## IWCF Drilling Calculation Part 1 – 3 Review

International Well Control Forum (IWCF) has provided useful learning material, which is IWCF Drilling Calculation Part 1 – 3, to drilling people. We will review all of them and see the content inside. Additionally, these ebooks are available to download from IWCF website. Thanks for their contribution to drilling industry.

## How To Perform Volumetric Well Control Method

This article will demonstrate how to perform volume metric well control. There are a total of 5 steps as listed below;

Step 1 – Calculation

Three calculations must be determined before conducting volumetric well control.

1. Safety Factor (SF) – The Safety Factor (SF) in an increase in bottom hole pressure which we allow to happen naturally when gas influx migrates up with the shut in well. SF is important because it will allow the bottom hole pressure to be over formation pressure so the well is not in underbalance condition while conducting later steps. Typically, SF is around 50 – 200 psi. If the initial shut in casing pressure is very close to maximum allowable surface pressure. Personnel must select small safety factor to prevent fracturing formation.

2. Pressure Increment (PI) – It is pressure used as a working pressure while conducting Volume Metric well control. This pressure will be equal amount of hydrostatic pressure of mud bled during each step.

3. Mud Increment (MI) – It is volume of mud bled off from the annulus to reduce hydrostatic pressure by amount of Pressure Increment. It is very important that the rig must have an accurate measurement to measure small amount of mud bled from annulus. Mud Increment is determined by the following equation:

Where;

Mud Increment is in bbl.

PI is pressure increment in psi.

ACF is annular capacity factor in bbl/ft

MW is mud weight in ppg.

This is a very good book for well control “Wild Well Control’s Technical Data Book” which is a quick reference book of formulas, charts and tables. This is new link updated 2018.

I’ve found that it is very useful because it contains a lot of useful information as formulas, table, technical specification, etc.

These are the table of content from this book.

Acronyms & Abbreviations ………………………………………………………………………. 2
Common Formulas & Equations
Capacities & Volumes for Downhole ……………………………………………………… 4
Capacities & Volumes of Tanks ……………………………………………………………… 5
Pump Output & Rate Formulas ………………………………………………………………. 6
Pump Pressure Relationships …………………………………………………………………. 6
Equivalent Circulating Density ………………………………………………………………. 7
Trip Calculations ………………………………………………………………………………….. 7
Pressure & Gradient Formulas ……………………………………………………………….. 8
Kick Related Formulas & Equations
Kill Sheet Calculations ………………………………………………………………………….. 9
Kick Related Formulas ………………………………………………………………………… 10
Kick Related Engineering Calculations …………………………………………………. 11
Volumetric Method Calculations ………………………………………………………….. 12
Lubricate & Bleed Calculations ……………………………………………………………. 12
Stripping / Snubbing Calculations …………………………………………………………. 14
Subsea Formulas ………………………………………………………………………………… 15
Accumulator Sizing …………………………………………………………………………….. 15
Mud & Cement Formulas …………………………………………………………………….. 16
Hydraulics Formulas …………………………………………………………………………… 18
Estimates & Rules of Thumb
Tripping …………………………………………………………………………………………….. 18
Stuck Pipe ………………………………………………………………………………………….. 19
Free Point and Stretch Estimates …………………………………………………………… 20
Temperature Drop Across Choke or Orifice …………………………………………… 21
Bit Nozzle Pressure Loss ……………………………………………………………………… 21
Gas Well Flow Rates …………………………………………………………………………… 22
Area of a Circle ………………………………………………………………………………….. 22
Force and Pressure ……………………………………………………………………………… 23
Weight of Spiral Drill Collars ………………………………………………………………. 23
Buoyancy Factor ………………………………………………………………………………… 23
Surface and Bottom Hole Pressures in Full Gas Column …………………………. 23
Pipe Elongation Due to Temperature …………………………………………………….. 24
Pipe, BOP & Other Data Tables
Drillpipe – Range II …………………………………………………………………………….. 26
Drillpipe Capacity & Displacement ………………………………………………………. 27
Heavy-Weight Drillpipe ………………………………………………………………………. 28
Drill Collars ……………………………………………………………………………………….. 29
Drill Collar Capacity & Displacement …………………………………………………… 31
KILL SHEET ……………………………………………………………………………………. 32
API Tubing ………………………………………………………………………………………… 34
Casing Strength ………………………………………………………………………………….. 42
Casing Capacity ………………………………………………………………………………….. 45
Hole Capacity …………………………………………………………………………………….. 47
Triplex Pumps at 100% Efficiency ……………………………………………………….. 48
Mud Weights ……………………………………………………………………………………… 51
Specifications for BOP Flanges, etc. …………………………………………………….. 53
Gate Valve Data …………………………………………………………………………………. 54
API Ring Joint Flanges ……………………………………………………………………….. 56
BOP Fluid Operating Volumes …………………………………………………………….. 59
Coiled Tubing Data …………………………………………………………………………….. 65
Coiled Tubing Dimensions …………………………………………………………………… 66
Electric Line ………………………………………………………………………………………. 68
Wireline Data …………………………………………………………………………………….. 70
Conversion Factors ……………………………………………………………………………… 71

Some example pages from the book.

## IWCF Well Control Quizzes

My friend just sent me the very useful well control stuff again. This time is the IWCF well control quizzes by Transocean which use to train their people. The well control quizzes each contain 25 questions and are grouped into related topic areas ranging from fairly basic knowledge through to some of the harder calculations that supervisors may come across in their IWCF exam.

There are a total of 8 modules as follows:

1. Basic knowledge in well control

2. Basic pressure (hydrostatic pressure)

3. Warning signs and shut in

4. Shut in conditions

5. Volume and MAASP (Maximum Allowable Anticipated Surface Pressure)

6. Well control methods

7. Some tricky well control questions

8. Subsea well control questions

If you are interested in these handy well control quiz, please click at the image or the link below

http://bit.ly/IecVXk

Additional information: IWCF stands for The International Well Control Forum which is an oil industry Membership Organization established in Europe in 1992. Its primary purpose is to develop and administer well control certification programs for personnel employed in oil well Drilling, Workover and Well Intervention operations.

## Useful Well Control Handouts from Texas A&M University

Petroleum engineering department at Texas A&M University has a strong technical in every aspect of oilfield. This is the one of top petroleum engineering universities in USA. Today, I find the very useful well control documents which are used to teach students at the university. There are several topics in the well control. If you are interested in these excellent well control handouts, please check out the following links to download them.

I wish you would enjoy the well control lectures.