Tuesday, May 20, 2008

Basic Drilling Concepts: Perforation




After the production hole is cased and cementing, now the well is ready to be perforated. Perforation gun is conveyed down the hole with the use of either wireline, drill pipe or coiled tubing. Wireline can be conveyed typically for wells with an inclination of <60 deg. This is because it is lowered by gravity.

Explosives are carefully positioned on the gun based on spf (shots per foot). Phasing is also used to describe the arrangement of the explosives. The charges are detonated either hydraulically (via drill pipe or coiled tubing) or using current (via wireline).

Different types of explosives will determine size of perforation tunnel, which connects the wellbore to the reservoir and temperature rating.

2 comments:

Wata said...

Salam. I always wondered what the actual risk was to use radio energy generating equipment while a perforation exercise was underway. Since Europe has figured out that cellphones do not pose a risk to avionics (a big perception change), is there the same thinking about radios?

opcharlie said...

yes there have been serious discussions abt it but knowing the industry, we will be the last the adopt the technology! SLB has devised guns that do not trigger on radio signal but they're expensive.