Once properly commissioned and tested the Mud Cap Drilling system, drilling can be done the conventional mode until actual circulation losses conditions dictate to switch to Mud Cap Drilling mode. At…
Wells may require sidetracking in order to re-drill the well to a new target, sidetrack past a fish or sidetrack due to hole problems.
The main requirements in sidetracking a well is the development…
Sidetracking out of Casing with Whipstock
The ‘Window Master’ whipstock is a one trip system to mill afull size hole in casing in the required direction. The whipstock is mechanically set and requires a bridge plug to be set at a suitable…
This article presents the main conversion factors for oil field and SI units.
Length/Depth/Distance (SI unit - m)
This article describes the various depth references used for drilling onshore and offshore wells: Reference Datum, Chart Datum (CD), Mean Sea Level (MSL), High Tide (HT), Low Tide (LT), Water Level…
1. Programme Summary
This programme will prepare the existing well for a forthcoming horizontal side-track which is due to begin immediately upon the successful completion of the…
1. Rig move preparation
- Location survey
- Road Survey
- Preparation of advanced loads
- Administration (Rig move plan)
- Equipment Inspection
2. Preparation of new location and camp
1. Conductors at jacket level
This article describes the standards for Drillpipe and Bottom Hole Assembly (BHA).
Pipe Tally Requirements
Master Drillpipe Tally Book
- The master drill pipe tally book shall be kept by the Driller in…
- Ensure that a drill pipe strainer is ALWAYS in the pipe when pumping fluids into the well
- Ensure 4 x ditch magnets are in place for extracting milled cuttings.
- Prepare sweeps prior to milling…
This article describes the keys elements for preparing a HPHT procedure
An offshore Daily Meeting will be held between Company Drilling Supervisor, and service companies to review programme, procedure…
The Superintendent or Senior Operations Engineer shall conduct a pre-spud meeting on the rig with all relevant personnel directly or indirectly involved with the operations.
The appropriate Drilling…
The causes of tight holes include: Insufficient inhibition, Mud weight, Lubricity and Hole cleaning.
All these factors are important and comparisons should be made between wells with and without…
General Safety Procedure for Rig Moves
Prior to moving the rig the Drilling Contractor shall address the following points:
- Wearing personal protective equipment is a must when walking around on…
Shallow Draft Jack-Up is one of the rig design concepts for offshore drilling in shallow water environments.
1. Water depth range: 5 – 100m. Shallow water capability from fully retracting spud…
The existence of substantial vibrations in the drillstring have caused much trouble time during drilling in slim (and conventional) holes. Minimising drillstring vibrations during the drilling of slim…
Jacket Supported Offshore Rig is one of the rig design concepts for shallow water environments.
- Steel Jacket can be tailored to water depth.
- Rig design is independent of water depth.
1. Rig move preparation
- Administration (Rig move plan)
- Equipment Inspection
2. Preparation of new location
- Hydrographic surveys
- Diving/seabed surveys
- Preparation of…
Well and rig summary information plus the date that the well was spudded and abandoned / suspended / handed over to Production.
Well schematic showing final well status.
Land rig on barge (with optional submerged caissons) is one of the drilling rig design concepts for offshore shallow water depth environments.
- Barges are a proven concept in shallow water and can…
Cantilever Drilling Barge is one of the rig design concepts for shallow water environments.
- Water depth range: 3 – 7m
- Low environmental impact
- Suitable for ice. This is a development of the…
Standard Jack-Up is one of the rig design concepts for offshore driling in shallow water environments.
1. Water depth range 10 to 120 m for standard Jack-ups
Minimum draft for small jack-up is…
Submersible driling rig is one of the drilling rig design concepts for offshore shallow water environments.
1. Could operate in water depth of 3 to 30 m.
2. Environmental Impact Potentially…
This article describes the Stand-by vessel (SBV) and Fast Rescue Craft (FRC) duties, equipment and standards
The Master of the stand-by vessel shall ensure that:
- Portable radio sets and…
The Mud Cap Drilling (MPD, Managed Pressure Drilling) is a technique that can be used even in case of total circulation losses.
Circulation losses are traditionally cured with Loss Circulation…
Some of the standard drilling tools commonly used in drilling are briefly described here, together with procedures for, and information on, their use. More detailed descriptions and specifications of…
This article describes the basic Drilling Standards.
The Drilling Department shall deliver a ‘fit for purpose’ wellbore, the criteria of which are:
- attainment of the required bottom hole position
The information contained in this document is provided as guidelines and should be used in conjunction with the kick procedures flowcharts to deal with specific well control problems.
The main requirement in sidetracking a well is the development of a lateral force to allow the bit to cut on the side of the hole.
The required lateral force shall be provided by the…
This article describes the specifications and inspection requirements of the various BHA components for horizontal wells.
- All BHA components should have received a full…
On a monthly basis the Drilling Contractor shall be provided with a list of proposed new locations. This list is initiated by Drilling Manager and includes buffer locations to allow for…
Drill 8 1/2" hole to 15316 ft, run a lookahead VSP, drill 8 1/2" hole to ± 15581 ft (85 ft above the "x" marker, run logs and set the 7" liner .
1. The actual depth of the liner…
Steel Caisson and Drilling rig
Drilling rig on a Steel Caisson is one of the drilling rig design concepts for offshore shallow water environments.
1. Water depth range: 5 – 100m however must be designed for a limited water depth…
The Ingram Cactus Exact 15 Universal Slim-hole Drilling and Completion System was specifically developed for use with slim-hole casing designs suitable for installation through small bore BOP stacks…
Drilling Rig on Pre-Installed Piles and Modules is one of the drilling rig design concepts for shallow water environments.
1. Water depth range: 0 – 3 m.
2. Low environment impact
This article presents examples of loadout/ equipment list for the following hole section: 36", 26", 17.5", 12.25", 8.5" and 6"
Posted Barge With Land Or Modular Rig is one of the rig design concepts for shallow water environments.
1. Could operate in water depth of 1 to 10 m.
2. Environmental Impact Potentially low.
Semi-Submersible is one of the drilling rig design concepts for offshore shallow water environments.
1. Water depth range: 30 – 1000m
2. Environmental Impact low
3. Not suitable for ice
Heli-Rig is one of the rig design concepts for shallow water environments.
1. Independent of water depth. Requires a support structure which in itself would not be helicopter transportable,…
Types of vessels, offshore operations, supply vessel, stand-by vessel, AST vessel
- Specifications may vary from above, and capacities are approximate only.
- Fuel consumption figures are given as a…
Land rig on artificial island is one of the drilling rig concepts for offshore drilling in shallow water environments.
1. Water depth range: 0-10m. Costs rise significantly with water…
Responsibilities for preparation, approval and content of the drilling programme.
Drilling Programmes are the approved instructions for carrying out activities and tasks which are required to achieve…
The following table lists those problems commonly encountered in drilling extended reach (ERD) and horizontal wells and recommendd precautions.
Inefficient Hole Cleaning & Reduced Borehole…
Mechanisms of rock cutting
Bits and coreheads cut rock by crushing, shearing, grinding or jetting. Crushing bits are the well known roller cone bits and hammer bits.
1 Crushing bits - roller cone rock bits
Crushing bits work by…
Modularised and Pile Elevated Drilling Rig is one of the drilling rig design concepts for shallow water environments.
1. Water depth range: 2 – 10m
2. Low environment impact. Installation and…
Every offshore drilling operation must include some possibility of underwater intervention. This may be required for a variety of routine tasks including re-entry, guide-wire or riser connection,…
This article describes the various issues to be considered for planning an offshore rig move.
1. Well/Jacket Status
Well Plugging Prior to Rig Move
- If the current well path is less than 100 ft from…
Rig moves should be carried out by two Marine Personnel. Deviations from this rule can only be authorised by the Marine Manager. The Marine Manager, or his nominated deputy, shall supervise the actual…
After completion of the drilling operation by the drilling rig, the well is suspended.
The following possibilities exist:
- The well will be re-entered within a short period by the work over rig to…
Offshore Rig Moves Planning and Preparation
The Marine Officer should plan the courses between locations, and routes to be taken through fields with due regard for jackets and barges or other vessels which may be moored in…
For an area where no previous knowledge of jack-up penetration / sub-bottom information is available the location must be cored, this may be done by a coring vessel prior to rig arrival or from the…
Lost Circulation is not always a major problem; however, the procedure below should be followed when losses do occur:
1. Check surface equipment for leaks. If this fails to show any signs of leakage,…
The purpose of this outline program is to set the framework for the operations.
This programme will prepare the existing well, for a forthcoming near horizontal multilateral side-track…
Sequence of Operations - Typical Onshore Well
This article describes the sequence of operations and the general practices for a typical onshore well.
1. Prepare access road and well lease
The following techniques should be used while drilling Unconsolidated Formations:
1. Obtain maximum annular velocities by using critical velocity circulating rates.
2. Use a "Clayball Trap" or a small…
The objective of abandonment is to prevent the migration of all formation fluids, but especially hydrocarbons, between formations and to the surface. There are two types of conduit which must be…
The following information should be included in the daily rig move report to be submitted to Superintendent.
Onshore Rig Move
- Old location
- New location
- Total loads
- Loads moves
- % Rigged up
AH Along hole
Pre-Spud Drilling Equipment Suface and downhole Inspections
Prior to commencement of each well the Drilling Supervisor with the assistance of the Drilling Contractor Toolpusher shall perform a full rig inspection and record the results on the Company Drilling…
When moving into a new location the following hydrographic surveys are required:
- sidescan sonar
- water depth
- soil analysis.
These surveys are by arranged by…
This article describes the various ways of transmitting mechanical power to the bit by rotation. There must be sufficient HHP at the bit to keep the cutters or diamonds clean, and that an…
The documentation listed below must be available at the rig site prior to commencing the operations:
- Concurrent Drilling Completions and Production Operations (if applicable)
- Emergency Response…
Drilling fluid volumes (active, reserve and kill mud)
The minimum safety stock of mud available on surface prior to and whilst drilling any potential high pressure formation will be:
Main features of the MC2 compact wellhead are described below:
- Flow through casing hanger with 45 degree shoulders and centralisation feature.
- "Fastlock" hub and metal/metal "CX" gasket on wellhead…
Underreaming procedures vary from tool to tool. However, it shall be verified that:
- the tool is function tested with the mud pumps on surface before running in
- the cutters are secured inside the tool…
Responsibilities for the implementation, supervision, verification and control of rig moves and site work are listed in the following table:
This article describe the well status requirements for Onshore Rig Moves.
1. Well Status Prior to Rig Move from Old Location
The following barriers shall be in place in a development well:
Rig Move Inspection Requirements (Onshore Operations)
Drilling Contractor Inspection Requirements
Prior to and during any rig equipment movement, the Drilling Contractor shall make inspections and checks on crane and support equipment condition eg.,…
- Kick-off and Initial Build Section
- Responsibilities during drilling operations
- Mud cooler for HPHT wells
- Data Recording for Horizontal and ERD wells
- Bit Selection and Hydraulics
- Truck Driver Rig Move Toolbox Meeting
- Surveying requirement for exploration well
- Well Planning Information Sheet
- Responsibilities for Abandonment
- Emergency Response Responsibiliites
- Baryte plugs to cure losses
- How to avoid Hole Related Problems
- Abandonment programme - oil producer