The heart of a conventional gyroscope is the gyro wheel, which spins at high speed symmetrically about an axis. A perfect gyro wheel will maintain its orientation in inertial space for as long as no external forces act on it to alter the direction of the spin axis. In conventional gyro directional survey tools this … Conventional Gyroscopic Survey Tools

Desription of typical North Seeking gyro:  Seeker (Baker Hughes Inteq), Wellbore surveyor (gyro/data), Finder (SDI), GCT (Schlumberger ), G2 (Sperry-Sun) Seeker (Baker Hughes Inteq) 1 directional drilling survey tool description The Seeker from Baker Hughes Inteq is a single axis gyro tool, i.e. the gyro has one sensing axis in the cross-borehole plane. As stated … North Seeking gyro – Common tools description

North Seeking gyro directional drilling survey tools provide substantially more accurate survey data than conventional gyro tools. In the conventional gyroscopic survey tool, the gyro is oriented to a known reference direction or foresight. A North Seeking gyro directional drilling survey tool uses a gyro to reference itself to True North, eliminating the need for … North seeking gyro survey tools

This article describes the data required for a survey program and report. 1 General well data ·well name / ·wellhead co-ordinates (North, East, TVD, latitude and longitude) / ·co-ordinate reference (grid, true or magnetic North, type of grid system) / ·grid convergence and definition (in wording and drawing) / ·declination and definition (in wording and … Survey program and report

Surveying Responsibilities: 1. Drilling manager: – anti-collision strategy is in place; – blow-out contingency plan is available to ensure that as soon as there is a potential or actual blow-out at any time during the life of a well, the planning of a relief well and the decision on its surface location can be made … Surveying Responsibilities

Definitions of various surveying terms: Survey A series of measurements made to determine the borehole trajectory. A survey comprises position (North, East and True Vertical Depth) and/or direction (along-hole depth, inclination and azimuth) from which position is calculated. Survey tool accuracy The potential of a survey tool to determine the actual borehole position. The borehole … Surveying definitions

The survey accuracy requirements are dictated by the following: 1. Targets The geological target should be as large as possible to minimize costs (directional drilling and surveying), considering the expected survey uncertainties. 2. Collision avoidance The survey accuracy is defined by the separation factor (SF): the ratio between the 3D centre to centre well distance … Survey policy

An initial kick-off and build section with smooth build rates is required to minimise torque and drag in deeper critical hole sections. The Drilling Supervisor should ensure all personnel are aware of this requirement and that potentially troublesome doglegs are wiped immediately. Doglegs and Decreasing Build Rates Excessive doglegs or a drop in build rate … Kick-off and Initial Build Section

This article describes the specifications and inspection requirements of the various BHA components for horizontal wells. Inspections requirements All BHA components should have received a full inspection prior to use on an extended reach well. Stress relief grooves are required on all components (including non magnetic components and jars). The complete BHA should be returned … BHA Components and Inspections

The following directional surveying standard are recommended: All exploration wells shall be surveyed from the surface conductor shoe to TD All development wells shall be surveyed from the wellhead to at least the lowest hydrocarbon bearing zone Survey tool selection for definitive surveys shall be based on the anti-collision requirements, survey tool accuracy, target size … Directional Surveying Standards