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Well Drilling Engineering

Overview of Rotary Drilling Dr. DO QUANG KHANH

Contents

Introduction

Drilling Team

Steps to Drill a Well

Drilling Rigs

Offshore Drilling

Drilling Cost Analysis

(Drilling Economics)

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Fig: Role of drilling in field development

Introduction:

The life of an oil or gas field

can be sub-divided into the

following phases:

• Exploration

• Appraisal

• Development

• Maintenance

• Abandonment

Fig. 1.3 - Typical drilling rig organization

Personnel involved in drilling a well

Fig. 1.4

The

rotary

drilling

process

Steps to Drill A Gas/Oil Well

1. Complete or obtain seismic, log,

scouting information or other data.

2. Lease the land or obtain concession.

3. Calculate reserves or estimate from best

data available.

4. If reserve estimates show payout,

proceed with well.

5. Obtain permits from conservation/

national authority.

Steps to Drill a Well - cont’d

6. Prepare drilling and completion

program.

7. Ask for bids on footage, day work, or

combination from selected drilling

contractors based on drilling

program.

8. If necessary, modify program to fit

selected contractor equipment.

Steps to Drill a Well - cont’d

9. Construct road, location/platforms and other marine equipment necessary for access to site.

10. Gather all personnel concerned for meeting prior to commencing drilling

(pre-spud meeting)

11. If necessary, further modify program.

12. Drill well.

Steps to Drill a Well - cont’d

13. Move off contractor if workover unit

is to complete the well.

14. Complete well.

15. Install surface facilities.

16. Analysis of operations with

concerned personnel.

Drilling Operations Field Engineers, Drilling Foremen

A. Well planning prior to SPUD

B. Monitor drilling operations

C. After drilling, review drilling results and

recommend future improvements

- prepare report.

D. General duties.

What are the well requirements?

Objectives, safety, cost

Making

a

Connection

Making

a

Trip

Making a mouse hole connection

Making a mouse hole connection - cont’d

Single

Added.

Ready to

Drill

Moving Kelly

to Single in

Mousehole

Stabbing

the Pipe

Use

Elevators

for

tripping

Making a trip

Put Kelly in

Rathole

Why

trip?

Making a trip - cont’d

Tripping

one stand

at a time

60-90 ft

Fig. 1.5

Classification

of rotary

drilling rigs

Noble

Drilling’s

Cecil

Forbes

A Jack-

Up Rig

Sonat’s

George

Washington

A Semi-

Submersible

Rig

Zapata’s

Trader

A

Drillship

Deep Water Development Options

SUBSEA

COMPLET

IONS

FIXED

PLATFO

RMS COMPLI

ANT

TOWER

S FLOATIN

G

PRODUC

TION

SYSTEM

S

TENSIO

N LEG

PLATFO

RMS

TENSION LEG PLATFORM

Shell’s

Auger

Tension

Leg

Platform

Shell’s

Bullwinkle

World’s tallest

offshore

structure

1,353’ water

depth

Production

began in 1989

45,000 b/d

80MM scf/d