1- Introduction To Completion

Introduction To Complétion

Completion : Definition Definition The word “ Completion “ it self means conclusion, and more particulary in the case we are concerned with the conclusion of a borehole that has just been drilled. Completion therefore the link between drilling the borehole as such and the production phase. Completions are the interface between the reservoir and surface production Completion involves all of the operation designed to make the well Produce/Inject, in particular connecting the borehole and the pay zone, treating the pay zone, equipping the well, putting it on stream and assessing it. By pay zone we mean a zone consisting of reservoir rocks which contain Oil &/or Gas that can be recovered The role of the completion designer is to take a well that has been drilled and convert it into a safe and efficient production or injection conduit.

Completion : Definition Completion enginner

Completion : Definition Objectives of Completion: • • • •

Provide optimum flow conditions. Protect casing. Down hole emergency isolation. Permit down hole chemical injection. • Permit down hole measurements. • Isolate producing zones

Completion : Definition The main factors influencing completion design: There are many factors influencing completion, six types of parameters are related to • • • • • •

The Well’s purpose The Enviroment Drilling The Reservoir Production Completion technique

Completion : Definition The well’s purpose: The purpose drilling can vary depending on the well, with a distinction basically made between • • •

An exploration well An appraisal or confirmation well A developpement well

Related to environment: • • • •

Difficulties in obtaining supplies Constaint on operation due to well site location Meteorological /Oceanic conditions Safety rules

Completion : Definition Drilling: • • • • •

Type of drilling used : caracteristic, rig equipements.. Well profiles : horizontal, deviated wells… Drilling and Casing program: Diametre : Drifting Pay zone and drilling fluids Cementing the production casing: quality of cementation

Reservoir: • • • • •

Reservoir pressure: Pres =f (Q, t, …) Fluides interface : oil/water contact , coning, %oil … Nbres of producing level Rock caracteristics and fluid type: nature of rock, fluid viscosity, reservoir damage, corrosive fluides, scale… Reservoir Caracteristics : size, permeability barriers, drive mecanism, well drainage radius…

Completion : Definition Production: • • • •

Nature of flowing / Artificial lifting Operating Conditions Anticipating maintenance and work overs operation Safety: nbers and type of completion equipements…

Completion techniques: • • • • • • •

Generale configuration The pay zone to borehole connection Treatement of the formation if required Different pieces of well equipement installed Operating procedure used to carry out completion Possible artifiacial lift Procedure for work on the well …

Completion : Definition

Completion : Definition Completion design criteria: •

Profitability: provides production optimization and maximize operating cost over its life

•

Fexibility: for handling the current and future problems

•

Simplicity: to allow the most efficient installations aand maintenance activities

Types of Completion Types of completion : Wells can be producers or injectors. Completions can produce oil, gas and water. Completions can inject hydrocarbon gas, water, steam and waste products such as carbon dioxide, sulphur, hydrogen sulphide, etc. More than one purpose can be combined either simultaneously (e.g. produce the tubing and inject down the annulus)or sequentially (produce hydrocarbons and then convert to water injection duty). Completions are often divided into the reservoir completion (the connection between the reservoir and the well) and the upper completion (conduit from reservoir completion to surface facilities).

Types of Completion Reservoir completion : Major decisions in the reservoir completion are:

• • • • •

Well trajectory and inclination Open hole versus cased hole Sand control requirement and type of sand control Stimulation (proppant or acid)/Fracturation Single or multi-zone (commingled or selective)

Types of Completion

Types of Completion Upper completion methods : Major decisions in the upper completion are :

• • • •

Artificial lift and type (gas lift, electrical pump, etc.) Tubing size Single or dual completion Tubing isolation or not (packer or equivalent)

Types of Completion

Types of Completion In General: Completion are in 3 class :

• Open Hole Completion • Cased Perforated Completion • Multiple Zone Completion

The use of any type of completion depends on the characteristics and location of the hydrocarbon formation.

Types of Completion Open Hole Completion : Open hole completions are the most basic type and are used in formations that are unlikely to cave in. An open hole completion consists of simply running the casing directly down into the formation, leaving the end of the piping open without any other protective filter. This designation refers to a range of completions where no casing or liner is cemented in place across the production zone. In competent formations, the zone might be left entirely bare, but some sort of sand-control and/or flow-control means are usually incorporated. Popular to be used in case of Horizontal Drilling where cemented installations are more expensive and technically more difficult.

Types of Completion Open Hole Completion :

Types of Completion Cased Hole perforated Completion : It consists of production casing Or Liner casing being run through the formation. The sides of this casing are perforated, with tiny holes along the sides facing the formation, which allows for the flow of hydrocarbons into the well hole, but still provides a suitable amount of support and protection for the well hole. The process of perforating the casing involves the use of specialized equipment designed to make tiny holes through the casing, cementing, and any other barrier between the formation and the open well.

Types of Completion Cased Hole perforated Completion :

Types of Completion Multiple zones Completion : It is the practice of completing a well so that hydrocarbons from two or more formations may be produced simultaneously or separately.

Types of Completion Multiple zones Completion :