September 26, 2013
tubing load cells are used for measuring the insertion force of
small diameter (typically 0.5 to 4.5 inch) stainless steel tubing that
is inserted into the borehole / wellbore at the wellhead. A borehole
is any hole drilled for the purpose of exploration or extraction of
natural resources such as water, gas or oil where a well is being produced.
The coil tubing (CT) is usually installed when the well, which has been
drilled, is deemed ‘viable’ and will produce the natural resource in
a productive and economic manner. Coil tubing provides intervention
allowance of vertical, horizontal, highly deviated, and live wells(1).
Adding the coil tubing allows prolonged fluid extraction (and/or insertion)
from/to the wellbore. Note: Wellbore is often used interchangeably with
drill hole or borehole, though typically "borehole" is referred to in
ore mining, exploratory drilling, pilot holes for installing piers or
underground utilities, or any other of a number of single use hole drilling(2).
wellbores can be thousands of feet in depth/length. Estimates of the
longest wellbores are conservatively, up to 17,000 feet, and typically
up to 24,000 feet in depth, although the deepest is located in Russia:
Kola Superdeep Borehole(3) at over 40,000 feet.
Coil tubing is
forced into the wellbore via a “coil tubing injector head” in the field
or offshore – an insertion process which has been used for decades,
with typical insertion rates at 50 to 100 feet-per-minute.
1 Coil tubing truck carrying a large spool of 2" tubing with the injector
head (right side). Courtesy Stewart and Stevenson Inc. 2013
Posted October 10, 2013