Borehole Solutions’ Complete Guide To Sonic Drilling

by | May 8, 2020

In a world full of fads, trends and phases, the drilling industry has proved no different. There’s been a trend in recent years for geotechnical site investigation companies to err towards using sonic drilling rigs. But why is this? Unlike more conventional auger and rotary drilling setups, sonic drilling offers a cleaner, more efficient alternative. Here at Borehole Solutions, we wanted to take the time to explain why sonic drilling offers an attractive augering alternative. After reading this blog, you’ll be left wondering why more geotechnical site investigators don’t use this technique; these rigs really are the present and the future of drilling.

Modular sonic drilling unit
Our modular sonic rig in action on the coastline.

What Is Sonic?

Sonic drilling is an advanced soil penetration technique which uses high-frequency energy generated inside a sonic head (in most instances, a Sonicor 50k drill head) to advance a core barrel downwards through the required substrate. The vibrations emanating from within the sonic head have a liquefying effect, loosening the surrounding soil structure’s integrity and allowing for smoother drilling as a result. Once the core barrel has been advanced, the rig’s telescopic casings are placed over the core barrel. This then enables core retrieval to take place with no risk of collapse, even in more unconsolidated substrates. Whilst these drilling rigs can be used in more solid formations, they undoubtedly work best in overburdened conditions. Even when drilling through these harder strata, there’s still rarely any refusal; instead, it just takes a slightly longer drilling time.

The Benefits Of Sonic Drilling

The benefits of this drilling method are manifold and far outweigh any potential limitations that they may encounter. These benefits include, but are not limited to:

Safety

Over the decades, traditional geotechnical site investigations have often brought about significant personal injury to those operating them. These injuries can include broken digits, fractures and major cuts. A lot of this danger stems from clothing catching on the components of the rig – auger flights, for example. The smooth rods and casings, and the hands-free operating systems utilised in sonic drilling rigs mitigates a great deal of this risk. This drilling method requires fewer workers on-site, and thus there are fewer people at risk of injury in the first place. Sonic drilling rigs feature: safety cages, braiding for hoses, guarding measures, counter balance valves, non-skid walking platforms and much, much more.

Speed

When compared with conventional rotary drilling, sonic drilling rigs operate up to 400% more quickly. This is in no small part down to the high-frequency oscillations within the sonic head; these oscillations mean that the drill bit can carve through unconsolidated formations with unparalleled ease. The speed doesn’t just come in the form of the drilling itself. It comes in the fact that unlike other equipment, sonic drilling rigs can carry out continuous coring.

Clean

One of the main issues stemming from site investigations is the waste that’s produced. Investigation derived waste (IDW) can have ecological impacts, contaminate and therefore corrupt sample integrity. One of the perks of this improved drilling cleanliness, is that the integrity of the core samples returned is incredibly high using sonic drilling rigs, when compared with other geotechnical methods.

Environment

The reduction in waste paired with a much quicker on-site operation means that sonic drilling is a more environmentally-conscious geotechnical methodology. A shorter time spent on-site means less energy is used in running the power-hungry geotechnical equipment. The rig itself is also more efficient than conventional rigs. The reduction in friction upon the drill bit and drill string means that less energy is required to operate the drilling rig.

Versatility

There aren’t many site investigation methods as flexible and versatile as sonic drilling. No two site investigations are the same, the amount of variability within each and every job means a high degree of adaptability is required. Rubber caterpillar tracks are fitted to these drilling rigs. This ensures a high degree of manoeuvrability, even in tough conditions. The technology utilised within these rigs may be complex, its operation is much simpler and is carried out from an on-board master console. Its simplicity of use is not to be confused with lack of training or skill. All of Borehole Solutions’ drillers are completely qualified in the relevant sonic drilling qualifications and have the utmost competence and proficiency in their trade.

Borehole Solutions offers an array of drilling services, from window sampling to pit digging, restricted access drilling to cable percussion. However, it is our sonic drilling rigs and services of which we are proudest. Whilst conventional rotary and percussive drilling options all have their perks, there are few drilling options as versatile as sonic drilling. So, if you’d like to find out more about Borehole Solutions’ sonic drilling services, then get in touch! Call today on 01733 200 501.