Well intervention, or well work, involves operations carried out on an oil or gas well to alter, manage or diagnose well health. At any stage in the oil or gas well's productive life, well intervention can be used to help maintain optimal operating conditions. There are various types of well intervention, each meant to address specific concerns of a particular well.
When an oil or gas well is young, for example, it may be useful to manage its pressure and flow by adding equipment or otherwise altering the existing well. Well intervention might be necessary in such a case to safely and effectively apply the desired changes and manage or increase well production. Older oil or gas wells might require periodic cleaning or other maintenance, and well intervention also is often used for this type of management strategy.
One example of well intervention is known as pumping, in which chemicals are pumped into the well to encourage resource production or clean up extraction byproducts. Another important type of intervention is the workover. Sometimes, so many of the parts of an oil or gas well need to be replaced at once that the entire operation, or a significant portion of it, must be replaced. This is a potentially important aspect of subsea drilling, which may be considered more risky and costly than land-based drilling.
Equipment and wells will probably change over the wells' operational lifetime, so managing the flow and the equipment within a well may be necessary. Well head maintenance, for instance, usually involves a number of intervention strategies being performed as routine maintenance and scheduled procedures being carried out on the well head specifically. Other concerns that might require well head maintenance can include removing unwanted water, encouraging resource production and removing extraction byproducts.
In addition to routine maintenance, various tests are often necessary when managing a well. These tests can increase an understanding of the oil or gas flow, observe geologic characteristics and generally help crews understand well health. In general, these tests and management strategies are usually meant to improve the productivity of the well at any stage in its life.
Dwindling land-based oil reserves have increased the importance of subsea well intervention, which takes place in oil and gas well operations off the coast. Like many other types of well work, subsea operations are usually meant to maintain or improve productivity. Many issues associated with subsea drilling, such as excess water and sand particles, can be managed by subsea well intervention.