Several drilling methods and machinery are available for different drilling needs. Shallow drills can be done hydraulically, for instance, while deeper holes may require diesel power. Different drilling diameters can also be achieved for different purposes. One drilling method that has fast risen to popularity is the wireline drilling method. Wireline drilling rods are designed specifically for the wireline drilling process. In this process, the diamond drill rods carry out drilling in a regular manner but the core is collected differently. With many drilling techniques, drilling has to be discontinued and the rods removed from the hole to facilitate core removal. After every removal, the drilling rods are then lowered back into the hole and drilling resumes. Since drilling rods range between one and three meters, boring a kilometer or two into the earth can be quite arduous.
Wireline Drilling is a process whereby the drilling apparatus expels the core without having to remove the diamond drilling rods. The core is expelled by use of a feature called an “overshot.” The overshot is attached to a wireline, and it winches the inner tubing that was used to capture the drilled core, out of the hole. Empty tubing is then lowered back. All this happens while the diamond drilling rods are still in position down the hole. Once the tubing is back, drilling resumes. Besides a considerable reduction in drilling time, there are two other advantages to this drilling technique.
When drilling in areas prone to caving, wireline drill rods would be the best option to use. The outer barrel of the drill and the drill string remain firmly in position while the inner tubing removes core substance after every run. The material in the walls of the hole does not, therefore, get disturbed and loosen leading to a cave-in.
Increased bit life
In situations where the drill bit has to be removed after every run for core expulsion, the bit often loses its drilling “strength” or becomes dull quicker. The loss in “bit-life” can be attributed to constant re-drilling necessary whenever the apparatus is on re-entry to continue drilling. Cave-ins, especially, contribute to this loss of life. In the wireline drilling technique, the diamond drill rods are not subjected to this need for re-entry drilling. They will, therefore, achieve more drilling over longer periods of time before requiring change.
Finally, the less drilling time and effort accorded by wireline drilling technique translates to greater drilling distances. Kilometers of earth can be removed quite easily with this method as opposed to other methods.