Experimental research on the rock fragmentation loads of a water jet-assisted cutting head

Abstract

A test bed for rock fragmentation by cutting head was developed to investigate the load of water jet-assisted cutting heads. In this test bed, water jet was pumped into the center of the conical pick. In the case without water jet, the characteristic index of the cutting torque and pulling force increased with the rock compressive strength exponentially. No obvious relationship was observed between the characteristic indexes of the cutting torque and the rock compressive strength for the case with water jet, but the effect of the water jet on the pulling force of the cutting head was relatively stable. The cutting torque and pulling force were decreased by 20 % to 40 % when the rock compressive strength was lower than the water jet pressure. However, the water jet that assisted in rock fragmentation was less effective when the water pressure was lower than the rock compressive strength. The ratio between water jet pressure and rock compressive strength can help recognize the efficiency of water jets for rock fragmentation by cutting head.