Drill rigs operate with the help of their drill string and their high-speed rotation makes it possible. As for the drill holes they create, they seldom come greater than 300mm to a maximum diameter of 600mm.
The slower speed is one of the distinct characteristics of piling rigs, capable of creating boreholes in 300 to 1200 mm diameter piles.
These dimensions can reach up to 2500mm. This operational guidance note is not inclusive of the driven piling operations (drilling or piling operations here does not work by virtue of rotation).
With this, we can cover a sundry of activities such as assessment work involving samples or cores at depths to assist with the handling of the foundation design, looking for mineral and water resources, designing routes for tunnels, and developing geothermal systems of energy.
But there are also other purposes such as soil anchoring and grouting in rock-bolting, unstable areas. Most of the time, rotary drill units are assisted or propelled by sonic wave applications or powered impact. Some rigs can be mounted on a lorry and the drill can be put up within the body, centrally, which can double as a lab area.
Keep in mind that the piling rig provides the force that will drive the drill string straight into the ground by its rotational movement or make connections that will not be covered in this guide. A handful of geotechnical drilling rigs can be made to work in the horizontal and vertical planes.
You can also incline them between the two, which goes to show that regardless of orientation, guarding is practicable. In horizontal or inclined applications, the full rotary drill-string length that is within.
Other purposes include grouting and soil anchoring in areas that are considered as unstable, de-watering, and rock-bolting. Most of the time, rotary drill units are assisted either by sonic wave applications or powered impact.
Some rigs can be mounted on a lorry and may be centrally installed within the body which also doubles as a lab area. Note that drill rigs that are pushing the drill string down into the ground using rotation motion to crack the ground or make connections are not subject to this guidance.
Many geotechnical rigs can be used to work in the vertical and horizontal planes or inclined between the two; guarding is practicable in all orientations. Either in vertical or horizontal applications, guarding of the entire rotary length drill-string is a must.
For geothermal work, drill mast attachments can be attached to excavators and they, too, need a good amount of guarding. When you fit a geothermal drill rig with auxiliary augers, this is seen as a special situation here. They are fitted outboard of the auger string or main drill.
The auxiliary augers will only be used in anchoring the rig to the ground. They are ground screwed at a very slow rate, much slower than 30 rpm. By this measure, the vertical load can be allowed on the main drill to be increased sans the need to lift the rig off the ground. There is no need to guard auxiliary augers for this purpose.