Assignment- 01
PETROLEUM ENGINEERING
NAME: FATIMA BABAR
CLASS: BS-7A (GEOPHYSICS)
SUBMITTED TO: ANEES UL RASOOL
DATE: 4-12-2020
TABLE OF CONTENT
S.NO TOPIC PAGE
NO.
01 Abstract 02
02 Well design 02
03 The design process 02-06
04 Well selection 03
05 Data collection 03
06 Drilling hazards 03
07 Drill stem test 03
08 Casing 03
09 Cementing 03-04
10 Well head and X-mas tree 04
11 Estimation of items 04
12 Time and cost estimation 05
13 Equipments 05-06
14 Starting date 06
15 Conclusion 06
16 References 06
1
ABSTRACT
Well designing consists of those characteristics which connect the reservoir to the surface so that
fluids can be produced from or injected into the reservoir, provide a conduit for well stimulation
treatments, isolate the producing reservoir from other zones, protect the integrity of the reservoir
especially in unconsolidated formations, provide a conduit to measure the changes in flow rate and
pressure needed to run a well test.
The wellbore provides the only path from the surface to the reservoir. To a large extent, the
successful production and depletion of a reservoir depends upon the successful completion and
workover operations applied to a well. The production engineer designs and supervises all
completion and workover operations.
Main steps for well designing are discussed in this article. Firstly, well selection is done than past
data is collected. After that drill stem test is done to know the structures overlying on reservoir,
condition of reservoir. Casing is done and then cementing to prevent casing from collapsing.
Estimation of items, time and cost estimation, equipments are ordered and then finally starting date
is approved.
WELL DESIGN
Well objectives identify drilling objectives such as well depth, hole size, direction. In order to
achieve well objectives drilling team construct well design, which incorporates casing design,
drilling fluids, bit and tool selection, and drilling technique to manage drilling hazards.
Drilling helps us to know the geological structures that overlay the formation targets, these
geological structures provide drilling hazards in the form of shallow gas, unconsolidated sand, loss
of circulation or overpressure zones, and sections of hard impervious rock.
THE DESIGN PROCESS
Well head and
Well selection Cementing
x-mas tree
Data Estimation of
Casing Starting date
Collection items
Drilling Time and cost
Drill stem test Equipments
Hazards estimation
2
1. Well Selection:
Selection of well is important because well can be wildcat, producing, developed or exploratory
which have different well designing, cost and different safety measurements.
2. Data Collection:
Collection of data is essential for well design, data can be: WELL surveys, seismic studies,
production history, cost estimation, drilling reports, Geology, records of (bit, mud, mud-logging
and operator drilling), Scout tickets and Log headers.
3. Drilling Hazards:
Drilling hazards can be deep or shallow gas, unconsolidated sand, loss of circulation or
overpressure zones, and sections of hard impervious rock which can be known from geological
structures that overlay on targeted formation by drilling.
4. Drill stem test:
The drill stem test (DST) is the principal way to test a
formation that has just been drilled. A DST tool is run
into the hole, formation fluids flow into a perforated pipe
in the tool. Reservoir characteristics that may be
estimated from (DST) analysis include: Average
effective permeability, Reservoir pressure, Identify
reservoir fluids, Well-bore damage, Barriers fluid
contacts, Radius of investigation and Depletion.
5. Casing:
The casing shall be designed with respect to realistic load
conditions during the lifetime of the well.
The load shall be corrected for additional loads and
effects: biaxial stress – collapse, casing wear, bending in
deviated hole sections, temperature effects, corrosion,
plastic formations and reservoir compaction, pressure
during completion, workover and kill operations.
6. Cementing:
When cementing the conductor casing, the requirement
that it shall be capable of providing the necessary support
for the surface casing and also be capable of absorbing
the forces that occur when well control equipment is
placed on the sea bed, shall be taken in to consideration.
3
The surface casing shall be planned cemented so that
sufficient vertical and lateral support is achieved.
Producing casing is cemented so all permeable intervals
with abnormal pressure and zones containing
hydrocarbons are to be isolated, the cement shall be of
such quality and shall have sufficient compression
strength so as to be able to resist expected pressure in the
next section, and provide a reliable and permanent seal
against permeable formations in the cemented area.
7. Well head and X-mas tree:
Well head is required to control pressure during drilling
and production, and serve as a point to suspend casing &
tubing strings, as well as a connection to the surface
pressure-control equipment, i.e. blow out preventer (BOP) (during drilling stage) and christmas
tree (during production stage). It also allows access to a live well (under pressure), in a safe and
controlled manner. A wellhead consists of heads, hangers, spools and a series of seals.
Christmas tree consists of chokes, valves and spools. The main purpose of christmas tree is to
control the flow of well fluids or gas during production. Additional functions of christmas tree
include pressure relief, chemical injection, a conduit for control systems to monitor and control
safety valves in down-hole.
8. Estimation of items:
All items should be checked which are used in well design. They can be bits, casing, shale shaker,
blowout preventer, X-mas tree, cementing and well head etc.
4
9. Time and cost estimation:
Documents for well design should be issued for approval and proper estimated time and cost
should be decided and authorized for expenditure.
10. Equipments:
Approval should be done to place order for the required items for well design.
BLOWOUT PREVENTER
CEMENTING UNITS
SHALE SHAKER
5
KELLY RIG
CASING
11. Starting Date:
Starting date should be approved, after completion of well design (availability of items, approved
documents).
CONCLUSION
These are the steps followed to design a well. For well design engineers think the possible worst
can be happening in well on that basis all well designing is started, all items are ordered and
estimation of costs. All the safety measures taken on this basis.
REFERENCES
1. https://petrowiki.org/PEH:Introduction_to_Well_Planning
2. https://www.academia.edu/8361169/Well_Completion_Design_-_Jonathan_Bellarby
