The length of the annulus or the length of the low-density fluid and mud density of the lost circulation can be calculated based on the annulus capacity behind the drill collar. Suppose the lost circulation volume is smaller than the annulus volume against the drill pipe. In that case, the length of the annulus (i.e., …
Keyseating is one of the primary reasons for fishing during drilling. A key seat is a small hole cut into the well bore wall due to the movement of the downhole drilling assembly. This cut usually happens when the hole changes direction, the hump of doglegs, in undetected ledges near washouts. A part of the …
In the drilling industry, the rate of penetration (ROP), also known as penetration rate or drill rate, is the speed at which a drilling bit breaks the rock under it to deepen the borehole. It is generally measured in feet per minute or meters per hour. Generally, ROP increases in fast-drilling formations such as sandstone …
Drilling oil and gas wells can sometimes encounter a common issue called the drill pipe twist off. This problem can have a direct impact on the overall well cost and duration of the drilling process. In this article, we will explore the primary causes of this problem and discuss ways to prevent it. What Is …
The decision to fish or not must be weighed against a need to preserve the wellbore, recover costly equipment, or comply with regulations. Each choice is fraught with its costs, risks, and repercussions. This is why learning how to calculate the economic and optimum fishing time is important. Before committing to a specific course of …
A mechanical thruster tool is a piston device that can be included in the drill string above the drilling bit or a motor. It is a specialist tool originally developed for slim hole drilling and is now available in sizes from 1-11/16″ up to 9-1/2″ in diameter. As the pressure inside the thruster increases, it …
During drilling and workover operations, the consequences of leaks with sour gas or crude may be devastating. Drilling H2S-bearing formations poses one of the most challenging and dangerous problems to humans and equipment. Personnel can be injured or even killed by relatively low concentrations of H2S in a very short period. Equipment can experience terrible …
In general, differential sticking is a situation that may happen during any stage of drilling the well and cause the drill string or casing pipe to be stuck (no upward or downward movement). It actually happens when the hydrostatic pressure, ph (which acts on the outside wall of the Pipe), is more than the pore …
Oilfield Magnetic fishing tools consist of permanent or electric magnets running on a conductor line. The outer edge of permanent magnets has circulating ports, which wash away fill and cuttings and make contact with the fish. A brass sleeve is fitted between the magnetic core and the outer body to avoid any drag on the …
A drilling rig job requires a wide range of skills and knowledge. Common roles include rig supervisor, tool pushers, drilling engineers, drilling deck workers, mud engineers, drillers, and mechanics. Drillers are responsible for operating the rig types safely and efficiently and conducting maintenance on the equipment. Mud engineers oversee the mixing of fluids used in …