MODULE 12-DIRECTIONAL DRILLING 2

Question 1

What do all survey systems measure?

Answer 1

Inclination and azimuth at articular measured depths

Question 2

What are the 3 reference systems used?

Answer 2

Depth references
Inclination references
Azimuth references

Question 3

What are the 2 kinds of depths?

Answer 3

Measured or TVD

Question 4

How is measured depth measured?

Answer 4

distance measured along the actual course of the borehole from the surface reference point.

Question 5

How is TVD measured?

Answer 5

true vertical depth is the vertical distance from the depth reference level to a point on the borehole course.

Question 6

In most drilling operatios, what is used as the working death reference?

Answer 6

Rotary table(RT) or Kelly Bushing Elevation (KBE)

Question 7

Define Inclination reference

Answer 7

the angle that the well bore deviated from vertical

Question 8

What is the azimuth reference?

Answer 8

The azimuth is the angle int he horizontal plane measure clockwise from a fixed reference direction (True North)

Question 9

What is angle between magnetic north and true north called?

Answer 9

magnetic declination

Question 10

What are 4 causes of magnetic inference?

Answer 10

1. Drill string magnetization
2. Nearby cased wells
3. Nearby fish
4. Magnetic deposition in the formation

Question 11

What does a single shot survey instrument record?

Answer 11

inclination
direction
toolface

Question 12

What is the most common surveying tools for DD?

Answer 12

MWD

Question 13

What measurements can MWD take?

Answer 13

Gamma Ray
Compass direction
Tool Face
Borehole pressure
Temperature
Vibration
Torque
Shock

Question 14

MWD surveys every?

Answer 14

30-500ft or 10m to 150m

Question 15

How often can the MWD survey?

Answer 15

after every drilling joint. 9.5m when doing precise steering in reservoir.

Question 16

How far can the MWD go during an active change in angles

Answer 16

90ft

Question 17

How far can the MWD go while drilling straight ahead

Answer 17

200-300ft

Question 18

How does MWD tool work?

Answer 18

sends pressure pulses up the mud column inside the drillstring

Question 19

How are the pulses picked up on a MWD tool?

Answer 19

picked up by a transducer installed on the standpipe

Question 20

What are the binary code data rates for MWD tool?

Answer 20

1.5 to 40 bits/s

Question 21

3 type of tool modulation mechanisms?

Answer 21

positive pulse
negative pulse
Continuous wave

Question 22

Positive Pulse

Answer 22

Creates a restriction on the inside of the drill pipe and cause a positive pulse

Question 23

Negative Pulse

Answer 23

Opens a discharge valve in the annulus and causes a negative pulse

Question 24

Continuous wave

Answer 24

Gradually open and close valve.

Create Sine wave

Question 25

EM tool is another form of?

Answer 25

MWD tool

Question 26

How is the signal sent to receivers from the EM tool?

Answer 26

via EM waves up through formations to receivers

Question 27

What is the best EM application?

Answer 27

Underbalance drilling because of signal attenuation

Question 28

What are the EM limitations?

Answer 28

Depth (battery life)

Certain formations attenuate EM waves (salt)

Question 29

What does EM eliminate?

Answer 29

the need to use fluid as a medium