TUGAS INTERNET

PERMANENT PACKER

Packers
The packer forms the basis of the cased-hole completion design. The packer is a
sealing device that isolates and contains produced fluids and pressures within the
wellbore to protect the casing and other formations above or below the producing
zone. This is essential to the basic functioning of most wells.

Uses of packers
In addition to providing a seal between the tubing and casing, other benefits of a
packer are as follows:
o Prevent downhole movement of the tubing string
o Support some of the weight of the tubing
o Often improve well flow and production rate
o Protect the annular casing from corrosion from produced fluids and
high pressures
o Provide a means of separation of multiple producing zones
o Limit well control to the tubing at the surface for safety purposes
o Hold well-servicing fluid (kill fluids, packer fluids) in the casing
annulus.

Packer components
Packers have four key features:
o Slip
o Cone
o Packing-element system

Packer classification
Production packers can be classified into two groups:
' Retrievable
' Permanent.

Permanent packers
Permanent packers can be removed from the wellbore only by milling. The retrievable
packer may or may not be resettable, but removal from the wellbore normally does
not require milling. Retrieval is usually accomplished by some form of tubing
manipulation. This may necessitate rotation or require pulling tension on the tubing
string. The permanent packer is fairly simple and generally offers higher performance
in both temperature and pressure ratings than does the retrievable packer. In most
instances, it has a smaller outside diameter (OD), offering greater running clearance
inside the casing string than do retrievable packers. The smaller OD and the compact
design of the permanent packer help the tool negotiate through tight spots and
deviations in the wellbore. The permanent packer also offers the largest inside
diameter (ID) to make it compatible with larger-diameter tubing strings and monobore
completions.