subshaft

subshaft

(ˈsʌbˌʃɑːft)
n
a secondary shaft in a mine
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References in periodicals archive ?
The program is based on the master-slave synchronization, subshaft torque feedback to the principal shaft.
Subshaft 1, previously the Short Subshaft (SSS), is to be deepened by 219 m from 113 Level to 123 Level (3,737 m below datum).