HEAT INSULATING CONTAINER FOR A DETONATOR

• US 20090090263A1
• Filed: 12/15/2008
• Published: 04/09/2009
• Est. Priority Date: 03/28/2006
• Status: Active Grant

• Current Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Original Assignee: Schlumberger Technology Corporation (Schlumberger NV)
• Inventors: Han, Chenghua, Duhon, Mark C.
• Granted Patent: US 7,673,566 B2
• Time in Patent Office: Days
• US Class Current: 102/322
• CPC Class Codes: E21B 36/003 Insulating arrangements
• CPC Class Codes: E21B 43/1185 Ignition systems
• CPC Class Codes: F42B 39/18 Heat shields; Thermal insulation
• CPC Class Codes: F42D 1/02 Arranging blasting cartridges to form an assembly adaptation of blasting cartridges therefor F42B3/02
• CPC Class Codes: Y10S 102/704 Coolants

Abstract

An apparatus for use in a wellbore comprises a heat insulating container having an inner space and having a structure defining a hollow containing a vacuum. The apparatus further comprises a reflective layer arranged on a surface of the heat insulating container to reflect heat for reducing radiated heat originated in the wellbore from reaching the inner space. Also, a signal-activated detonator is provided in the inner space of the heat insulating container.

Claims

1. A method for use in a wellbore, comprising:

lowering a tool having a heat insulating container and an explosive into the wellbore, wherein the heat insulating container has an inner space and a structure defining a vacuum layer, the tool further having a reflective layer arranged on a surface of the heat insulating container to reflect heat for reducing heat radiation from the wellbore into the inner space, and a signal-activated detonator provided in the inner space of the heat insulating container; and

activating the signal-activated detonator to cause detonation of the explosive.

2. The method of claim 1, wherein the tool is lowered to a depth in the wellbore at which the temperature is between 400°

F. and 600°

F.

3. The method of claim 2, wherein the tool remains in the wellbore in an environment with temperature between 400°

F. and 600°

F. for longer than one hour prior to activation of signal-activated detonator for detonating the explosive.

4. The method of claim 1, further comprising providing the reflective layer coated to the surface of the heat insulating container.

5. The method of claim 1, wherein lowering the tool having the heat insulating container comprises lowering the tool having the heat insulating container that comprises a thermal flask that provides the inner space in which the signal-activated detonator is provided.

6. The method of claim 1, wherein the heat insulating container has an opening, the method further comprising:

inserting the signal-activated detonator into the heat insulating container through the opening; and

inserting a plug to fit in the opening to seal the inner space in which the signal-activated detonator is provided.

7. The method of claim 6, further comprising:

extending a crimp tube through a through-bore of the plug;

inserting booster explosive into the crimp tube such that the booster explosive abuts the detonator;

ballistically connecting a detonating cord to the booster explosive in the crimp tube; and

crimping the crimp tube around the detonating cord to attach the detonating cord to the heat insulating container.