D
rilling for oil and gas requires mud to be pumped through the bottom hole assembly (BHA) – in
order to lubricate, cool and bring cuttings back up surface.
A bypass tool, often referred to as a circulation sub, can redirect the flow of the drilling mud,
bypassing the BHA. In more sophisticated tools, there will be multi-cycle functionality; allowing the
bypass and pumping sequence to be completed multiple times, each time redirecting flow back to the
bit between each cycle. This can be useful for boosting flow rates to clean the hole or to avoid putting
formation treatments through the BHA.
Anewsystem
The DAV MX™ CircSub is an easy to use multi-cycle circulating sub (CircSub), which is designed to deliver
a faster and more reliable bypass than traditional ball activated tools. Using MX (mechanical extrusion)
Smart Darts™ for activation, the tool is designed to offer rapid and reliable deployment on multiple
circulation applications – including loss curing, hole cleaning, displacement, self-filling and dry tripping.
The simplistic design brings reliability and the single-use darts add ease of use and flexibility. What is
particularly valuable however is the regular access to new applications using the same tried and
tested tool.
With a 99% opening and closing reliability – the tool is in use with over 60 operators,
offers 100% BHA bypass functionality and has been activated at a depth of nearly 30 000 ft.
The tool is now approaching the 1000 run mark, and was the number one choice
for many US and European drilling teams in 2015. Development has continued
THE
BENEFITS
OF BYPASS TOOLS
MIKE CHURCHILL, CHURCHILL DRILLING TOOLS, UK, EXAMINES A NEW
MULTI-CYCLE CIRCULATING SUB DESIGNED TO DELIVER FASTER AND MORE
RELIABLE BYPASS THAN TRADITIONAL BALL ACTIVATED TOOLS.
|
21
