Well completions are typically defined as the point in time that a well has been officially recognized as being both commercially lucrative and viable. Most industry experts consider this exact moment as being when the drill head meets with the reservoir. The monetary benefits one can expect from a well depends entirely on how the well is completed. There are three things which must occur for the well to be completed successfully. Firstly, the wellbore must allow gas or oil into the physical well itself, so that it can be pumped out. Secondly, water must be kept out of and away from the well, Thirdly, the formation cannot at any time collapse on itself into the well.
There are several different types of completions which can apply to a drilling situation. They are:
Open-Hole- These types of completions require absolutely no liners or productions casings. Instead of these traditional pairings, the fluid enters the well through an intermediate casing which allows the fluid to freely flow up to the surface. With this production method, slotted liners may even be used as long as there is no risk of stability to the wellbore.
Perforated- This is far and away the most common method of completion that is used today by major drillers. This method entails the production casing to be pierced in strategic locations so that the well fluid can freely flow to the surface where it is then drained.
Offshore well completion is quite similar to its ground-based completion methods. On offshore oil rigs, the wellhead is typically found on the platform deck. This style of offshore completion is known as a surface completion. If the drilling is taking place on platforms floating on the ocean or in very deep water, the wellhead is based on the floor of the ocean and it is known as subsea completion.
One of the most successful companies in business today which engages exclusively in deepsea drilling is called PRT Offshore. When formations are presenting problems in such an environment, the liquid must often undergo very pricey treatments so that the liquid behaves in the manner in which it is normally supposed to. These treatments include fracturing areas between the rock so that a greater flow can occur. These can be done either with more drills or explosives. The explosives are placed by demolition experts to avoid any potential natural backlash.