Plugs

Question 1

Name four reasons to plug a well

Answer 1

Zone Isolation, Lost Circulation, Directional Drilling, and Abandonment

Question 2

Four Functions When Using Plugs For Zone Isolation

Answer 2

1. Prevent Fluid Migration. 2. Unstick Drill Pipe. 3. Protect Pay Zone from Other Cementing Operations. 4. Create New Bottom of Well In Order To Isolate Upper Zone

Question 3

Cement Slurries Lost Into Three Types of Formations.

Answer 3

1. Formations with Large Pores, Vugs or Fractures
2. Formations with Moderate to Small Pores or Fractures
3. Formations with Low Permeability and Low Tensile Strength

Question 4

What Do Whipstock Plugs Do

Answer 4

1. Correct Excessive Vertical Deviation
2. Drill Relief Well
3. Drill Under A Salt Dome
4. Drill Toward Target Inaccessible by Vertical Drilling

Question 5

You will Set Plugs At The Following Locations for abandonment

Answer 5

1. Across and above any potential oil and gas producing zone.
   2 At the surface casing seat
   3 Above and Below Any Potable Water Bearing Zone
2. At The Surface Casing Seat, Fifty or More Feet Up Into The Surface Casing and Fifty or More Feet Below the Surface Casing
3. Three feet below ground level

Question 6

Types of Formations That Cause Poor Bonding

Answer 6

1. Salt Sections or Salt Stringers
2. Large Washouts In Unconsolidated Sands
3. Permeable Sections With A Thick Filter Cake Buildup
4. Water Sensitive Shale Sections

Question 7

In General, What is The Minimum Plug Length

Answer 7

200 Feet or 125 CU.FT

Question 8

Four Common Methods of Setting Cement Plug

Answer 8

1. Balanced
2. Dump Bailer
3. Two-Plug
4. Modified Two Plug

Question 9

Two Disadvantages of Balance Plug

Answer 9

1. Mud Contamination

2. Movement of Plug