Method for boring sleeved vertical bores involves using support frame fitted to the boring shaft and connected to the boring tube via removable bolts to enable the boring bit to clear out the inside of the tube

摘要

A simple method for boring sleeved vertical bores involves using a support frame (1) welded to the shaft of the boring bit and secured to the outer tube (6) via removable/retracting bolts (4) gripping into holes in the top of the tube. The tube is driven into the ground by the boring action. The spoil inside the tube is subsequently removed by the boring bit after releasing the bolts.