Cleaning
can be achieved using a Dawson hydraulically operated cleaner or by men
with shovels. Within six to nine months, the investment in a Dawson mechanised
hydraulic cleaner becomes the most economical method. The choice is similar
to digging a trench by hand or using a hydraulic excavator.
The cleaner consists of a Hydraulic Drive Motor and a Reduction Gear Box driving a large diameter bearing onto which is mounted a quick change Shell to suit the Auger diameter and pitch being used. The auger flight passes through the shell where the spoil is removed by hydraulic power.
As the auger is being withdrawn from the ground during the concrete injection, the cleaner shell is hydraulically powered down the auger flight removing spoil by means of a helical blade guided by a roller inside the shell.
A free-wheel valve enables the cleaner to be activated briefly during drilling to back the cleaner up the flight. This means there is no continuous power requirement during drilling allowing the total available hydraulic power to be used where it is needed most…..at the drill!
The cleaner gears and drives are fully enclosed and sealed to prevent the ingress of contamination, retain lubricants and protect against the potential hazard to personnel.