Introduction to Well Completions Agenda At the end of this presentation, you will be able to: Define completion Factors influencing completion design. List and define the different types of completion Describe surface control equipments Define subsea completion M 4: Completion D 01: Module Objectives Audio Narration: In this module, you will learn about the steps in the process of completion in oil drilling, the equipments used, and about surface control equipments. At the end of this module, you will be able to: Define completion Describe the process of completion List and define the different types of completion Describe surface control equipments Define subsea completion Note to GD: Bullets in sync with VO. RECREATE Image: show diagram of an oil well

Completion Completion Process 30’’ CASING 20’’ CASING 13 3/8’’ CASING 7’’ LINER RESERVOIR SEA BED PLATFORM Production casing (9 5/8) Downhole Equipment Safety Equipment After exploratory drilling confirms the presence of an oil or natural gas reservoir, the hydrocarbons are brought to the surface. Once the design well depth is reached, the formation is tested and evaluated to determine whether the well is to be completed for production, or plugged and abandoned. This decision is taken based on the information available on reservoir characteristics. To complete the well production, casing is installed and cemented, and the drilling rig is dismantled and moved to the next site. A service rig is brought in to perforate the production casing and run production tubing along with down hole equipments. The installation of surface safety equipments takes place and production begins. M 4: Completion T 01: Completion Process D 01: Introduction Audio Narration: After drilling has confirmed the presence of an oil or natural gas reservoir, the hydrocarbons are brought to the surface. Once the design well depth is reached, the formation must be tested and evaluated to determine whether the well will be completed for production, or plugged and abandoned. This decision is taken on the information available on reservoir characteristics, such as the size of the reservoir, the porosity and permeability of the reservoir rock, and the amount of natural energy or reservoir pressure, within the reservoir. To complete the well production, casing is installed and cemented and the drilling rig is dismantled and moved to the next site. A service rig is brought in to perforate the production casing and run production tubing along with downhole equipments. If no further pre-production servicing is needed, the surface safety equipments, such as the Christmas tree are installed, and production begins. Completion Process

Completion What is Completion? Completion Process It’s a link between drilling the borehole and the production phase. Well completion creates a dependable pathway to the surface for the hydrocarbons. Once the well is drilled, it has to be made ready for the safe and efficient production of oil. The term ‘completion’ describes the assembly of Down hole tubulars and other safety equipments that is required to enable the safe and efficient production of oil or gas from the well after it has been drilled. M 4: Completion Topic 1: Completion D 02: What is Completion? Audio Narration: Once a natural gas or oil well is drilled, and it has been verified that commercially viable quantities of natural gas are present for extraction, the well must be 'completed' to allow for the flow of petroleum or natural gas out of the formation and up to the surface. Well completion creates a dependable pathway to the surface for the hydrocarbons. Once the well is drilled, it has to be made ready for the safe and efficient production of oil. Completion refers to the assembly of downhole tubulars and other safety equipments that is required to enable the safe and efficient production of oil or gas from the well after it has been drilled. Note to GD: Show the oil well. Let the labels appear one after another. Completion Process

FACTORS INFLUENCING COMPLETIONS DESIGN. Purpose of the well The environment Drilling The reservoir Production Completion techniques

Purpose of the well Exploration wells: To obtain preliminary data on a reservoir, nature and characteristics of the fluids on the reservoir, pay zone characteristics (pressure, temperature, permeability and productivity) Appraisal or confirmation: Refine or complete the data from exploration and determine the off-wellbore characteristics (permeability, reservoir boundaries, existence of faults/discontinuity) Developmental well: This stage brings the wells on the production stream. Assess well conditions and effectiveness of completions and obtain further info on the well. Production- productivity Injection- Optimize reservoir pressure Observation-monitor variations in reservoir parameters

Parameters related to the Environment Constrains related to country/site/location of well i.e land or offshore. Environmental restrictions involve: Difficulty in obtaining supplies Available space Available utilities Safety rules and regulations Certain operations that may or may not be possible Meteorological and oceanographic conditions must also be taken into consideration where applicable.

Parameters related to the Drilling Types of rigs (drilling/completions) Well profile- horizontal/directional Drilling and casing program Drilling in the pay zone(s) and drilling fluids- formation damage and fluid contamination. Cementing the production casing Drilling and casing program- have a borehole big enough to accommodate the equipment that will be installed in it. In contrast, if the diameter of the pay zone is is increased beyond what is required by the production equipment, it does not boost the well flow capacity very much. The inside diameter is effectively usable in the well once all the drilling and casing phases have been concluded.

Parameters related to the Reservoir Reservoir pressure and its changes- need for injection wells? Interface between fluids and their changes- water encroachment Number of levels to be produced Rock characteristics and fluid types Production profile and the number of wells required.

Parameters related to the Production Safety- compliance with various regulations Flowing well or artificial lift- a wells flow capability depends on natural changes in bottom hole pressure versus cumulative production. Operating conditions- space availability, operating fluids-erosion/corrosion Anticipated measurement, maintenance or work over operations- maintenance and repair operations to ensure the well reaches its lifetime

Other factors Parameters related to completion techniques: general configuration, pay zone to bore hole connection, treatment of the formation, equipment installed, artificial lift Synthesis-How completion is designed- completions should be designed to optimize productivity/injectivity performance, make sure the well produces reliably and safely, optimize the implemantation of atrificial lift, optimize equipment lifetime and make it easy o change all or some of the equipment in the future without much difficulty.