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Introduction to Directional Drilling

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Introduction to Directional Drilling Subject Matter Experts: Raymond de Verteuil and Iain McCourt

Sugar Land Learning Center 1998, revised 2001

An asterisk (*) is used throughout this module to denote a mark of Schlumb erger  Copyright Schlumberger Technology Corp., unpublished work, created 1998, reviewed 2001. The following material includes Confidential, Proprietary Information and is a trade secret of Schlumberger Technology Corp. All use, disclosure, and/or reprod uction is prohibited unless authorized in writing. All rights reserved. This material may also be protected under laws of non -U.S. countries, including copyright and trade secret laws. Source: IntroToDD.pdf, Revised 6/13/01, SLC


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Objectives In this module you will learn to do the following: 1. Define directional drilling by choosing the correct answer from a list of selections. 2. Recall the historical development of directional drilling by choosing the correct answer from a list of selections. 3. Recognize the reasons for drilling the following types of wells: exploration, appraisal, development/production. 4. Identify descriptions and pictures of directional drilling applications. 5. Identify several features of a directional well profile. 6. Identify the general types of directional well profiles. 7. Recall an explanation of a well plan by choosing an answer from a list of selections. 8. Identify the basic components of a well plan.

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1 Introduction Directional drilling has become a very important tool in the development of oil and gas deposits. Current expenditures for hydrocarbon production have dictated the necessity of controlled directional drilling to a much larger extent than previously.

Probably the most important aspect of controlled directional drilling is that it enables producers all over the world to develop subsurface deposits that could never be reached economically in any other manner. In this module a number of topics will be covered that must be understood by the directional driller. The various types of wells and applications of directional wells will be touched upon along with well profiles and well planning.

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2 Directional Drilling In this lesson you will learn to do the following: Define directional drilling by choosing the correct answer from a list of selections. Recall the historical development of directional drilling by choosing the correct answer from a list of selections. 2.1 Definition of Directional Drilling Controlled directional drilling is the science and art of deviating a wellbore along a planned course from a starting location to a target location, both defined with a given coordinate system. 2.2 Description of Directional Drilling Drilling a directional well basically involves drilling a hole from one point in space (the surface location) to another point in space (the target) in such a way that the hole can then be used for its intended purpose. A typical directional well starts off with a vertical hole, then kicks off so that the bottom hole location may end up hundreds or thousands of feet or meters away from its starting point.

With the use of directional drilling, several wells can be drilled into a reservoir from a single platform.

2.3 Historical Development of Directional Drilling Directional drilling was initially used as a remedial operation, either to sidetrack around stuck tools, bring the wellbore back to vertical, or in drilling relief wells to kill blowouts. Interest in controlled directional drilling began about 1929 after new and rather accurate means of measuring the hole angle were introduced during the development of the Seminole field, Oklahoma, USA.

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Historical Development of Directional Drilling In 1930, the first controlled directional well was drilled in Huntington Beach, California, USA. The well was drilled from an onshore location into offshore oil sands. Controlled directional drilling had received rather unfavorable publicity until it was used in 1934 to kill a wild well near Conroe, Texas, USA. As a result, directional drilling became established as one way to overcome wild wells, and it subsequently gained favorable recognition from both companies and contractors.

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Study Questions 1) Which of the following is the correct definition for directional drilling? a) The science and art of deviating a wellbore along a planned course to a surface target location that is a given lateral distance and direction from the horizontal b) The science and art of deviating a wellbore along a planned course to a subsurface target location that has not been Determined c) The science and art of deviating a wellbore along a planned course to a subsurface target location that is a given vertical distance and direction from the horizontal d) The science and art of deviating a wellbore along a planned course from a surface location to a target location, both defined with a given coordinate system

2) Which of the following is the most important aspect of controlled directional drilling? a) It enables producers all over the world to develop subsurface deposits that could never be reached economically in any other manner. b) It is the science of deviating a wellbore along a planned course to a surface target location that is a given lateral distance and direction from the horizontal. c) It enables producers all over the world to develop subsurface deposits that could have been lost due to improper drilling equipment. d) It enables producers all over the world to kill wild wells.

3) Directional drilling was used initially for remedial operations. Which of the following are examples of these earlier uses? Select all the correct answers. a) b) c) d) e)

To drill relief wells to kill blowouts To sidetrack around stuck tools To bring the wellbore back to vertical For salt dome drilling For offshore multiwell drilling

4) Where was the first controlled directional well drilled in 1930? a) b) c) d)

Conroe, Texas Huntington Beach, California Seminole field, Oklahoma Long Beach, California

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3 Types of Wells In this lesson you will learn to do the following: Recognize the reasons for drilling the following types of wells: exploration, appraisal, development/production. 3.1 Three General Types of Wells Wells are generally classified as exploration wells, appraisal wells, and development wells/production wells. Exploration wells, sometimes called wildcat wells, probe the earth where no known hydrocarbons exist to determine whether oil or gas are present in a subsurface rock formation. Appraisal wells are drilled to determine the extent of a field or the amount of area it covers. Development or Production wells are drilled in an existing field to remove the obtainable hydrocarbons.

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Study Questions 1) Exploration wells are drilled for which of the following reasons? Select all the correct answers. a) b) c) d) e)

To produce an existing field To determine the extent of a field To determine whether oil or gas exists in a subsurface rock formation To probe the earth where no known hydrocarbons exist To reach a reservoir that is in excess of 15,000 ft

2) Appraisal wells are drilled for which of the following reasons? Select all the correct answers. a) b) c) d) e)

To determine the extent of a field To probe the earth where no known hydrocarbons exist To produce an existing field To determine how much area a field covers To reach a reservoir that is in excess of 15,000 ft

3) Development wells/Production wells are drilled for which of the following reasons? a) b) c) d)

To probe the earth where no known hydrocarbons exist To remove hydrocarbons from an existing field To determine the extent of a field To reach a reservoir that is in excess of 15,000 ft

4) Match each well with its reason for being drilled. a) To determine whether oil or gas exists in a subsurface rock formation b) To remove hydrocarbons from an existing field c) To determine the extent or area of coverage of a field 1) Exploration wells 2) Development wells/Production wells 3) Appraisal wells

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4 Directional Well Applications In this lesson you will learn to do the following: Identify descriptions and pictures of directional drilling applications. 4.1 Sidetracking Sidetracking was the original directional drilling technique used to get past fish (obstructions). Oriented sidetracks, the most common type of sidetracking, are performed when there are unexpected changes in geology and obstructions in the path of the wellbore.

4.2 Inaccessible Locations Inaccessible locations such as targets located beneath cities, rivers or environmentally sensitive areas make it necessary to locate the drilling rig some distance away from the target.

4.3 Salt Dome Drilling Salt domes have been found to be natural traps of hydrocarbons accumulating beneath the overhanging hard cap. A directional well is used to reach the trapped reservoir to prevent the problems associated with drilling a well through the salt formation.

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4.4 Fault Controlling Fault controlling is an application used to drill a directional well into faulted subsurface formations without crossing the fault line.

4.5 Multiple Exploration Wells from A Single Wellbore Multiple exploration wells from a single wellbore use a single hole to drill multiple new wells by deviating away from the original well at a certain depth. It allows the exploration of structural locations without drilling another complete well.

4.6 Onshore Drilling to Offshore Locations Onshore drilling takes place when a reservoir is located below large bodies of water that are within drilling reach of land. The wellheads are located on land, and the borehole is drilled directionally underneath the water to reach the reservoir. This technique saves money because land rigs are much cheaper than offshore rigs.

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Study Questions 1. Which of the following are reasons for drilling a directional well? Select all the correct answers. a) b) c) d) e)

To get to trapped oil beneath salt domes To get to a target located beneath a city or a sensitive area To get past a fish To reach a reservoir located below large bodies of water To allow for exploration without drilling other complete wells

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4.7 Offshore Multiwell Drilling Offshore multiwell drilling is the most economical way to develop offshore fields. Several directional wells are drilled in "clusters" on a multiwell offshore platform.

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Study Question 2) Which of the following directional drilling applications is the most economical way to develop an oil field that is below a large body of water but within drilling reach of land? a) b) c) d)

Offshore multiwell drilling Offshore drilling to onshore locations Onshore drilling to offshore locations Multiple exploration wells from a single offshore wellbore

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4.8 Relief Wells Relief wells are used to kill wells that are blowing by intercepting the borehole. A carefully planned directional well must be drilled with great precision to locate and intercept the blowing well’s borehole.

4.9 Horizontal Wells Horizontal wells are used to intersect a producing formation horizontally to better produce the reservoir. Horizontal drilling increases the surface area of a producing formation. For example, a vertical well may give exposure to a reserve with a depth of 20 to 30 ft (6 to 10 m) while a horizontal well drilled into the same reservoir may give exposure to 2000 to 3000 ft (600 to 1000 m). Horizontal wells can make a platform profitable, where it was not previously.

4.10 Extended Reach Wells Extended reach wells are drilled to reach reservoirs that have a horizontal displacement in excess of 16,400 ft (> 5,000 m) from the starting point.

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4.11 Multilateral Wells Multilateral wells have several wellbores running laterally and originating from one original hole.

4.12 Short, Medium, and Long Radius Wells Short radius wells, typically re-entries of old vertical wells, have curves with a 143 ft (44 m) radius or smaller that cannot be drilled with conventional motors. They are used to isolate higher-/lower-pressured production zones or water sands without setting and cementing a liner. This type of drilling is desirable when kicking off below a problem formation. Medium radius wells have curves with a 200-500 ft (61-152 m) radius that can be drilled with conventional motors. Long radius wells have curves with a 750 ft (229 m) radius or larger that can also be drilled with conventional motors.

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Study Questions 3) Which of the following are applications for drilling a directional well? Select all the correct answers. a) b) c) d) e)

Onshore drilling to offshore locations Relief wells Offshore multiwell drilling Horizontal wells Multiple exploration wells from a single wellbore

4) Which of the following are applications for drilling a directional well? Select all the correct answers. a) b) c) d) e)

Sidetracking Salt dome drilling Offshore drilling to onshore locations Fault controlling Inaccessible locations

5) Which of the following is the best description of a directional drilling application that is used specifically to kill a well that is blowing? a) b) c) d)

Salt dome drilling Horizontal wells Offshore multiwell drilling Relief wells

6) Which of the following is the best description of a directional drilling application that is used specifically to intersect a producing formation horizontally to better produce the reservoir? a) b) c) d)

Onshore drilling to offshore locations Offshore multiwell drilling Horizontal wells Relief wells

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7) Identify each picture with its directional drilling application. a) Sidetracking b) Inaccessible location c) Salt dome drilling

8) Identify each picture with its directional drilling application. a) Onshore drilling to offshore location b) Fault controlling c) Offshore multiwell drilling

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9) Identify each picture with its directional drilling application. a) Horizontal well b) Multilateral well c) Relief well

10) Identify each picture with its directional drilling application. a) Extended reach wells b) Fault controlling c) Short radius wells

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11) Extended reach wells are drilled to reach reservoirs that are in excess of _____ meters from the starting point. a) b) c) d)

500,000 5,000 500 50

?

12) Which of the following would apply to short radius directional drilling? Select all the correct answers. a) Used to isolate higher-/lower-pressured production zones or water sands without setting and cementing a liner b) Typically reentries of old vertical well c) Has curves with a 200 to 500 ft radius d) Has curves with a 143 ft radius or smaller that cannot be drilled with conventional motors

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5 Directional Well Profiles In this lesson you will learn to do the following: Identify several features of a directional well profile. Identify the three general types of directional well profiles.

5.1 Features of A Directional Well Profile A directional well profile is the planned well trajectory from the surface to the final drilling depth by projecting the wellbore onto two plotted planes. In order to determine the best geometric well profile from the surface to the bottomhole target, the following information must be known • the position of the surface location, • the position of the target location, and • the true vertical depth (TVD). A directional well profile is the planned well trajectory from the surface to the final drilling depth by projecting the wellbore onto two plotted planes. In order to determine the best geometric well profile from the surface to the bottomhole target, the following information must be known the position of the surface location, the position of the target location, and the true vertical depth (TVD).

A directional well profile is the planned well trajectory from the surface to the final drilling depth by projecting the wellbore onto two plotted planes. In order to determine the best geometric well profile from the surface to the bottomhole target, the following information must be known the position of the surface location, the position of the target location, and the true vertical depth (TVD).

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5.1.2 Kickoff Point (KOP) The kickoff point is the location at a given depth below the surface where the wellbore is deviated in a given direction.

5.1.3 Well Inclination The well inclination is the angle by which the wellbore deviates from the vertical.

5.1.4 End of Buildup (EOB) The end of buildup is the location where the wellbore has finished increasing.

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5.1.5 Hold Angle The hold angle occurs where the inclination of the borehole is held constant.

5.1.6 Tangent Section The tangent section (hold section) occurs after a buildup where the inclination of the borehole is held constant for a certain distance. There could be an additional build or drop before reaching the target.

5.1.7 Start of Drop The start of drop is the location where the wellbore starts dropping inclination.

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5.1.8 End of Drop (EOD) The end of drop is the location where the wellbore finishes dropping inclination.

5.1.9 Target Displacement The target displacement is the lateral distance from the surface location to the target.

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Study Question 1) Write in the correct term to correctly complete the following sentence. A well profile is the planned well trajectory from the ____________________ to the final drilling depth.

2) Which of the following must be known to determine the best geometric well profile from the surface to the bottomhole target? Select all the correct answers. a) b) c) d)

The TVD of the target The position of the surface location The position of the target location The density of the target

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5.1.10 Target Location The target location is a point defined in space by geographical coordinates at a given true vertical depth. A well profile could have multiple targets. 5.1.11 Drop Off Rate (DOR) The drop off rate is the rate at which the inclination decreases. The rate is usually expressed in degrees per 100 ft or degrees per 30 m of the course length.

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Study Question 3) Identify the features of a directional well profile. a) b) c) d) e)

Surface Location Tangent Section KOP Hold Angle Target Location

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5.1.12 Buildup Rate (BUR) The buildup rate is the change of inclination of a wellbore where the angle is increased. The rate is usually expressed in degrees per 100 ft or angular increase per 30 m of the measured depth. 5.1.13 Turn Rate The turn rate determines the rate a well profile turns in azimuth direction. Usually expressed in degrees per 100 ft or degrees per 30 m.

True Vertical Depth (TVD) The true vertical depth of any point or station along a wellbore is the vertical distance from the well surface reference point to the station of interest.

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Measured Depth (MD) The measured depth of any point or station along a wellbore is the distance from the well surface reference point to the station of interest along the actual well path.

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Page 31 of 52 Horizontal Displacement (HD) The horizontal displacement is the distance between any two points along a wellbore projected onto a horizontal plane or plan view.

Vertical Section (VS) The vertical section is the distance between any two points along a wellbore projection onto a vertical section plane.

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Page 32 of 52 Azimuth The azimuth is the angle in the horizontal plane measured from a fixed reference direction (such as True North), usually measured clockwise.

5.1.19 Quadrant The quadrant bearing of a well is the angle in the horizontal plane measured from either a North or South reference direction towards the East or West, defining the direction of the wellbore.

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5.1.20 Polar Coordinate The polar coordinate of a point is the distance projected in a horizontal plane from a fixed reference point and the angle of this line from a reference direction (usually True North).

5.1.21 Rectangular Coordinate The rectangular coordinates of a point are defined as the projected distance along two reference axes which are at right angles, the distance being measured from the intersection of the axes along the axes. These axes reside in the horizontal plane and typically are north/south and east/west directions.

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Study Questions

4) Match each well profile feature with its definition. a) The geographical position on earth where the well starts b) The location at a given depth below the surface where the wellbore is deviated in a given direction c) The change of inclination of a wellbore where the angle is increased d) Determines the rate a well profile turns in azimuth direction 1) 2) 3) 4)

Kickoff Point Surface Location Buildup Rate Turn Rate

5) Match each well profile feature with its definition. a) b) c) d)

Occurs where the inclination of the borehole is held constant The location where the wellbore starts dropping inclination The angle by which the wellbore deviates from the vertical The change of inclination of a wellbore where the angle is purposely reduced 1) 2) 3) 4)

Well Inclination Drop Off Rate Hold Angle Start of Drop

6) Match each well profile feature with its definition. a) The actual measured vertical depth from a reference point on the surface to a point of interest b) The lateral distance from the surface location to the target c) Direction of a course measured in a clockwise direction from 0-360o referred to North d) The length of the projection of the horizontal displacement onto the vertical section plane defined by its azimuth. 1) 2) 3) 4)

True Vertical Depth Target Displacement Vertical Section Azimuth

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7) Match each well profile feature with its definition. a) b) c) d)

The actual length of the wellbore from its surface location to any specified station The distance between two points that are projected onto a horizontal plane A point where a well profile finished dropping inclination The point or location of the oil and gas reservoirs

e) f) g) h)

Measured Depth Target Horizontal Displacement End of Drop

6) Match each well profile feature with its definition. a) Occurs after a buildup where the inclination of the borehole is held constant for a certain distance b) The azimuth angle measured from North or South in the direction of East or West c) A point defined by a distance and a direction relative to North d) Used to give a target's position in feet or meters with direction of North/South and East/West e) The location where the wellbore has finished increasing 1) 2) 3) 4) 5)

Tangent Section Polar Coordinate Rectangular Coordinate Quadrant End of Buildup

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5.2 Types of Directional Well Profiles In general, directional wells can be either: • • • •

Straight (Vertical), S-type, Slant (J-type), or Horizontal.

The type of profile selected will depend upon the geological objectives and the production mechanism of the well. 5.2.1 Straight Well (Vertical) Straight wells have a bore with no planned deviation from vertical.

5.2.2 S-Type Well S-type wells have a bore with a straight section, a build section, a tangent section, and a drop section. This type of well is drilled to improve the efficiency of the well and to assist in the location of a blown-out well. In offshore drilling, S-type wells can ensure accuracy in bottomhole spacing when multiple wells are drilled from the same platform.

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5.2.3 Slant Well (J-Type) Slant wells, sometimes called J-type wells, have a bore with a straight section, a build section, and a tangent section straight to the target Slant or J-type wells are drilled where it is not desirable or possible to locate the surface location directly above the target or a multiwell platform.

5.2.4 Horizontal Well Horizontal wells have a bore with a straight section, a build section, tangent section, a second build section (most of the time), and a horizontal section. The well is drilled to a point above the reservoir; then it is deflected and the angle increases until it reaches 90 degrees or more. When properly applied, one horizontal borehole can produce a reservoir better than several vertically drilled wells.

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Study Questions 8) Match each well profile feature with its definition. a) Occurs after a buildup where the inclination of the borehole is held constant for a certain distance b) The azimuth angle measured from North or South in the direction of East or West c) A point defined by a distance and a direction relative to North d) Used to give a target's position in feet or meters with direction of North/South and East/West e) The location where the wellbore has finished increasing 1) 2) 3) 4) 5)

Tangent Section Polar Coordinate Rectangular Coordinate Quadrant End of Buildup

9) Which of the following are general types of directional well profiles? Select all the correct answers. a) b) c) d)

Straight Slant S-type Horizontal

10) This graphic represents which of the following types of directional well profiles. a) b) c) d)

Straight well Horizontal well S-type well Slant well

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6 Well Planning In this lesson you will learn to do the following: Recall an explanation of a well plan by choosing an answer from a list of selections. Identify the basic components of a well plan. 6.1 Definition of A Well Plan Well planning is an organized process used to put together data that will be used to design a successful well. A well plan is a very important stage prior to the commencement of the drilling operation to ensure that all aspects are tailored to meet the specific objectives of that well. Anadrill well plans are often developed in a Drilling Engineering Center (DEC) by a well planner. Understanding how to design a well plan (proposal), is one of the most important duties of the directional driller. He must be able to understand the plan and make any required changes. The data provided by the client is used by the well planner to develop a geometric profile for the safest and easiest path from the surface location to the target. The planner has access to a computer program to help develop the best possible profile. The needed data is put into the program so that a well profile can be printed, plotted and used for the drilling project. 6.2 Components of a Well Plan There are many components to take into consideration when designing a successful well plan. The well planning components listed here are the same as the features of a well profile found in section 5.1. If you do not recall these terms, please refer back to section 5.1. Components of a Well Plan • • • • • • • • • • •

Surface Location Target Location Kickoff Point Buildup Rate Turn Rate Hold Angle Start of Drop True Vertical Depth Target Displacement Azimuth Vertical Section

• • • • • • • • • •

Quadrant Polar Coordinate Rectangular Coordinate End of Drop Tangent Section Measured Depth Well Inclination End of Buildup Horizontal Displacement Drop Off Rate

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Study Questions 1) Write in the correct terms to correctly complete the following sentence. Well planning is an important stage prior to the commencement of actual drilling operations to ensure that all aspects of the well are tailored to meet the specific _________________________ of that well.

2) Which of the following are components of a well plan? Select all the correct answers. a) b) c) d) e) f) g)

Drop Quadrant Azimuth Quadrant Rectangular Coordinate End of Well Vertical Section Polar Coordinate

3) Which of the following are components of a well plan? Select all the correct answers. a) b) c) d) e) f) g) h)

Hold Angle Depth Control Kickoff Point Buildup Rate Surface Location Start of Drop True Value Down Turn Rate

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7 Summary Directional drilling has become a very important drilling process. It has enabled producers all over the world to develop subsurface deposits that could never have been reached economically in any other manner. In this module, directional drilling was defined along with its historical development. The applications of a directional well as well as the features of a well profile were also covered. The module also included information on the types of well profiles and the components of a well plan.

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7 Answers to Study Questions

PART 1 No Study Questions Part 2 1) Which of the following is the correct definition for directional drilling? a) The science and art of deviating a wellbore along a planned course to a surface target location that is a given lateral distance and direction from the horizontal b) The science and art of deviating a wellbore along a planned course to a subsurface target location that has not been Determined c) The science and art of deviating a wellbore along a planned course to a subsurface target location that is a given vertical distance and direction from the horizontal d) The science and art of deviating a wellbore along a planned course from a surface location to a target location, both defined with a given coordinate system

2) Which of the following is the most important aspect of controlled directional drilling? a) It enables producers all over the world to develop subsurface deposits that could never be reached economically in any other manner. b) It is the science of deviating a wellbore along a planned course to a surface target location that is a given lateral distance and direction from the horizontal. c) It enables producers all over the world to develop subsurface deposits that could have been lost due to improper drilling equipment. d) It enables producers all over the world to kill wild wells.

3) Directional drilling was used initially for remedial operations. Which of the following are examples of these earlier uses? Select all the correct answers. a) b) c) d) e)

To drill relief wells to kill blowouts To sidetrack around stuck tools To bring the wellbore back to vertical For salt dome drilling For offshore multiwell drilling

4) Where was the first controlled directional well drilled in 1930? a) b) c) d)

Conroe, Texas Huntington Beach, California Seminole field, Oklahoma Long Beach, California

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Part 3 5) Exploration wells are drilled for which of the following reasons? Select all the correct answers. a) b) c) d) e)

To produce an existing field To determine the extent of a field To determine whether oil or gas exists in a subsurface rock formation To probe the earth where no known hydrocarbons exist To reach a reservoir that is in excess of 15,000 ft

6) Appraisal wells are drilled for which of the following reasons? Select all the correct answers. a) b) c) d) e)

To determine the extent of a field To probe the earth where no known hydrocarbons exist To produce an existing field To determine how much area a field covers To reach a reservoir that is in excess of 15,000 ft

7) Development wells/Production wells are drilled for which of the following reasons? a) b) c) d)

To probe the earth where no known hydrocarbons exist To remove hydrocarbons from an existing field To determine the extent of a field To reach a reservoir that is in excess of 15,000 ft

8) Match each well with its reason for being drilled. a) To determine whether oil or gas exists in a subsurface rock formation (1) b) To remove hydrocarbons from an existing field (2) c) To determine the extent or area of coverage of a field (3) 1) Exploration wells 2) Development wells/Production wells 3) Appraisal wells

Part 4 1) Which of the following are reasons for drilling a directional well? Select all the correct answers a) b) c) d) e)

To get to trapped oil beneath salt domes To get to a target located beneath a city or a sensitive area To get past a fish To reach a reservoir located below large bodies of water To allow for exploration without drilling other complete wells Source: SLC IntroTo DD.doc Revised: 10/20/98 6:37 AM


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2) Which of the following directional drilling applications is the most economical way to develop an oil field that is below a large body of water but within drilling reach of land? a) b) c) d)

Offshore multiwell drilling Offshore drilling to onshore locations Onshore drilling to offshore locations Multiple exploration wells from a single offshore wellbore

3) Which of the following are applications for drilling a directional well? Select all the correct answers. a) b) c) d) e)

Onshore drilling to offshore locations Relief wells Offshore multiwell drilling Horizontal wells Multiple exploration wells from a single wellbore

4) Which of the following are applications for drilling a directional well? Select all the correct answers. a) b) c) d) e)

Sidetracking Salt dome drilling Offshore drilling to onshore locations Fault controlling Inaccessible locations

5) Which of the following is the best description of a directional drilling application that is used specifically to kill a well that is blowing? a) b) c) d)

Salt dome drilling Horizontal wells Offshore multiwell drilling Relief wells

6) Which of the following is the best description of a directional drilling application that is used specifically to intersect a producing formation horizontally to better produce the reservoir? a) b) c) d)

Onshore drilling to offshore locations Offshore multiwell drilling Horizontal wells Relief wells

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7) Identify each picture with its directional drilling application. a) Sidetracking (3) b) Inaccessible location (2) c) Salt dome drilling (1)

8) Identify each picture with its directional drilling application. a) Onshore drilling to offshore location (3) b) Fault controlling (2) c) Offshore multiwell drilling (1)

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9) Identify each picture with its directional drilling application. a) Horizontal well (3) b) Multilateral well (2) c) Relief well (1)

10) Identify each picture with its directional drilling application. a) Extended reach wells (2) b) Fault controlling (1) c) Short radius wells (3)

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11) Extended reach wells are drilled to reach reservoirs that are in excess of _____ meters from the starting point. a) b) c) d)

500,000 5,000 500 50

?

12) Which of the following would apply to short radius directional drilling? Select all the correct answers. a) Used to isolate higher-/lower-pressured production zones or water sands without setting and cementing a liner b) Typically reentries of old vertical well c) Has curves with a 200 to 500 ft radius d) Has curves with a 143 ft radius or smaller that cannot be drilled with conventional motors

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Part 5 11) Write in the correct term to correctly complete the following sentence. A well profile is the planned well trajectory from the ____surface_________ to the final drilling depth.

12) Which of the following must be known to determine the best geometric well profile from the surface to the bottomhole target? Select all the correct answers. a) b) c) d)

The TVD of the target The position of the surface location The position of the target location The density of the target 13) Identify the features of the directional well profile. a) End of Buildup (1) b) Start of Drop (2) c) End of Drop (3) d) Target Displacement (4) e) Well Inclination (5)

14) Match each well profile feature with its definition. a) The geographical position on earth where the well starts b) The location at a given depth below the surface where the wellbore is deviated in a given direction c) The change of inclination of a wellbore where the angle is increased d) Determines the rate a well profile turns in azimuth direction 1) 2) 3) 4)

Kickoff Point (b) Surface Location (a) Buildup Rate (c) Turn Rate (d)

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15) Match each well profile feature with its definition. a) b) c) d)

Occurs where the inclination of the borehole is held constant The location where the wellbore starts dropping inclination The angle by which the wellbore deviates from the vertical The change of inclination of a wellbore where the angle is purposely reduced 1) 2) 3) 4)

Well Inclination (c) Drop Off Rate (d) Hold Angle (a) Start of Drop (b)

16) Match each well profile feature with its definition. a) b) c) d)

The actual measured vertical depth from a reference point on the surface to a point of interest The lateral distance from the surface location to the target Direction of a course measured in a clockwise direction from 0-360o referred to North The length of the projection of the horizontal displacement onto the vertical section plane defined by its azimuth. 1) 2) 3) 4)

True Vertical Depth (a) Target Displacement (b) Vertical Section (d) Azimuth (c)

17) Match each well profile feature with its definition. a) b) c) d)

The actual length of the wellbore from its surface location to any specified station The distance between two points that are projected onto a horizontal plane A point where a well profile finished dropping inclination The point or location of the oil and gas reservoirs 1) 2) 3) 4)

Measured Depth (a) Target (d) Horizontal Displacement (b) End of Drop (c)

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18) Match each well profile feature with its definition. a) b) c) d) e)

Occurs after a buildup where the inclination of the borehole is held constant for a certain distance The azimuth angle measured from North or South in the direction of East or West A point defined by a distance and a direction relative to North Used to give a target's position in feet or meters with direction of North/South and East/West The location where the wellbore has finished increasing 1) 2) 3) 4) 5)

Tangent Section (a) Polar Coordinate (c) Rectangular Coordinate (d) Quadrant (b) End of Buildup (e)

19) Which of the following are general types of directional well profiles? Select all the correct answers. a) b) c) d)

Straight Slant S-type Horizontal

20) This graphic represents which of the following types of directional well profiles. a) b) c) d)

Straight well Horizontal well S-type well Slant well

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Part 6 1) Write in the correct terms to correctly complete the following sentence. Well planning is an important stage prior to the commencement of actual drilling operations to ensure that all aspects of the well are tailored to meet the specific ______objectives__________ of that well.

2) Which of the following are components of a well plan? Select all the correct answers. a) b) c) d) e) f) g)

Drop Quadrant Azimuth Quadrant Rectangular Coordinate End of Well Vertical Section Polar Coordinate

3) Which of the following are components of a well plan? Select all the correct answers. a) b) c) d) e) f) g) h)

Hold Angle Depth Control Kickoff Point Buildup Rate Surface Location Start of Drop True Value Down Turn Rate

Source: SLC IntroTo DD.doc Revised: 10/20/98 6:37 AM


Introduction to Directional Drilling

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Source: SLC IntroTo DD.doc Revised: 10/20/98 6:37 AM

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