about 70 % of the existing reservoirs are impossible to reach with conventional drilling . MPD or managed pressure drilling is the best solution for HPHT and very deep reservoirs .

1. Under supervision of :
Dr / Ahmed Elgebally

2. Presented By:
Muhammed Esmaeil Abd El Baky
Ahmed El Sayed El Sodany
Muhammed Mostafa
Abdullah Ramadan Helmy
Muhammed Ahmed Elsayed El Mahmoudy

3. The undrillable wells are now drillable

4. Agenda
Introduction
Types of managed pressure drilling
Applications of managed pressure
drilling
Economics
References

5. As current reserves deplete , it is necessary to drill to
reservoirs that are deeper and more complex . Some
industry professionals would say that 70 % of the
current hydrocarbon offshore resources are
economically undrillable using conventional drilling
method . Managed pressure drilling is a new
technology that uses tools similar to those of UBD to
better control pressure variations while drilling a well .
The aim of MPD is to improve the drillability of well by
alleviating drilling issues that can arise .

6. MPD can improve economics for any well being
drilled by reducing a rig’s nonproductive time
NPT .
NPT is the time that a rig is not drilling . Many of
the drilling problems in any well can be reduced
by using MPD

7. Pressure gradient windows

8. As a well is drilled , drilling fluid is circulated in
the hole to obtain a specific bottomhole
pressure . The density of the fluid is determined
by the formation and pore pressure gradients
and the wellbore stability . The previous figure
shows a pressure gradient profile of a well . This
profile shows the change in pressure as the
depth increases.

9. Pressure window is the area between the pore
pressure and fracture pressure .
The goal when drilling a well is to keep the
pressure inside this pressure window .

10. In a static well , the pressure is determined by
the hydrostatic pressure of the mud . In
conventional drilling , the only way to adjust the
pressure during static conditions is to vary mud
weight in the well .

11. Conventional circulation

12. Static wells
The pressure in the well is less than the pore pressure
and the well takes a kick ; that is ; hydrocarbon flow
into the well . After a connection , the pumps restart ,
the BHP increases and the pressure goes above the
fracture pressure resulting in lost circulation or fluid
flow into formation . The goal of managed pressure
drilling is to manage the pressure and remain inside the
pressure window to avoid many drilling problems .

13. How managed pressure drilling works ?
The basic technique in MPD is to be able to
manipulate the BHP and the pressure profiles as
needed . In conventional drilling , the BHP can
be calculated by summing the mud weight
hydrostatic head and the annular friction
pressure AFP , that results from the circulation
of mud while drilling .
ECD is defined as the equivalent circulation
density of the BHP

14. what happens during connection is
Pumps turn off
Fluid stops circulating
Thus eliminating the AFP
Reducing BHP
This leads to …….

15. MPD
uses a closed and pressurizable mud system .
With a closed system the equation for the BHP
can be varied to include Back pressure SBP .
Adjusting backpressure while drilling can quickly
change the BHP . The basic configuration for
MPD is to have a rotating control device RCD
and a choke . The RCD diverts the pressurized
mud returns from the annulus to choke
manifold

16. A seal assembly with the RCD enables the mud
returns system to remain closed and pressurized
. The choke with the pressurized mud return
system allows the driller to apply backpressure
to the wellbore . If the pressure starts to climb
above the fracture pressure of formation , the
driller can open the choke to reduce
backpressure and bring pressure down . If the
driller needs to increase pressure throughout
the well , closing the choke will increase back
pressure

17. NPT
NPT could be reduced by using MPD

18. Types of managed pressure drilling
Constant bottomhole pressure
Pressurized or Mud cap drilling PMCD
Returns flow control
Dual gradient drilling DGD

19. Dual gradient drilling

20. DGD

21. The previous figure show that :
Single gradient wells ; wellbore contains a
single density fluid and single pressure
gradient
Dual gradient well ; wellbore feels
seawater gradient to the sea floor and mud
gradient to bottom

22. Returns flow control

23. PMCD

24. MPD Applications
kick control ( influx control )
Severe drilling fluid loss – fractured or vugular
formation
Differential sticking – stuck pipe - twist off
Depleted reservoir drilling
HPHT drilling
Unknown pore pressure

25. Unstable wellbore
MPD + ERD (extended reach drilling )
Low ROP
Drilled gas
High H2s levels
High ECD
Ballooning / Breathing formation

26. Unexpected Increase in pump speed indicates
for a kick !
Unexpected decrease in pump speed indicates
for fluid loss !
Solution
Early detection limits the size of the kick so it
can be circulated out safely
The riser mud level is decreased reducing
hydrostatic pressure

27. Ballooning / breathing formation
The formation charges up with fluid and
pressure while drilling and releases this fluid
pressure back into the wellbore when pumps
are shut down .
The drilling supervisor thinks the well is flowing
and orders the mud weight increased which
increases BHP which charges the formation even
more so it flows even more in the next
connection

28. MPD solution
If the well is flowing due to influx – the
flow trend will be gradually increasing . But
if the problem is ballooning formation then
the flow trend will be decreasing .
An automated PMD system with highly
accurate flow measurement can clearly
identify what is happening !

29. Economics
With MPD , we could reduce hole costs by about
39 $ per foot drilled
Which means that in wells drilled to 15000 ft ,
that can equate to an average savings of
585000$ per well .

30. References
-Matthew D.Martin, Managed pressure drilling
techniques and tools, 2006, Texas A&M University.
-Charles R. Stone ‘’sometimes neglected hydraulic
parameters of underbalanced and managed pressure
drilling’’,2008 SPE/IADC Managed pressure drilling and
underbalanced operations conference and exhibition.
-E&p Magazine ‘’Managed pressure drilling adds value
‘’September 2004.
-Schlumberger’s oil Field Glossary.