Rock sorting

The QGHL houses a rock-sorting facility with sieve fractionation tables and a weigh-belt rock sorting machine which sorts rocks into the pre-set weights for the construction of a scale model.

About

  • We use the sieve fractionation table for processing bulk quantities of model-scale rocks. It is beneficial for basin projects with large rock seawalls or breakwaters. QGHL staff can configure the table with screens of different sizes holes to separate rocks of different sizes, each designed to separate rocks of specific dimensions. The currently available screen sizes range from 10mm to 75mm, and custom screens of smaller or larger sizes can be manufactured upon request.
  • The weigh-belt sorting machine uses a load cell to measure the weight of individual rocks and then can separate them into up to six weight bins through a flap-paddle rejection system. The rock sorter is capable of sorting rocks that weigh between 10g and 1000g. The sorting machine is reasonably quick, able to weigh approximately one rock per second. It is often used to grade all rocks for flume models and quality-checking samples of size-sorted rock grades obtained from sieve fractionation.
  • Rock shape sorting and checking is conducted manually, with rocks inspected by QGHL staff to ensure they conform to the required blockiness, shape, and aspect ratios.