Vertical section calculation directional drilling. Planned build up rate = 2 degree/100 ft. I2 = inclination (angle) at lower in degrees. Loads applied by tension, torsion, combined tension and torsion, burst pressure, collapse pressure, slip crushing, and stability forces are considered. 5 Drilling Fluid Management Plan: Indicate the type and amount of the drilling fluid planned to be used on the project. You can calculate North, East and TVD between directional surveys based on the Angle Averaging Method as per formula below: Where; MD = measured depth between surveys in ft. Drilling Engineer incorporates both Well Plan and Casing Design so you can now design and plan your well bore trajectory and export the planned survey to Casing Design you save $500 with the new program. The following formula provides dogleg severity in degrees/100 ft and is based on the Tangential Method: Dogleg severity (DLS) = 100 ÷ {MD x [ (sin I1 x sin I2) x (sin Az1 x sin Az2 + cos Az1 x cos Az2) + (cos I1 x cos I2)]} where. Azimuth References. The user can input the length of each section either by measured depth (MD) length or true vertical depth (TVD) length We would like to show you a description here but the site won’t allow us. 5 pounds per gallon will exert around 13. 7 Drilling Fluid Pressure Calculations: Provide documentation sealed by a Nevada registered professional engineer for the calculations of minimum required and maximum allowable Oct 30, 2017 · The distance is BB3 (between Survey tip end “z” axis). The vertical section is the horizontal distance from the centerline of a wellbore to a certain point on a well trajectory, measured along a pre-defined azimuth in horizontal plan. Surveying can be performed while drilling occurs or after it has been completed. 31 feet. Examples: Slanted holes, high angle holes (far from vertical), and Horizontal holes. Lyons, Norton J. True Distance (ft) = True Distance (m) x 3. Ensure that the drill remains perpendicular to the pipe's surface. Com | August 22, 2010 - 1:57 am | November 14, 2011 Directional Training, Drilling Engineering Calculations 4 Comments Aforementioned tangential method is the simplest calculation among other directional online calculations . 6 However, there is an exception that the primary unknown in the combination trajectory Aug 2, 2016 · Directional well trajectory design is an essential part of a drilling plan process and requires rigorous mathematics to ensure proper execution of the drill path that would accommodate safety of Sep 1, 2010 · Among these methods, the minimum curvature method is accepted as the industry standard and widely used in the calculation of three-dimensional directional surveys for slide drilling systems the site layout is to include but not be limited to: drilling rig, mud system, drill rod stock pile and mud return pit. The advantage of directional drilling includes intersecting a liquid-bearing fracture at a more beneficial angle compared to a vertical intersection. Directional drilling, since its formal initiation, has always been a demanded approach for reaching remote subsurface crude accumulations. Feb 18, 2017 · The easiest type of directional well profile is a so-called “J-shaped profile”, which is a build and hold to the target. 0. Oct 30, 2017 · The inclination of a well is the angle (usually expressed in degrees) between the vertical and the borehole axis at a particular point. Nevertheless, on a practical note, the design and development cost of a directional well is reasonably high, and hence Jul 6, 2011 · The horizontal section is usually drilled at 90 degrees and therefore the extra maths involved is quite simple as we only need the measured length of the horizontal section to calculate the total well departure and total measured depth. Vertical section is the horizontal distance from the centerline of a Aug 30, 2016 · The vertical and directional drilling are the key technologies for the exploration and exploitation of oil and gas resources in deep formations. It can be broken down into three main groups: Oilfield Directional Drilling, Utility Jan 20, 2022 · Firstly, this paper analyzes the calculation method of pullback force in horizontal directional drilling; studies the calculation formula and principle of common pullback force through examples drilling took off, as directional drilling is able to plan and execute very difficult well paths [1]. Dec 3, 2018 · horizontal section. Survey uncertainty must also be computed for the proposed and critical existing wells. William C. 65 = 189. SECTION 02XXX HORIZONTAL DIRECTIONAL DRILL PART 1 GENERAL 1. Directional drilling is the methodology for directing a wellbore along a predetermined trajectory to a target. 999685 = 1504. 4 Holding assemblies: packed hole. Jun 1, 2015 · A horizontal directional drilling fluid that weighs 8. Tangent section. Section 3-25 - Directional Drilling. The proper selection of drilling mud motor specification for hole cleaning issues will be the multilobe motors, as they have a broader flow rate range and a much higher maximum allowable flow rate than 1:2 lobe PDMs of the same O. The maximum directional drilling deviation on the vertical direction is 0. Even “vertical” hole sometimes require directional drilling techniques. 97 ft. 3 Building assemblies: fulcrum principle. Drop-off section. The program allows you to design multiple directional trajectories,side tracks and well intervention for any well profile or import a trajectory; Vertical, Slant. Meanwhile, they are also the very important ways to exploit deep geothermal energy and geo-resources, conduct international continental scientific drilling program. 2 Rotary assemblies. The inclination vector lies in the vertical plane, while the azimuth lies in the horizontal plane. 63 m. By industry standard, 0 degree inclination is vertical (downward pointing) and 90 degrees inclination is horizontal. Successful directional Casing مقدمة مثال 1مثال 2 مثال 3 analyze the achievements of vertical and directional drilling in petroleum industry, the challenges of vertical and directional drilling are also discussed. path, and all existing utilities with dimensioned vertical and horizontal clearances. POWER SECTION The power section components include the rotor and the stator, which converts hydraulic energy of the drilling Sep 20, 2009 · What’s more, there is another way to calculate dogleg severity based on the concept of Tangential Method. Directional Drilling Survey Calculations Method and device increasing efficiency of drilling directional wells. 1 Definitions and terminology. Drilling optimization is an engineering strategy to drill wells more productively and efficiently. The purpose of directional survey is to: calculations, use of the TC plane in the calculation of the chosen rule does change the result, and can therefore affect real time directional drilling decisions. 91 ft. An inclination (angle) greater than 90 degrees coincides with the term "drilling up". The vertical reference is the direction of the local gravity vector and would be indicated by, for example, a plumb bob. 5 to 3° per foot (0. Moreover, directional drilling allows having multiple wells originating at the same surface location and deflecting into different directions (angles) as they go deeper. (a) Before beginning controlled directional drilling, other than whipstocking because of hole conditions, when the intent is to direct the bottom of the hole away from the vertical, notice of intention to do so shall be filed with the Supervisor and his approval obtained. Deviation is defined as departure of the wellbore from the vertical, measured by the horizontal distance from the rotary table to May 10, 2022 · Overcoming friction forces generated from the contact of tubulars with the wellbore is one of the most important challenges in directional drilling, hence the need to accurately predict these friction forces. 1 Bit side force. Inclination-. The last element is the vertical section from 5000’ to surface. A downhole drilling motor is also often referred to as a mud motor, steerable motor, bent motor assembly, directional motor, and drilling motor. 30 - 288. 38 m, and horizontal direction is 0. Convert from meter to feet. Vertical Section on the vertical plot, N/S vs. Inclination values varies from 0° (for vertical well) to 90° (for horizontal well). 00N 415,456. Vertical wells are usually defined as wells with an inclination within 5°. The tabular printout for this Only then can the latest bottom-hole coordinates be plotted on the directional well plot (TVD vs. The well trajectory is a three-dimensional path that a wellbore takes when drilled and is a function of three variables: the inclination, the azimuth, and the build rate. Specific objectives of directional drilling are good hole quality, firm directional control, high angle-build capacity, maximal durability, optimal rate of penetration (ROP) and low non-productive time (NPT). When the steering drilling system is used, it is easier to control the wellpath and drilling modes (for the sliding steering drilling system) or drilling Dec 11, 2023 · To calculate the total TVD, you will add the vertical depth of the first section to the vertical depth of the second section, and then subtract the horizontal distance of the second section from the horizontal distance of the first section. Slowly rotate the drill in a circular motion while maintaining a constant speed and pressure. 4. From this initial condition and as the bit advances, the BHA deflection and contact points are iteratively calculated according to the previously described methods, and the resulting angular direction of the bit element Basic Terminologies. In this section the following symbols will be used. Mar 22, 2016 · The drilling simulation proceeds from an initial prestraining of the BHA within a straight, vertical wellbore section. At a predetermined depth, the well is kicked off and, the angle is built to a 90 ° inclination. Directional drilling operations have a potential to inadvertently release fluids into the surface through frac‐outs. A hole deviation log, the details of which are discussed later in this paper, succinctly conveys hole deviation. Jun 6, 2017 · This distance must be applied the scale factor in order to get the true distance. Frac‐ outs occur when drilling fluid is released through fractured bedrock into the surrounding rock and sand and eventually travels toward the surface. The drilling fluid Nov 5, 2017 · The drill pipe in the tangent section from 9600’ – 5600’ is also taken as one element for the same reason. The formulation thereof in the study by Inglis (1987) is used in this research study when the methods of directional drilling calculations are presented in Appendix A. Abstract. Directional Drilling Books HDD Plan. DLS Directional drilling. Quickly compute an optimized directional drilling profile with minimal user input towards maximum understandable results. May 4, 2020 · 1. Where it is present, there is a Three measurements go into the directional survey: (1) measured depth, (2) deviation angle, and (3) direction of deviation. 7. The horizontal plane option is not supported by all software. Jan 19, 2022 · A horizontal well is a special type of directional well. Identify the pipe staging and assembly areas. Directional diamond drilling Directional diamond drilling is a special method of drilling into the Earth’s surface in order to explore ore bodies by reaching a specific zone or target and controlling borehole trajectory by special means. 1. Download User Guide. S-Curve. User controls the average deflection used and depth of the bore through the entry and exit portions of the profile, while this calculator does the rest; including determination of whether or not a central horizontal section is required. This section describes why directional drilling is required, the sort of well paths that are used, and the tools and methods employed to drill those wells. As a focused directional drilling technology developer and manufacturer with access to world-leading R&D facilities, we are solely focused on designing, manufacturing, and supporting our directional drilling customers with the tools they need to successfully compete globally. Many factors must be considered in the drill View the latest version of well Plan. Build-up section. It poses multi-objective optimization challenges. Download Average Viewpoint Method Calculations. , can then be done. The drilling of such type will be with the following sequence: First, the wells can be vertically drilled to the kick-off point (shallow depth). Keywords Drilling technology Vertical drilling Directional drilling Deep formations 1 Introduction directional drilling performance than is conveyed in directional vertical section and plan view plots. Tom Inglis. Lapeyrouse, in Formulas and Calculations for Drilling, Production, and Workover (Fourth Edition), 2016. In fact, even in a vertical well, it might be necessary to deviate to avoid a geological formation or a previous stuck pipe, then return to the original path. Closure Distance = √ Y² + X² (i. Sep 24, 2009 · On the other hands, the negative Vertical Section can occur because the difference of angle between VSD and A zavg, (VSD – Az avg), is out of range of +90 to -90 degree AZI. “VS” is the Vertical Section; it is the length of the projection by the Horizontal Suppress (HD) onto the Vertical Section plane defined by its azimuth. Custom. Build hold and drop trajectory Directional wells of this type is quite difficult because not only maintain This Article covers simple drill string design steps for vertical and directional wells. 2 Horizontal Directional Drilling (HDD) Horizontal directional drilling consists of several installation steps. The drill pipe in the curved section from 5600 to 5000 is divided into twelve 50-ft elements because the inclination and azimuth change across the curved section. The Radius is Flection Directional Training Polls Calculation The document discusses different methods for calculating directional drilling surveys, including the tangential method, minimum curvature method, and balanced tangential method. Then, the well is deflected smoothly until a maximum inclination angle with the desired azimuth. Please find the Excel sheet used for directional survey calculation with Radius of Curvature Method. For directional surveying, there are three azimuth reference systems: Jan 1, 1994 · Wells with a medium radius drilling technique change from vertical to horizontal at 8 to 207100 ft with a horizontal length extends 1000 feet or more. A downhole drilling motor consists of a power section, transmission, and lower end, and is usually directly behind the drill bit in the drilling string used in vertical and directional drilling. In everyday drilling, the objective is to stay the course and get the well to total Depth. By DrillingFormulas. This deflected fluid then flows over the blades of a rotor, which causes the drive shaft itself to rotate. 00N 416,695. Some 35 years ago I was somewhat precariously balanced in a drilling derrick aligning a whipstock into a directional hole in North Holland by the Stokenbury method, and no doubt thinking to myself that I was at the very forefront of technology. [1] Dec 16, 2017 · Planning The Oil & Gas Well Trajectory in Directional Drilling. An example calculation is shown for the tangential method, minimum curvature method, and dogleg Sep 12, 2009 · As per the calculation above, North = -49. It has widened the approach of drillers and brought profit to the owners. Apr 22, 2014 · Improved continuous inclination and azimuth near the vertical section also gives the directional driller confidence that the vertical section is truly vertical. True Distance (m) = 1503. This paper undertakes the issue of tubular friction modeling in directional wells and presents a new approach for calculating torque and drag which relies on the beam theory for large Fig-1- Type I Directional Well 2. version: 5. The XYZ coordinates for this program equate to East-West (X), North-South (Y) and True Vertical Depth (Z). A number of survey calculation methods have been used in directional drilling. Below are listed few of the basic terminologies commonly used in directional drilling-. Download Free PDF View PDF. The Directional Drilling Survey provides the control of directional drilling of oil wells with calculations and plotting of well planning and survey data in vertical section, plan and x-y-z views, calculations between two survey stations, easy tools to 2D and 3D wells and plot multilateral wells. - Calculation of Departure (DEP3) the calculation is intended to find out how far a target of drilling the initial position. 14. It equips the operator with a superior mechanism with which to monitor the progress of directional control as a well is drilled. E/W rectangular coordinates on horizontal plot). 608. This article provides a calculation of the profile, which, at a given radius of curvature, ensures the required zenith angle of multilateral wells of a horizontally branched section at the required depth, the lengths and projections of other characteristic profile sections, the coordinates of the end points of the branches and the values of the zenith angle and azimuth in them when drilling Jul 1, 2022 · Multimodal objective function is figure out by optimization algorithm. Drilling and Completion Calculations. Directional drilling (or slant drilling) is the practice of drilling non-vertical wells by deviating a wellbore along a planned path to a target located a given lateral distance and direction from vertical. The dogleg angle equation presented in the Minimum 3 Curvature section of the API Bulletin D20 was obtained from Blythe11. E/W rectangular coordinates on the horizontal plot). to indicate to drilling personnel that the motor may be damaged. These measurements, taken at specific depth intervals, are used to calculate the directional survey of a well. TVD = 62. . The technique of measurement of these three components is termed a survey. Jun 29, 2015 · The measurements are used together to calculate the 3D coordinates, which can then be presented as a table of numbers called a survey report. 66 + 398. txt) or read online for free. The purpose of this program is to provide a user-friendly trajectory design interface for the unique requirements of the HDD (Hydraulic Directional Drilling), industry to plan drilling trajectories starting and ending at any inclination and with multiple Tangent and Curve (Bend) sections. Vertical Section. Include safety data sheets for the identified drilling fluid components and additives. 30 (entry point) to the exit point following the geometry of the Fundamental Concepts and Basis of Directional Drilling For any directional drilling, three components are measured at any given point in the wellbore in order to determine its position. Directional Drilling Survey Calculations - Free download as PDF File (. Then, calculate the depths and distances of any directional changes and wells or perforations. May 2, 2023 · When drilling a tangent or hold section with NDS, the following should be observed: After observing NDS directional tendencies over a minimum of 200 ft of rotary drilled interval, a plan for drilling long distances between orientations should be established. Introduction. Horizontal directional drilling (HDD) is used to drill cavities through geomaterials at relatively shallow depths. This plan should minimize the number of orientation toolsets and maximize penetration rate. Although it is possible to hit small targets, this increase in accuracy comes with a higher Oct 30, 2017 · ∆Vertical Section = CANDLE x cos ( B – target direction) Places: A = (I 1 +I 2)/2; BORON = (A 1 +A 2)/2; Download The Directional Drilling Survey Calculation Excel Spreadsheet For Average Angle Method & Terminology From Below. Well profile = J-profile (build and hold) The surface location coordinate of Well-A is 6,543,065. 66 ft. This can be achieved through a perfect combination of well design 2. Slant-well, S-shape, and maximum turn well paths can be computed. Finally, use the desired calculation method to calculate the vertical section. Az1= Azimuth direction at upper survey. Therefore, the surface and the target for Well-A can be illustrated is The Minimum Curvature Method is used to calculate 3 dimentional Boreholes based upon X,Y,Z displacements for each section. Directional drilling animation. 216. Measured in: degree. This paper describes a radius-of-curvature calculation of the three-dimensional (3D) path of a directionally drilled well from kickoff point to target. Ref book: Formulas and Calculations for Drilling, Production and Workover, Second Edition. Directional drilling is defined as the practice of controlling the direction and deviation of a wellbore to a predetermined underground target or location. It is therefore a key calculation variable and not merely a reporting option. The major reasons for horizontal drilling are Intersecting many vertical fractures in a single wellbore; Increasing production rate in low permeability formations; Reducing water and gas Nov 11, 2013 · Directional Drilling. 1. 00E and the target is located at 6,542,213. Aforementioned distance is B3B2. Equations are developed for calculating critical points along the well path in terms of cartesian coordinates and directional survey parameters. 3 Noteworthy papers in OnePetro. East = 50. The length of the hypotenuse of a right angled triangle, with two sides of length x and y (square root of x2 + y2). V. The five most commonly used are: tangential, balanced tangential, average angle, curvature radius, and minimum curvature (most accurate). Engineering Consulting. e. 671 ÷ 0. Inclination is the measurement of angle (in degrees) between true vertical (local gravity vector) and the well bore axis at any given point. After the tangent section, a drop-off section is drilled where the inclination is reduced and the well path is almost vertical as it hits the May 3, 2018 · Turbine Motors work by harnessing the energy of a continuous flow of steam which passes through them. Choice of Vertical Section Azimuth • The vertical section azimuth is typically chosen to give the most useful view of the wellpath on the section view of the drilling plot • For a 2D wellplan, the vertical section azimuth will usually be the direction of a straight line drawn from the slot to the end of the wellpath • This gives the most Apr 5, 2017 · Abstract. Well-design optimization models initially focus on wellbore-length minimization, but ideally also need to consider minimizing the surface torque during drilling and address, among other constraints The directional Casing Drilling system has been used with 5-1/2”, 7”, 9-5/8”, and 13-3/8” casing to drill deviated wells with relatively low inclinations. The target in this case is an area, rather than a single point, and the well need not therefore hit the center of the target. The well is kept vertical until KOP and an inclination is built and the tangent section is drilled. 1 Introduction and Purpose. Springer Science & Business Media, Nov 11, 2013 - Science - 260 pages. Right all Directional Drilling Survey Calculation Methods & technical & downloads radius is understanding is essential to all concerned with directional drilling for both proper application of directional drilling equations and selection of a method which best describes a particular wellbore. View the video. All The aim of this paper is to focus on some basic terms definitions and simple practical calculations. 2 Build, hold and drop profile (S Type) It also called shaped wells. Mar 8, 2024 · Place the drill bit on the center point of the marked radius on the pipe. Then, you can make projections for the target, others. 5 Dropping assemblies: pendulum principle. Design steps to reduce fatigue damage are also covered. The basic sequence of steps of an HDD installation consists in a preliminary design, followed by the drilling of a pilot bore from the drilling rig. Projections to the target, etc. Aug 14, 2018 · Directional drilling is a broad term used to describe any boring that doesn’t go in a straight line vertically down. The mathematical trajectory planning calculations and equations are the same as those used in directional calculations presented by Azar and Samuel,1 Mitchell,2 Bourgoyn,3 Hossain and Al-Majed,4 Rabia,5 and Mitchell and Miska. Apr 26, 2017 · ISBN 978-1-55563-114-7. Oct 31, 2017 · Each size and type of PDM is designed to take a certain range of fluid volumes. Feb 6, 2024 · Once you have all of this information, you can calculate the vertical section in drilling by first identifying the start and end depth of the section. Efficiency improved Figure 3: During field-testing in the Eagle Ford, the RSS continuous azimuth matched the MWD static surveys taken every 100 ft along the lateral section. First, a pilot bore is made with a suitable-sized drilling rig. Directional Drilling Books Jun 26, 2015 · Directional drilling. 26 pounds per square inch of hydrostatic head pressure on a formation at a depth of 30 feet, while a vertical drilling fluid of the same density will exert 110 pounds per square inch of hydrostatic head on a formation at a depth of 250 feet. Orients deflection tooling for navigating well paths. In this case, the total TVD would be 79. Apr 27, 2019 · Current through April 27, 2019. Applications for this program include civil Directional Drilling for Mac OS X. Oct 30, 2017 · The distances between other wells and the proposal are calculated frequently in the critical section. The following data is calculated with a minimum of end point entries. The system has also been used with 7” and 5-1/2” casing to drill several test wells with inclinations that approached or exceeded horizontal. The shape of the well could be vertical or directional. Successive reamers are then pulled back to enlarge the bore diameter to the desired Jan 17, 2018 · Kick off depth = 4,200’MD/4,200’TVD. More specifically, drilling fluid travelling down the drillstem is deflected by the blades of a stator which is connected to the housing. Finally, a brief summary and prospect of vertical and directional drilling are presented. 00E and the UTM zone is 31N. 01 Scope of Work The work specified in this section consists of furnishing and installing underground utilities using the horizontal directional drilling (HDD) method of installation for pipes of various sizes, also commonly referred to as directional boring or guided horizontal boring. Formulas for calculating north, east, true vertical depth, ratio factor, and dogleg severity are provided for each method. I1 = inclination (angle) at upper survey in degrees. Well Plan is a fully integrated Directional Drilling program for Vertical,Slant,Horizontal, S-Curve or Similar research by Sperry, a gyrocompass 2 manufacturer, and Sun Oil Company lead to Sperry-Sun Drilling Services, both Eastman and Sperry names live on as directional drilling subdivisions of major Oil industry service companies. Basically it refers to drilling in a non-vertical direction. 29. time the hold is so that drilling can be calculated carefully so that the cost involved can be minimized. Sec (Vertical Section) Vertical Section is calculated using the following equations: Closure Azimuth = ArcTAN [ ] Azimuth Difference = Closure Azimuth - Vertical Section Azimuth. 144 x 3. There are several known methods of computing directional survey. 144 m. 2017 • Roman Raspopov. You may also be interested in: Drilling Software. Oct 30, 2017 · Only then, plot the latest bottom-hole coordinates on to directional well plot (TVD vs. True Distance (ft) = 1504. The well trajectory influences many factors, such as wellbore stability, mud transport, fluid flow, and Jan 1, 2020 · Inglis (1987) presented the directional drilling calculation methodologies. Then, it is preferred to run casing if Jan 7, 2017 · Contents. Keeping the well vertical is one of the most challenging tasks [2]. 2 References. 156 DIRECTIONAL DRILLING CALCULATION TECHNIQUES The more common methods that have been adopted are described in the following paragraphs. D. Jun 13, 2021 · About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How YouTube works Test new features NFL Sunday Ticket Press Copyright Apr 11, 2020 · Optimizing the trajectory of directional wellbores is essential to minimize drilling costs and the impacts of potential drilling problems. The aim of the present overview is to review and discuss the vertical and directional Jun 29, 2015 · Calculation methods for directional survey. The effect of right-hand The vertical line is always parallel to the direction of earth's gravity. 34. 3 m) to have wellbore geometry from vertical to horizontal in 20 to 60 ft. The depth, drift angle (inclination) and azimuth are measured (Osisanya, 2009). 1 Definitions of Directional Drilling Directional drilling is defined as the deflection of a wellbore in order Jun 1, 1981 · Summary. pdf), Text File (. Horizontal. Mar 18, 2023 · Shallow KOP. Where Y Dec 8, 2020 · The predetermined trajectory of the 2D directional well generally includes four types of well sections: the vertical section, the build section, the hold section, and the drop section. Target Data is included for up to four targets. 281. The Purpose Directional Drilling Survey Calculations. True Distance (m) = Map Distance ÷ scale factor. The directional drilling trajectories software is programmed, and the optimum trajectory for directional drilling is designed. Figure 3-17 shows a portion of the directional survey from a deviated well. In this instance, the driller uses sidetracking techniques. Inclination and azimuth will be represented by a and /3 respectively, with the subscript 1 denoting the upper station and 2 denoting the lower station. Purpose of directional survey. 1 Factors that determine drilling tendency of the bottom hole assembly (BHA) 1. Wells with a short radius systems, in comparison, change angle at 1. The motor should be tripped out immediately without over-pull or string rotation to improve the chances of successfully tripping out the entire motor. Apply gentle pressure and start drilling into the pipe. 2 Deviation/Departure Calculation. Aug 16, 2018 · Directional Drilling is the process of directing a wellbore along some trajectory to a predetermined target. Sep 8, 2009 · Facebook 0 Tweet 0 Pin 0 LinkedIn 0. The bore is steered to create an initial hole at the required line and grade. Download a Free Trial. Wells with an inclination greater than 60° are referred to as highly deviated wells. These anti-collision calculations in directional drilling operations & travelling cylinder plots can be performed using the applications COMPASS or WELLPLAN. The hole total TVD usually remains the same as the TVD of the well at the start of the horizontal section. me ms fy zy ht ne bk ib ot rf