Drill with hammering mechanism (DHM) (05-07)
This study considered the implementation of hammering/impacting mechanism in rotary coring drills, to increase their efficiency when drilling hard rock.
In a Drill with hammering mechanism (DHM), a cam-hammer mechanism, that uses the sudden release of a compressed spring, produces 1 Joule impact energy at a nominal frequency of 1 Hz. The challenge of the mechanism design and realisation laid in the very limited room available for its implementation, mainly the reduced diameter (24 mm max. available for the accommodation of the mechanism).
For the test a dedicated drill Test Equipment and a set of mock-up drill tools (both commercial and on purpose made) were used.
The prototype was manufactured and extensively tested in different types of hard materials and in different operative condition.
The DHM prototype has proven its effectiveness by drilling into granite (compressed strength 160 MPa), and getting samples, with low thrust applied (e.g. 100N) and with very low power consumption (e.g. 5-10W) at penetration speeds of about 0.02 mm/minute.
This study was performed by Galileo Avionica Milan teaming with Helsinki University of Technology.
Last update: 2 February 2011