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Oilfield Technology
June
2015
production become a social responsibility to address a growing
global demand.
While many companies are struggling to find markets for the
services they offer, Welltec® has continued to deliver through
this economic flux. The company’s stated goal is to go beyond
expectations by changing how the industry operates; specifically,
it provides operators new ways to carry out traditional jobs by
optimising processes and using light, yet powerful tools driven by
methods designed to improve efficiency, safety, and sustainability.
For the past 20 years, e‑line tools and interventions have been
shaping the industry, and the latest versions of these tools have
recently shown their worth to operators in the field.
Thebeginningof e‑line interventions
Nearly 20 years ago, the Well Tractor® was first deployed into
complex horizontal wells. At the time, this system represented a
paradigm shift for the industry as a small, lightweight intervention
method, run on e‑line, that could replace larger, heavier, more
intrusive and complicated methods. Upon its introduction,
the system provided reliable conveyance to supplement these
approaches, becoming a natural extension of e‑line. Tractors now
routinely complete thousands of jobs a year due to increased
efficiency, safety and lower cost to the operator.
An e‑line deployed, robotic device, the Well Tractor carries out
operations throughout the length of the wellbore regardless of the
deviation and extension. In particular, it is able to apply enough
force to push large toolstrings to the end of the wellbore and move
past washouts in open hole operations. The system universally
runs all third party systems, fitting hole sizes from 2.2 in. to 22 in.
It enables coiled tubing, e‑line, and even slickline operations,
providing cost-effective conveyance in all environments.
A significant advantage it provides is the ability to overcome
the challenges of highly deviated wells by driving tools all the
way to the toe of the wellbore without the use of additional fluids
introduced into the wellbore. The e‑line tool circumvents the high
costs associated with rigs and is able to mobilise more quickly,
run in and out of the well faster than alternative methods, and
mitigate HSE risks by requiring fewer people at the wellsite while
in turn allowing for more sustainable operations in terms of the
environment and asset management.
Sustainableoperations
This technology also enables an expansive portfolio of services.
Running solutions for deployment, mechanical, clean‑out, milling,
completions, RLWI, and diagnostics, the Well Tractor helps
operators realise the full benefits offered by e‑line tools, regardless
of their manufacturer. And if fluid transportation is required, the
system can also run on coiled tubing, extending its lateral reach
in horizontal, deviated, and extended reach wells. Its pulling force
works to mitigate traditional issues encountered, such as excessive
friction, limited reach and buckling.
Newtechnologydevelopments
Recent developments in tractor technology have led to the
Well Tractor Next Generation (NG), which incorporates a new
electronic/hydraulic design for increased speed and reliability. The
Well Tractor NG currently holds the world record for the longest
cumulative distance tractored on one job, conveying its payload for
423 723 ft offshore Norway. These new improvements have enabled
a shortened solution, the Well Tractor Compact Rig‑up (CR), which
can be configured to less than 10 ft. This new tool has been used in
several recent North Sea operations.
Casestudy1
A highly deviated, water injector well offshore Norway had a
leak in the tubing above the downhole safety valve (DHSV) that
required remediation. Due to a limited rig up height of only 42 ft,
standard equipment would be extremely difficult to use safely.
The Well Tractor CR was subsequently chosen for this problematic
situation.
On the first run, the Well Tractor CR conveyed a 40 finger
caliper into the well where it logged from 13 255 ft. Following the
successful logging operations, the client decided to set a plug just
above 13 255 ft, and the tool was used again. The CR even passed
power through to a third party setting tool that set the plug.
During these operations, the Well Tractor CR achieved
tractoring speeds of nearly 7000 ft/hr, showcasing the power of the
new NG technology. The optimised speed and reduced tool length
saved the client 3 ‑ 4 hours compared to other e‑line conveyance
solutions.
Casestudy2
In another well offshore Norway an operator needed to pull
a deep‑set plug in a well with >90˚ deviation. Conventional
solutions required leaving well safety valves open in order to
accommodate the length of the toolstring, an option the operator
would not consider. The challenge came from the combination
of the limited rig‑up height and the highly deviated well, which
would require high pull forces. The available rig‑up/rig‑down
Figure 1.
The 4
½
in. Well Tractor tools get checkedat thewellsite.
Figure 2.
The anchor sections of a slim, 2⅛ in. Well Stroker.
