Professional Engineering Exam - Petroleum Engineering Questions And
Verified Answers
Causes for INCREASE in Pore Pressure - Answer 1). Undercompaction by rapid burial of
lowperm sediments
2). lateral compression
3). Water release from clay minerals from heating & compression
4). Expansion of fluids from heating
5). Fluid density contrasts
6). Buoyancy effects
7). Fluid injection
Causes for DECREASE in Pore Pressure - Answer 1). Fluid shrinkage
2). Unloading
3). Rock dilation
4). Reservoir depletion
Which of the following faulting regimes is the ONLY one in which the vertical stress is
the GREATEST principle stress? - Answer Normal
What is the ONLY way to determine pore pressure correctly? - Answer Direct
Measurement
Why is it problematic measuring the pore pressure of a shale? - Answer very low
permeabilities and small pore volumes
What are the various strength criterions, and what are the characteristics? - Solution
Mohr-Coulomb - 2D w/2 criterions (Cohesion So & UCS); stress difference at failure is
,linear to confining stress
Hoek and Brown (HB): 2D, 3 criterions
Tesca: simple version of Mohr-Coulomb
Modified Lade: 3D but requires only 2 empirical constants equal to UCS; preferred for
wellbore stability
What are some techniques that can be utilized to determine the strength properties of
rock? - Answer Single-Sample Testing: triaxial tests are difficult & time-consuming,
require similar/identical cores
Scratch Testing: no special prep; in lab or in on rig; no damage to core
Penetrometer Testing: no special prep; blunt probe
Note: estimating uniaxial compressive strength using rig site measurements is NOT
straightforward
Where are drilling mud samples usually collected? - Answer Suction pit and Possum
Belly
P possum belly A metal container at the head of the shale shaker; its purpose is to slow
the flow of drilling fluid so it does not shoot out of the shale shakers. Generally used
when bentonite or another form of "mud" is being used.
Mud pit connected to the intake of the main rig pumping system; last mud tank in the
surface mud system before mud is pumped into the well
,Where are mud temperatures are usually monitored? Answer Suction pit and Mud
Return Lines
What is the most usual contamination sources of drilling mud? Answer Pipe scale, pipe
dope, and air entering the drill string at connections
Where are gas samples normally taken during drilling operations? -Answer At the "gas
trap" or gas extractor
E
The gas extractor is part of the mud conditioning system
E
Underbalanced drilling is. -Answer Drilling with the bottom hole pressure of the well
purposely below the formation pressures
E
Which one of the following maintains the well under control while underbalanced drilling
operations? -Answer 1). cuttings drilled which increase the fluid hydrostatic pressure
2). friction pressures from circulation
3). choke pressures applied at the surface
FR - § 1 Well Control PROBLEMS Underbalanced Drilling
What is the most common well control problem when ublerbalanced drilling? - Answer
Flow Control
Note: NOT pressure control
What are the benefits of underbalanced drilling? - Answer1). eliminates filter cake
formation
2). eliminates mud invasion into formation and enhances productivity
3). ROP is increased
4). bit life is increased
5). ability to gather reservoir information is enhanced
6). reduces formation damage
, 7). reduces differential sticking
8). decrease lost circulation
What are the disadvantages of underbalanced drilling? - Answer 1). increased costs
2). increased drilling risks
3). increased torque
4). increased drag
5). increased erosion
6). decrease MWD compatibility
7). decrease wellbore stability
What is the procedure for a workover during an underbalanced drilling operation? -
Answer 1). set a suspension plug in the production packer tailpipe
2). Lube to kill fluid
3). underbalance well
4). pull packer
What type of behavior is observed while initiating fluid circulation? - Answer Thixotropic
behavior is observed till fluid is sheared
Various Considerations for Weight of Drilling Mud - Answer MW used at surface
ECD & ESD used in hole
Subsea Drilling Operations - Answer When bringing a well with a subsea stack on choke,
casing pressure (annulus pressure) must be allowed to decrease by the amount of the
choke line pressure loss.
Reduced Casing Pressure = shut-in casing pressure minus choke line pressure loss
Where most friction is generated in the mud circulation system? - Answer Most friction
is generated in the drillpipe
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller Easton. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $11.99. You're not tied to anything after your purchase.