Casing Drillout; Downlinking; Downlinking Basics - Extreme Networks PowerDrive Orbit Quick Operation Manual

PowerDrive Orbit & X6

3.3 Casing Drillout

When drilling out the shoe, keep in mind that Cement Plugs, Float Collar, Cement and Shoe Track are
very different materials compared to the formation intended to drill. The bit is not designed to drill this
material, especially when drilling in a soft rock environment where bits with low blade count and big
cutters (aggressive design) are used.
The real-time shock and vibration levels should be actively monitored, and steps taken to mitigate shock
and vibration levels. The stick slip measurements use the tool's magnetometers to detect collar rotation,
so the measurement will be unreliable inside the casing. Stick slip can still be detected on surface from
erratic and cyclic torque and RPM readings
The following guidelines for drilling out of the casing shoe and rathole should be followed:
1. Inclination hold mode or HIA mode must not be used while drilling out the casing shoe.
2. During the drilling of both the shoe track and the shoe, the flow rate should be reduced to
approximately 75% of planned drilling flow (yet above the minimum drilling flow rate of the Control
Unit). This reduces the pressure drop across the Bias Unit seals and limits the degree of contact
between the pads and the casing.
3. Rotary speed should be limited to approximately 60 rpm while inside the casing string to minimize
shock and vibration.
4. Start drilling Float equipment with medium RPM and low weight. Watch shock and vibrations and
adjust parameters accordingly. Slow down whenever a material change is expected. Watch
shakers for pieces coming up. Always use float equipment with a locking feature to assist in drill
out.
5. Increase the rotary speed only when the uppermost stabilizer is out of the shoe and into new
formation.
6. When drilling through the casing shoe and the larger diameter rathole, the BHA is unconstrained
and is susceptible to extremely high shocks. This can lead to catastrophic hardware failures.
Monitor shock and vibrations closely as soon as you start drilling. Manage this problem by
monitoring shocks and keeping the RPM as low as practicable until all the stabilizers have entered
the newly-drilled gauged hole.

3.4 Downlinking

Downlinking Basics

3.4.1
Downlinking is the method by which a directional driller communicates with the PowerDrive tool to
change steering settings. PowerDrive X6 and Orbit can accept both Flow and Rotary downlinks. Flow
downlinks are sent by varying the flow rate between high and low levels, typically 20% variance. Rotary
downlinks are sent by varying the surface RPM between high and low levels. The variance for Rotary
downlinks must be at least 40 RPM.
Warning: When sending Rotary downlinks to X6, the downlink timing sheet will need to be "tricked" by
selecting Orbit. This is because X6 outside of the U.S. cannot accept rotary downlinks.
There are 3 different bit periods available when sending downlinks. 18 second, 36 second, and 60
second. Just as a pulse MWD system might require slower and larger pulses as depth and mud weight
increase, PowerDrive may require larger bit periods and greater variations in flow as depth and mud
weight increase. The typical downlinking times are as follows. They may be longer if downlinking
immediately after a connection:
Extreme Equipment Rentals
Bit Period Downlink Time
18 Second → 4:57 minutes
36 Second → 9:54 minutes
60 Second → 16:30 minutes
Quick Operations Guide - rev1.4
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