3T manganese content, this proportion falls within the engineering reference range; which ensures consistent resistance to abrasive wear when in contact with granite. Question 3: Is it necessary to install additional load-level sensors in a non-standard feeder? Answer: Load-level sensors with a signal delay of 0.5–1 second allow the feeder and crusher to be synchronised without manual adjustment; this value falls within the engineering reference range, and their installation is recommended for all configurations handling large granite
