PEH Volume I Chapter 9: Asphaltenes and Waxes

The 18 chapters in the Petroleum Engineering Handbook (PEH) Volume I are as follows.
This post will review Chapter 9:

C1-3: Math
C4: Fluid Sampling
C5: Gas Properties
C6: Oil Correlations
C7: Thermo/Phase
C8: Phase Diagrams
C9: Asphaltene/Wax
C10: Produced Water
C11: Phase Behavior
C12: Emulsions
C13: Rock Properties
C14: Permeability
C15: Relative Permeability
C16: Economics
C17: International Law
C18: 21st Century Law

C9 Review:

PNA: Paraffinic, Naphthenic, Aromatic (includes resins & asphaltenes) fractions. (I-400)
SARA: Saturates, Aromatics, Resins, and Asphaltenes. SARA Analysis: weight fraction method.

Asphaltenes and Waxes (I-397-400)
Deposited solids: asphaltenes, waxes, or a mixture (with resins, crude oil, fines, scale, water) Characteristics: Light C6 fraction (with N2, CO2, H2S), heavy end C6

Asphaltenes 
Asphaltenes precipitation in reservoir: by decreasing pressure or mixing oil with injected solvent. Asphaltenes precipitation near wellbore: by drilling, completion, acid, fracs, etc.
Heavier crudes have less asphaltenes-precipitation problems than lighter crudes.
Primary production has maximum asphaltenes around the saturation pressure.
Asphaltene precipitation/deposition envelope (APE) has dependence on both P & T.
APE: the region which asphaltenes precipitation occurs.

Waxes 
Wax precipitation envelope vertical P/T curve; strong dependence on T but weak on pressure.
Wax crystals tend to fluid disperse (deposit on a surface more likely among fines, asphaltenes, clays). Temperature drop is most common cause of wax deposition; oil/gas expansion (sandface, orifices).

PEH Volume I Chapter 8: Phase Diagrams

Phase Diagrams:
     Critical Temperature: max T two phases exist (higher T only vapor).
     Critical Pressure: max P two phases exist (higher P only liquid).

Surfactant/Polymer Flood: oil/water soluble mix reduces interfacial tension oil/H2O interface.
Gas-Injection: miscible displacement eliminates oil/displacing phase interface capillary forces.

Phase Rule: component number determines max number of phases coexisting at fixed T, psi.

Phase Diagrams: Plait Point: where bi nodal curve liquid & vapor portions meet and compositions are identical.. 
          Binary: Vapor/liquid; fixed T; pressure-composition (p-x-y) 2 components (I-373-375). 
          Ternary: 3 components; each component equilateral triangle. (I-376-381). 
               …composition expressed in volume, mass, or mole fraction; 100% on each corner. 
               …line parallel to a side is a constant fraction of the opposite corner component.
               …perpendicular lines from any composition point to each side (LT) sums to any side.
               …two phase regions fall on the triangle sides. 
          Quaternary: 4 components; tetrahedral diagram, faces are ternary phase diagrams.

Reservoir Fluid Systems: See Guidebook 13 RES 10

Much of this material is being added to the Guidebook; in the meantime, feel free to pencil it in.

Note that ternary diagrams are a rich target for questions; read section 8.5 carefully. Understand how the ternary diagram is used, and underline the key passages relating my notes above. Often, what makes sense physically isn't so clear when put into words, and vice-versa.

Be warned: I've observed each person will have their own weak areas on this subject; your needed focus may be different than mine or others. So skim all the material and underline key passages (in pencil: in a year the subject may seem bloody obvious so leave the option to erase half of it later to keep your focus on weak areas).

PEH Volume I Chapter 5: Gas Properties

The next chapter in Volume I of the Petroleum Engineering Handbook worth reviewing is Chapter 5: Gas Properties.

Most of what you will need regarding gas properties is in the Petroleum Engineering Guidebook on page 9 PVT 2. Review this page closely, especially the notes and equations. Know how to use the chart.

Below is some additional material. Again, if unfamiliar with anything (especially terminology) read those sections in detail until it makes sense. Otherwise, the outline should suffice.

_______________________________________________ 
Gas Properties:
     CRITICAL: gas can't be liquid
     IDEAL: gas particle volume negligible compared to total gas volume
     PSEUDO: gas mixture
     PSEUDOPOTENTIAL: integral of pressure divided by z factor & viscosity (more accurate)
     REAL: gas particle volume considered; z = real/ideal volume; pV = znRT

Gas Viscosity:
     I-237-240    
     Estimate by chart, Carr et al

Vapor Pressure or Normal Boiling Point:
     I-241-252
     Pressure when vapor & liquid in equilibrium
     Use for pure substance only
     Estimate using: 
          Clausius-Clapevon equation (ideal gas only, accurate <~0.2 psi)
          Cox Chart 
          Calingeart & David or Antoine equation (generally <2% error) 
          Lee-Kesler equation (most accurate)

Petroleum Engineering Handbook: Volume I

The 18 chapters in the Petroleum Engineering Handbook (PEH) Volume I are as follows:

C1-3: Math
C4: Fluid Sampling
C5: Gas Properties
C6: Oil Correlations
C7: Thermo/Phase
C8: Phase Diagrams
C9: Asphaltene/Wax
C10: Produced Water
C11: Phase Behavior
C12: Emulsions
C13: Rock Properties
C14: Permeability
C15: Relative Permeability
C16: Economics
C17: International Law
C18: 21st Century Law

The first chapter in Volume I that is worth reviewing is C4: Fluid Sampling.
Below is an outline. If any of the material is unfamiliar (especially terminology) read those sections in detail until it makes sense. Otherwise, the outline should suffice.

I would especially note the section on "gas sampling for reservoir oil remix"; understand how to use the chart.

Note the list below seems pretty short and simple at first glance, but it's really not. It literally took hours to cull the wheat from the chaff to make this reference. Be aware: 90% of this chapter lacks utility for the average engineer but it's hard to sort it out at a glance.

_______________________________________________ 
Fluid Sampling: RP44

BS&W: Basic Sediment & Water

DST: Drill Stem Test; note samples often unconditioned (early flow)

GOR: Gas Oil Ratio; often largest sample error

P&T: Pressure & Temperature

RFT: Repeat Formation Tester; several depths gradient; note filtrate contamination.

SI: Shut In

WELL CONDITIONING: Flow until stable (WHP/mud filtrate/workover fluids/reaction products).

WHP: Well Head Pressure

Samples:

·           Preserve P&T state during handling/storage.

·           Multiple before excessive drawdown.

·           Asphaltenes: single-phase (monophasic) sampler keeps at reservoir psi.

·           Water: aquifers vary laterally & by depth; RP 45: pH, T, alkalinity, O2, CO2, H2S, iron, turbidity.

·           Waxes: use heated chamber samplers.

·           Separator sample method: 1) drop flow rate by steps, 2) take sample when GOR/flow stabilizes.

·           Separator gas sample volume for reservoir oil remix; need separator GOR & PSI: FIG 4.4 (I-190).

·           Wellhead/Flowline: single phase only (e.g. dry gas, very-low GOR, or high-P high-T condition).

·           Split-stream sample (isokinetic): two-phase; side stream equal velocity (e.g. gas condensate).

·           Choke may change GOR: due to 1) two-phase flow effect, 2) phase changes, 3) gas condensate.

·           Downhole capture method: 1) SI for pressure, 2) flow low to clean near wellbore, 3) SI, 4) sample.

·           Downhole capture tools: by timer, mechanical clock, or electrical signal.

 

Petroleum Engineering Handbook: Overview

Petroleum engineers should be familiar with the Petroleum Engineering Handbook (PEH). See the Amazon link, lower left under "Useful Links" for further information. Many engineers have been slow to embrace the PEH for several understandable reasons:

First: seven volumes?! Clunky.
Second: each chapter is written by a different author so the quality is uneven. It lacks the unity of its single-volume predecessor by Bradley (see my Amazon review linked in the upper-right corner of this blog).

Regardless of one's opinion of the PEH, every PE should purchase and become familiar with it. Bradley is simply too dated, and there is some pretty good stuff in the PEH. After you get used to it, it's really not that bad. However, I do have suggestions to make it more manageable:

1) Tab each chapter in each volume, clearly labeled (see picture below).
2) Tape a chapter TOC (with page numbers) to both the cover and spine for quick reference.
3) Use pencil to mark passages. Forgo pens or highlighters. As you learn more and gain more experience a lot of the original marks will be obvious and make it hard to discern what's important. You really need to be able to erase and remark as you go.

I try to include relevant quotes from the PEH in the Guidebook. This process is ongoing.

Note the PEH is very long and detailed, so a good percentage of it is simply beyond the scope of the PE exam and most engineering work. Reading it cover-to-cover is not a wise investment of precious time for the typical engineer. So be selective when reading it. Make no mistake, it's a deep dive.

On this blog I'll include an ongoing outline of what I think are "relevant" PEH chapters (starting this week). These posts will be an excellent review for people taking the PE Exam. Everything I include I think is worth knowing and being prepared for.

2017 PE Exam Comments

2017 is history. Leave any comments (and suggestions for blog or GB improvements) in the comments below. I would enjoy hearing from anyone and everyone.

Please remember the blog rule: prior PE Exam questions, in whole or in part, will NOT be discussed on this blog. General topics, such as resources, testing techniques, or general problems only!

Test Taking Strategy - 2017

Note: I will not talk about specific problems from the exam.
Note: this is a re-post from 2016 with updates for 2017.

First: review the Petroleum Engineering Guidebook in detail and SPE Textbook Series #1, #2, #12, and #4 as time allows. Tab (by letter) a good Petroleum Dictionary. Have the Halliburton Red Book (or equivalent) and Well Control or something similar (for the pictures). Consider investing in the 7 volume Petroleum Engineering Handbook; you really should own it anyway and it helps a lot of folk on the exam. Regardless, know whatever resources you choose very well; never waste time searching through books on a hope during a timed exam.

Second: Take the Petroleum PE Problems 2016: 1-40 or the 2005 SPE Sample Exam 1-40. It's critical to take it under actual test conditions. Lock yourself in a room for four hours with your books, calculator, mechanical pencil, and whatever you will eat and drink. If you lack four uninterrupted hours, do 10 problems in 1 hour for the same effect.

Third: Take, practice, and completely understand every problem on the 2005 SPE Sample Exam 1-80. This is your calculation problem study time. Do every problem as many times as needed until each one takes less than 6 minutes each (on average).

Fourth: Review whatever reservoir textbook you are familiar with. If you have time, you might want to do and completely understand every problem on the 2014 SPE Practice Exam (this isn't like the actual exam, it's mostly easy and fast, but worth a look if you have extra time). Study any weak areas.

Fifth: Take the 2016 Petroleum PE Problems 2016: 41-80. If you don't have it, use the 2005 Practice Exam 41-80. This is your final check. If you can get 70% under exam conditions, you will probably pass the real thing. If you can get 60%, it's worth a shot. Use this test to hone your resources and test-taking skills under time constraints.

Sixth: Sometime in the month before the exam, take the Petroleum PE Problems 2017: 1-80. Take it as if it's real, including resources, food, and restroom breaks. Regroup and study as needed. If you have the opportunity to take review courses (Bing is highly recommended) do so. The lectures are invaluable, especially for engineers without a petroleum degree.


Regarding studying: I didn't find practicing calculation problems to help much past a certain point. If you can do every problem on the 2005 exam within time constraints (average 6 minutes per problem), you should be good to go on calculations.

Regarding the futility of studying calculation problems to prepare for the PE Exam? Read David Vaucher who after taking the 2014 exam said, "I think I did well. I’m confident because I spent ample time preparing..." and "...I am certain that I got all the calculation questions right...". But to his chagrin he then learned he did not pass. Think about that. He believes he didn't miss a single calculation problem...yet did not pass! This demonstrates the danger of relying on calculation problems.

So how should one prepare? Focus on high-quality (but limited) resources, achieve real understanding, and hone your test-taking skills. This was how I generated my study notes (now Guidebook) during the years I waited to take the exam. My notes summarized the main points from SPE textbooks. And little else. If there was something on the exam not in my notes (rare!) I merely skipped it, confident that the question was esoteric and thus a time sink to be avoided. A willingness to "let it go" is far more important than the natural (and normally healthy) urge to chase down the correct answer on every problem and thus run out of time.

You have probably heard the joke that to avoid being eaten by a charging bear you don't have to outrun the bear, just the other guy? Well you don't need to get every answer right on this exam. You just need more answers correct than about half the other guys.

2017 Test Study Plan

If you passed the 2016 Exam, congratulations. I'm hearing from a lot of you who did [edit: rumor has it the cut-off score is 43; if you agree or know different, please leave a comment below].

If you didn't pass, don't let it get to you. It's no big deal. What doesn't kill you only makes you stronger. Remember, anyone who can pass the FE exam has already shown they have the brains to pass the PE if they 1) study enough, 2) keep a positive mental attitude, and 3) do enough practice exams or similar problems.

My study suggestions for 2017:

1) Read the 2016 exam comment thread (link to left) and every blog post regarding testing methods and resources.

2) Select and acquire your chosen resources. Start reading them today.

3) Read the Guidebook carefully, every word, until you know it extremely well. Learn any concept in it you don't completely understand. Tab chapters; practice using the TOC. Ensure you have the second printing (I'll update your old one for free).

4) Get to where you can solve every 2004 Sample Exam question in under 6 minutes. The 2004 is not like the modern PE exam but it's a great tool for subject mastery. If you have questions about any particular problem, I have similar example problems linked on the right-side of this blog.

5) Months before your 2017 test date (I prefer 6 months) take the 2016 AM Practice Exam (under test conditions). From this experience, decide on your "testing strategy". My preference is 5 problems (done in order) each half-hour, never to return. However, many people prefer to do the easy ones first, or even do them by subject. Choose your method now, in order to practice it on future practice exams. You will test like you practice.

6) Study weak areas. Continue to do practice exams or realistic problems. Make sure that you fully understand every problem you see on a practice exam, even if you get it correct. On the real exam, you will be under stress and may not be so lucky.

If you don't intend to use the Guidebook or Practice Exams, that's no problem, just make sure you know your primary resources well. If you can afford it, take Bing's class (see link to the lower left). You can also learn problems from any SPE Textbook Series as practice problems, or the SPE Certification Exam. There are lots of free options out there.

I don't recommend bringing sample exam problems to the real exam. You won't have the time to be looking around for similar problems when testing. To highlight a particular problem, make notes in your primary resource.

Q & A

I often get questions about what is the best "method" to take the PE exam.

Here's my experience. Keep in mind everyone is different and YMMV.

1) I brought all my books (3 totes on small dolly) and faced them up (like a laying-down bookshelf) in an organized way (how I did my practice tests). Those totes sat on the floor to my left and right. I had the entire 7 HS, 12 TS, a dozen spiral-bound API docs, Redbook, Dictionary, Well Control, Bradley, Bing, Mian, etc.,etc. This setup was an absolute waste of time. But it made me feel better!

2) I kept the GB, calculator, pencil, paper, test book on my desk. The desk was big and roomy. The wall clock was fine, but we didn't start on time on either half-test, which threw me off on how I watched my timing.

3) Wore one digital watch with no sound (a guy got kicked out of our test for his watch beeping a single beep just twice!).

4) Wife brought a light lunch; I ate in the testing building. I brought no food into the exam itself and drank a limited amount of water (to avoid the restroom). My intent was to take NoDoz or Jet Alert for a caffeine buzz, but forgot them. And I was tired too: I packed late plus goofed off the night before. Yep, I was that stupid...

5) Earplugs were provided (use them!), pencil, paper. I never used my straight edge. No time.


What worked best for me regarding test strategy?

A) I divided each half-exam's 40 problems into 8 "mini tests"; 5 problems each 30 minutes. I did them in order. With leftover time, I checked and rechecked those five problems until my 30 minutes was up. If I couldn't finish one or more within the 30 minutes, I moved on, never to return.* I believe this was the most important thing I did when taking the exam because if forced me into rigorous time management.

B) I resisted opening any book (besides the GB, dictionary, or Redbook) until I was done and checking my work. This prevented me from "flipping pages" in vain on any particular problem. I think this was the second most important thing I did.

C) The dictionary was the unexpected killer resource (thanks Bing!). I used it at least 3 times to help get to an answer. I had mine tabbed by letter. It's a must have. Tab it and get used to using it on practice exams.

D) I used the HS, TS, and Well Control (for the pictures) several times to check answers. They never helped me actually get answers, just confirm what I already suspected, or had in my notes (GB). But I did waste at least 15-20 minutes looking around in them.

E) *I ignored 2 esoteric or long questions (each half exam) until the end (this saved 15 minutes which I used to revisit them at the end of the exam). If I wasn't familiar with a problem, I just worked it fast and moved on, expecting to miss it. But that was rare. I found the test subject matter fair and as expected. I didn't have a desire to add anything to my notes (GB) at the end of the exam.

F) Each hour, I forced myself to stop, put my pencil down. close my eyes, and breath deeply for 15 whole seconds. Best move ever. It's hard to give up that minute, but it made me more productive.

G) I always reviewed/checked my work on all five problems at the end of each 30 minute mini-test. I felt good doing most problems, yet caught at least 3 mistakes each half-exam! Tricks. And these were problems I was confident I knew how to do; I was merely doing a routine check. This left me jittery and unsure of myself. How many more did I miss? So I left the exam wondering if I had passed, but reflecting I realized I probably did very well because of my paranoia.


What surprised me?

I) My many books didn't help me at all (like many others think they do). If anything, they hurt me by using valuable time (except the dictionary; that was an awesome tool; HT Bing!).

2) How much my notes (now the GB) helped to "center" me and remind me what I already knew. At the start of any problem, I always flipped to the relevant GB chapter for a quick scan for a refresher. I can't explain how hard it was to switch from drilling to rod pumps to reservoir to API specs to some word problem about geology to...you get the idea. I simply can't adjust like that effectively without a quick overview of the subject to focus my mind.

3) How difficult it was to manage time, stay focused, and remain unemotional for 8 hours. It was the hardest and longest exam I've ever taken. It's not a sprint; it's a marathon and the winners separate themselves from the pack in the second half, long after the excitement is gone. It's all about pace, stamina, and time management.

4) How much the lectures from Bing's class helped. Especially the review of TS1 and TS2. I missed taking the exam in 2014, the year I took Bing's class, yet I still remembered quite a bit from the lectures. Lots of good stuff in those lectures if you are lucky enough to be able to take it. See the link to the lower left to find out more about Bing and when his classes are available.

Question: Ton Mile (TM) Calculations

Q1: In the Guidebook, page 1 RIG 5 says: "RTTM equation assumes DP to bit, so wdp is subtracted from wbha." What are the mechanics behind this? Is there anything online to help understand this?

This formula is found many places and formats; I think this version is from Lapeyrouse's Formulas and Calculations for Drilling, Production, and Workovers. It's a good field book. And while this sort of problem may be too "real world" for a typical PE Exam question, I include it because something like it could easily show up.

The equation used assumes the DP goes all the way to the bit, then subtracts the DP over the BHA length later. There are other ways to skin this cat but I prefer this method because I find it faster. And speed is everything on the exam.

Q2: On 1 RIG 5, why is tripping RTTM multiplied by 1, coring by 2, & drilling by 3?

For drilling or "connection" TM, use the TM for actual drilling, plus the TM for picking up, connecting, and starting to drill again. This is 3 lengths, so multiply by 3 over the drilling depth.

For coring, you don't need to pick up again; just add another stick. So you multiply by 2.

This would be a great word problem for the PE Exam, to test one's understanding of how the TM equation actually works. So it's an excellent question. It's very easy for a test writer to nail those who survive by "plug-and-chug" and lack understanding.

Question: Units

I recently received an interesting question:

While reading through the Fundamentals of Drilling Engineering book (great recommendation, by the way---SO much better than the older version!) I noticed the book recommends converting everything to SI, and then when solving go back to field units.  I think your guidebook has most equations with constants to automatically solve in field units, right?  What is your recommendation as far as going back and forth?  As a ChemE used to doing tons of unit conversions, sometimes I am blown away by the constants that magically turn the answer into the right units.   Interested to know your thoughts.

First, this reader is correct on the quality of the FDE book. It's clearly a big-time reference used for the PE Exam. If I could study only one book, it would be this one. It's a bit large to use for an exam reference (the Guidebook though has most of what you need from the FDE) but it's excellent to study from. Every engineer should read through it and know what's in it well.

To answer the question: this exam is a speed demon. Excess unit conversions should be ignored in nearly all situations except reservoir, where it makes sense to quickly convert units to whatever is familiar to you.

Sidenote: It's extremely hard (especially for good engineers) to "let go" of the precision and detail that's natural to them at work. Well, this PE Exam is not a "normal" situation. You are going to miss problems that would get you fired in real life due to the rush. Accept it. Get used to it. In fact, a large part of one's study plan should be practicing this "letting go", that is, of getting used to guessing on difficult problems long before they become a time sink. And most importantly, not letting this effect your positive mindset for the rest of the exam. Use timed, realistic practice exams to drive home this mental switch.

Question Thread 2017

Please place your questions in the comment section.

Open Thread - 2016 PE Exam Comments

2016 is history. Leave any comments (and suggestions for blog and GB improvements) in the comments below. I would enjoy hearing from anyone and everyone.

Questions: Practice Exam

Question: Is the Practice Exam available in hardcopy, or just Kindle?

Answer: Kindle only. It's easy to use; just download the free app to your phone or computer. Then scratch paper is all you need.


Question: On your practice exam, did you come up with the problems yourself or are you getting them from other practice exams, or Bing's class?

Answer: My practice exam problems are from my Guidebook. Bluntly, I just made them up. There is nothing copied from anyone else. Sources for the Guidebook (and thus my practice exam) are listed in the Guidebook on each page. At the end of the exam, it shows the exact page of the Guidebook used to create the problem.

My problems are not much like Bing's (mine are mostly word problems, for example). Bing's problems are broken up into parts for studying and learning, while mine are in an exam format.

Sidenote: Bing's class is AWESOME. I took it several times. I think every petroleum engineer should take it, exam or no. However, my Guidebook and practice exams are a very different approach. I do think they work well together though; everyone has a different learning style.

Questions: 2009 & 2011 Exams

I received a good question today: In addition to your 2016 Sample Problems and the 2004 Sample Exam. what do you think of the 2009 AND 2011 SPE/PE study guide questions?

My response: You have limited time, so make the most of it. And that is the 2016 & 2017 Practice Exams, the 2004 Sample Exam, the 2014 Practice Exam, and of  course the Guidebook. First know those like the back of your hand.

Once there, study the recommended resources until you know them like the back of your hand. And that includes the problems (from TS #1, #2, #4, #12).

Only after all that would I study the 2009 & 2011 Exams.

Questions: Certification Exam

I'm currently talking with several people who are taking the 2016 PE Exam, and the same questions keep coming up:

1) What is the test like? Is it theory or problems?
2) Is Bing Wines class helpful?
3) Is the Certification Exam worth taking?
4) What is a good study plan?

The first two questions are answered here.

Regarding the Certification Exam: I've never taken it, and don't know much about it.

However: resource selection and use is key to doing well on the PE Exam. And the Certification Exam doesn't allow you to use your own resources. Therefore, I question it's value for the PE Exam. I would probably focus on one of the exams at a time.

For a good "at home" PE Exam study plan:

a) Read this.
b) Read the entire Guidebook, know it well, and study any weak areas. If you don't want to use it, know SPE Textbook Series #1, #2, #4, #12, and #8 (or your own reservoir book) at a minimum.
c) Take the 2016 Petroleum PE Practice Exam Morning Section (under test conditions, or 10 problems in an hour) to get a taste of the exam's pace. If you don't want to use this practice exam, the 2004 Morning Section will work (link at lower left).
d) Know every problem on the 2004 Sample Exam.
e) Take the 2016 Petroleum PE Practice Exam Afternoon Section (under test conditions, or 10 problems in an hour). If you don't want to use this exam, the 2004 Afternoon Section will work.

If you can get 70% you will likely pass the real thing. Even if you can get 60%, take it anyway, since your odds are fair.

If you have questions, leave me one in the comment box and I'll try to answer it. Good luck!

2015 Pass Rates

Petroleum 2015 (October) exam pass rates are available from NCEES. This is the exam I sat for.

First time test takers had a pass rate of 61%. Repeat test takers had a pass rate of 32%.

Look, this was a very tough exam. The fact that repeat test takers had half the pass rate is a warning. Just because you know what is on the exam doesn't mean you will pass it. One would think that repeat test takers would have at least double the pass rate. But it's exactly the opposite. So either it's merely a measure of raw talent (which is clearly not fully true) or it's about being prepared.

When I took it a five months ago I used my manuscript as my primary resource. It has less than 130 pages which prevents a lot of "looking around".

Passing any difficult, timed open book exam primarily depends on 1) studying from and knowing quality resources, 2) proper test-taking techniques, and 3) harshly limiting resource referencing during the exam. Time is everything. If you flip through books indiscriminately your chance of passing drops rapidly. Know exactly where the answer is, or let it go.

If you are planning to take the exam in October of 2016, you should already have all of your resources by now and be studying them. You should have taken a good practice exam (say the AM portion of the 2004 Practice exam, or equivalent) under actual test conditions. Practice exams are the best study guide you have to introduce you to what you need to study. Some people recommend you to wait until close to exam time to take a practice exam, but I strongly disagree. Take them early, take them often. It will clue you in on how and what to study. You should also schedule at least a week of concentrated study time as you approach the exam itself.

Now is the time.  Don't delay. Get your resources. Take the practice exam. The test will be here before you know it.

Test Taking Strategy

Note: I will not talk about specific problems from the exam.
Update: This post was updated with the completion of the Petroleum PE Sample Exam 2016.
Update: This post was updated using suggestions from Guidebook readers after the 2016 exam.

First: review the Petroleum Engineering Guidebook in detail and SPE Textbook Series #1, #2, #12, and #4 as time allows. Tab by letter a good Petroleum Dictionary. Have the Halliburton Red Book (or equivalent) and Well Control (for the pictures). Know whatever resources you choose very well; never waste time searching through books during an exam.

Second: Take the 2016 Petroleum PE Practice Exam Morning Section or the 2004 Sample Exam Morning Section. It's critical to take them under actual test conditions. Lock yourself in a room for four hours with your books, calculator, mechanical pencil, and whatever you will eat and drink. If you lack four uninterrupted hours, do 10 problems in 1 hour for the same effect.

Third: Take, practice, and completely understand every problem on the 2004 SPE Sample Exam. This is your calculation problem study time. Do every problem as many times as needed until each one takes less than 5 minutes each (on average).

Fourth: Do and completely understand every problem on the 2014 SPE Practice Exam. This isn't like the actual exam, it's easy and fast, but know all the questions. Study any weak areas.

Fifth: Take the 2016 Petroleum PE Practice Exam Afternoon Section. If you don't have it, use the 2004 Practice Exam Afternoon Section instead. This is your final check. If you can get 70% under exam conditions, you will probably pass the real thing. If you can get 60%, it's worth a shot. Use this test to hone your resources and practice operating under the time constraints.

Sixth: Sometime in the month before the exam, take the 2017 Petroleum PE Practice Exam, Morning and Afternoon. Take it as if it's real, including resources, food, and restroom breaks.


Regarding studying: I didn't find practicing calculation problems to help much past a certain point. If you can do every problem on the 2004 exam within time constraints (average 6 minutes per problem), you should be good to go on calculations.

For an interesting discussion of the futility of using calculation problems to prepare for the PE Exam, read David Vaucher, who, after taking the 2014 exam, said, "I think I did well. I’m confident because I spent ample time preparing..." and "...I am certain that I got all the calculation questions right...". But to his chagrin he then discovered that he did not pass. Think about that. He believes he didn't miss a single calculation problem yet did not pass! This demonstrates the danger of focusing on calculation problems.

So how should one prepare? Focus on high-quality (but limited) resources, real understanding, and test-taking skills. This was how I generated my study notes (now Guidebook) during the years I was waiting to take the exam. My notes summarized the main points from SPE textbooks. And little else. If there was something on the exam not in my notes (rare!) I merely skipped it, confident that the question was esoteric and thus a time sink to be avoided. A willingness to "let it go" is far more important than the natural (and normally healthy) urge to chase down the correct answer on every problem and thus run out of time. 

You have probably heard the joke that to avoid being eaten by a charging bear you don't have to outrun it, you just need to outrun the other guy? Well you don't need to get every answer right on this exam. You just need more answers correct than about half the other guys.

Resources

Unlike every other engineering discipline (Mechanical, Civil, Electrical, Chemical) Petroleum Engineering lacks a good reference manual for the PE Exam. The SPE official resources are:

Society of Petroleum Engineers Textbook Series

Vol. 1, Well Testing, Lee                                                                                                                                                                          

Vol. 2, Applied Drilling Engineering, A. T. Bourgoyne Jr., et al. 

Vol. 3, Waterflooding, G. P. Willhite, et al.

Vol. 4, Theory, Measurement and Interpretation of Well Logs, Z. Bassioni

Vol. 5, Gas Reservoir Engineering, J. Lee, et al.

Vol. 6, Enhanced Oil Recovery, D. W. Green, et al.

Vol. 7, Basic Applied Reservoir Stimulation, T. Ertekin, et al.

Vol. 8, Fundamental Principles of Reservoir Engineering, B. F. Towler

Vol. 9, Pressure Transient Testing, J. Lee, et al.

Vol. 10, Advanced Well Control, D. Watson, et al.

Vol. 11, Streamline Simulation: Theory and Practice, A. Satta-Gupta, et al.

Vol. 12, Fundamentals of Drilling Engineering, R. F. Mitchel, et al.

  

Petroleum Engineering Handbook Series Editor-in-Chief: Larry W. Lake  

Volume I: General Engineering  
Volume II: Drilling Engineering  

Volume III: Facilities and Construction Engineering  
Volume IV: Production Operations Engineering

Volume V: Reservoir Engineering and Petrophysics  
Volume VI: Emerging and Peripheral Technologies

I own all of these books (plus about fifty more petroleum engineering books). Most are not very useful on a timed, open-book exam; no time to flip pages! Remember, ten problems an hour equals only six minutes for each problem. Often it takes several minutes to read/understand a problem. If you waste time looking in hope, you will fail. As I've said before about this exam: if you think, you're dead.

There are only three possible references one could use on the Petroleum PE as a "primary" text. They are below (with links).

1. Petroleum Engineering Handbook (SPE, Bradley)

2. Petroleum Engineering Handbook for the Practicing Engineer (Mian)

3. Winrock PE Review Course (Wines)

I've owned these texts for years. Each is crazy expensive. But I used none of them during the exam. Note you cannot buy the Winrock text; but must take a week-long course to get the text (this course and manual are excellent for education in petroleum engineering and I strongly recommend it., even if not taking the exam).

I know a lot about these three books. Each is tabbed, indexed, highlighted. They were some of my primary texts studied. But I never even opened one during test time. Look, all three are great for learning tools and I strongly recommend each to study from. But for actual use during a 6 minute per problem exam? No way. Were I to take it again, I wouldn't bother to bring them.

So what resources did I use?

1) My own manuscript (or your own notes). This was a concise 130 page summary of about 30 texts. It sat on my desk, spiral bound, always open.

2) SPE Textbook Series Volumes 1, 2, 4, 12.
3) Dictionary of Petroleum Exploration, Drilling & Production.

4) SPE Handbook Series Volumes 3, 6.
5) Update: I forgot to mention Well Control for Completion and Workover (and of course the HES Redbook).

I felt good leaving the exam after the first half. I felt less confident during the second half, but upon reflection understood this was weariness (goofing off the night before and forgetting my NoDoz). 

I made a conscious point to not scan any of my (numerous) resources until the very end of each exam section. Precious time is better spent working, especially checking your work. You either know it, know exactly where to find it (and I mean exactly), or let it go.

Calculator

This is the easiest post to write. You are limited as to which calculators you may bring to the exam.

The best of your (very limited) selection is the TI-36X Pro. Why?

1. 4 Line Visible Stack
2. Reliable (I have 2 and both are working fine years later)
3. Solar Power Backup
4. Inexpensive
5. Nice Button Position/Response
6. Linear Interpolation*

The only reason to chose the other calculator options is if you are already know it well and like it. Regardless, you should give the TI-36X Pro a look. You might be surprised. I'm an HP guy and found the Pro pretty easy to pick up and use with speed from day one.

Bring two of these calculators to the exam (one for backup). It is >$20, so why not? The exam costs $350; why put this money at risk with a battery or mechanical failure? Leave the covers at home; some proctors will not allow them in the room.

*I don't recommend interpolation on this type of exam to save time. I estimate. But if you feel the need, the Pro's interpolation function takes about the same time as by hand (I've timed it). I personally never interpolated, just estimated, and it worked great. When you do practice problems, try estimating, then interpolate to check; you will find it almost never pays to waste time interpolating. Remember, you only have 4 answer selections. Time is your enemy on this exam, not precision. I think I found 1/100 practice problems where guessing got me the wrong final answer. Invest your time elsewhere.

But if you must interpolate, use the Pro's interpolation function because it requires no real "thinking" and is a nice rest from that. Regardless, make sure you practice using whatever method you intend on the exam. Interpolating on the Pro is a tad confusing at first, but easy once you know how:

Example: Given 200, 250, 300 interpolate between 1, 2:
(data)
type in:
----------
200     1
300     2
----------
(2nd) (data)
Scroll 2 down (2_Var Stats)
Scroll 3 down (calc)

Scroll 16 down (y')
Type number to interpolate to, here 250
(enter) gives 1.5

One last calculator trick to use on the exam: get used to using roots as exponents. It's a lot faster to enter y^0.5 for a square root, y^0.3 for a cube, etc. Remember, you will have to do many large roots, so just learn the process for any root and stick with it. It's the same for negative exponents; they are faster than inverting. Again, it's all about speed, and what you practice will be what you do under pressure. You shouldn't think on this exam. You've either done it a million times and crank it out, or you should skip it and invest your time elsewhere. It's funny to say about this type of exam, but if you think, you're dead.