Sonic rigs are known to employ an advanced form of drilling.
It makes use of resonant, high-frequency energy created inside the sonic head, increasing its efficiency in creating a borehole. By this measure, the casing or core barrel will be able to seamlessly advance into the subsurface formations.
In the course of a drilling process, the resonant energy will be relayed to the drill string and directed to the bit face. This occurs at various sonic frequencies, and alongside that the rotating drill string distributes the energy evenly, impacting the bit face in the process.
Most of the time, sonic drills are more associated with a rotary vibratory drill. It can efficiently handle high drill speeds and can accomplish tasks like continuous coring. Such a kind of drilling task is almost impossible to carry out if you are just going to use some other drilling tool.
At first, glance, if you don’t know anything about it, you’d think that the sonic drill looks like any traditional mud rotary drill rig. The primary distinction it comes with can be found in the drill head. It is slightly bigger as opposed to a standard rotary head. The drill head usually houses the mechanism needed to sustain rotary motion. It also comes with an oscillator that induces high-frequency force that will be superimposed on the drill string.
As for the drill bit, it will vibrate physically in an up and down fashion, aside from being rotated and pushed down. These three forces combined make drilling proceed rapidly with almost every kind of available geological formations, including the majority of rock types.
In overburden cases, the vibratory action will induce the soil particles around it to somehow soften and fluidize. When this happens, there is going to be a seeming effortless penetration. The drill bit in rock is likely going to induce rock face fractures. If this happens, the production of rock dust is likely to occur and will also significantly help in facilitating the drill bit to advance.
In many instances, you can accomplish rock coring and drilling without using any kind of drilling fluid whatsoever. If you are working on a qualified environmental drilling project, it is one of the most important requirements you will need to keep in mind. Drill mud, compressed air, and plain water can be taken advantage of to take away the cuttings and further enhance the speed of the drilling operation, all depending upon which the drilling machine is originally intended for.
The oscillator will be driven by a hydraulic motor. Besides, balance weights are also used to create a high sinusoidal force which is eventually transmitted to the drill bit. And to restrict the alternating forces to the drill string, an air spring can be incorporated also. The frequency can vary in this regard so that it can become suitable for operating conditions. Generally, the frequency will range between 50 to 160 Hertz or cycles per second.
For comparison purposes, in many countries today, an ordinary or average household would normally have 60 Hertz. A frequency range of this magnitude is falling within the lower range of sound vibration, which the human ear is capable of detecting and hearing. Hence, this type of rotary-vibratory drilling equipment earned the moniker sonic rig drilling.