Drill String

A drilling battery is a tool that is used to drill deep hole holes in the ground in order to locate and extract oil or other resources. The construction of this device allows for rapid drilling and at the same time to extract large amounts of rock and mineral from a digging site. Mud is also injected down through the drilling battery to cool the tip while it is moving and to soften the surface that is boring through, reducing the likelihood of an improper cutting and increasing the overall bit time. A medium drilling string extends 15,000 feet (4,572 m) into the ground once mounted on the ground and up to 30,000 feet (9,144 m) or more when built offshore,

Within the drill battery assembly, there are four main components: lower hole mounting (BHA), transition tube, drilling rods and drill bit subs. The BHA is the stabilizing system that consists of the same tip and massive heavy rods that apply enormous amount of force down to facilitate drilling. A passage pipe connects the heavy rods to the actual drill pipe, and together these two components provide the necessary stability to ensure that the tip remains solid at such drastic depths. Drilling rods are also the majority of the length inside a drilling column, so they must be constructed using specific chemical compositions and forged at extreme temperatures.

Most components within a drill column are constructed at 31 or 46 feet (9.4 or 14 m) intervals, and two to four of them are combined to do what is termed a stand. Each substrate is then lowered into the ground before drilling initiated, in order to ensure that the drill always stays within perfect alignment. Similarly, they are removed from the ground before the drill is extracted.

Sometimes, the stands can get stuck and become difficult to remove, and specialized recovery tools called drill string jars and resonant vibrators are used to remedy this otherwise difficult situation. These methods are normally implemented by experienced oil companies. Technological advances discovered during the mid-20th century have made drilling strings much easier to handle.