Well Completion Basics
What is Completions Engineering?
Completions engineering is the process of completing drilled and cased wells and placing them on production.
Completions Engineers may also look after a number of other related process that occur over the life-cycle of a well such as workovers, re-completions, remedial interventions and abandonments.
Completions Engineers will work closely with the drilling team during well planning to ensure their planned operations can be accommodated by the well design.
Although completions will vary widely depending on the field and reservoir generally once the well is drilled and cased completions engineers will plan, cost and execute a program to perforate, test, stimulate and place the well on production to begin producing the oil and gas reserves.
What is a Completion?
A completion is an operation on an oil and gas well to open up the reservoir to production.
An initial completion occurs after the drilling rig is moved off location. The wellbore is isolated by casing and cement and/or a packing device preventing any oil or gas from entering the wellbore and flowing to surface.
Completions methods vary widely by area and reservoir type. In general a zone of interest is picked from the open-hole logs, which show signs of oil / gas.
A perforating gun is run into the wellbore, a controlled set of explosives (charges) are set off perforating the casing, cement and reservoir. This allows the oil and gas to flow into the wellbore and to surface.
Often stimulation is need in order for wells to flow economically. This can include pumping acid or hydraulically fracturing the reservoir. If the reservoir is under-pressured artificial lift equipment may need to be installed to aid bringing the hydrocarbons to surface.
What is Hydraulic Fracturing?
Hydraulic fracturing is the act of pumping fluid downhole at a high enough pressure to breakdown or fracture the rock. Sand or proppant is then pumped in order to ensure the fractures remain open during flow-back and production.
How do you drill an oil or gas well in the first place?
Before you can complete a well, it has to be drilled first. Drilling and oil and gas well can be a long and complicated process, depending on the location and field you are drilling in. We wrote an article summarizing the entire process. Read more →