Title 7. Plug-Back Cementing 779.4 KB 14
```                            Introduction
Topic Areas
Learning Objectives
Unit A: Purposes of Plug-Back Cementing
Plugging to Isolate Zones
Plugging to Stop Lost Circulation
Plugging for Directional Drilling
Plugging for Well Abandonment
Unit A Quiz
Unit B: Plug-Back Cementing Calculations
Balanced Plug Cementing
Example Using Equalization Point Formula
Balanced Plug Job One  (One Wellbore Geometry)
Calculations (Drillpipe Out)
Sacks Of Cement
Mixing Water
Calculations (Drillpipe In)
4  Height of Cement (HOC)
5  Height of Spacer Ahead (HOS)
6  Volume of Spacer Behind
7  Height of Mud
8  Volume Of Mud Behind (To Balance)
Working with a Fixed Amount of Spacer
5  Height of Spacer
6  Volume of Spacer (Behind Cement)
Balanced Plug Job Two (Two Wellbore Geometries)
Calculations (Drill Pipe Out)
Sacks Of Cement
Mixing Water
Calculations (Drillpipe In)
4  Height of Cement (HOC)
5  Height of Spacer (HOS)
6  Volume of Spacer Behind Cement
7  Height of Mud
8  Volume of Mud (To Balance)
Unit B Quiz
Answers to Unit Quizzes
```
##### Document Text Contents
Page 1

Section 7

Plug-Back Cementing

Introduction................................................................................................................................................7-3

Topic Areas ............................................................................................................................................7-3
Learning Objectives ...............................................................................................................................7-3

Unit A: Purposes of Plug-Back Cementing ...............................................................................................7-3
Plugging to Isolate Zones .......................................................................................................................7-3
Plugging to Stop Lost Circulation ..........................................................................................................7-4
Plugging for Directional Drilling ...........................................................................................................7-4
Plugging for Well Abandonment ...........................................................................................................7-5
Unit A Quiz ............................................................................................................................................7-6

Unit B: Plug-Back Cementing Calculations ..............................................................................................7-7
Balanced Plug Cementing ......................................................................................................................7-7
Example Using Equalization Point Formula ..........................................................................................7-8
Balanced Plug Job One (One Wellbore Geometry) ..............................................................................7-9
Balanced Plug Job Two (Two Wellbore Geometries)..........................................................................7-11
Unit B Quiz ..........................................................................................................................................7-13

Answers to Unit Quizzes .........................................................................................................................7-14

7 • 1 Cementing 1