Method and apparatus for removing mud from around and inside of casings

• US 5,360,292 A
• Filed: 07/08/1993
• Issued: 11/01/1994
• Est. Priority Date: 07/08/1993
• Status: Expired due to Term

• Current Assignee: Intermoor Inc (Willis Towers Watson France SAS)
• Original Assignee: Flow International Corporation (Shape Technologies Group Incorporated)
• Inventors: Allen, James R., LaLande, Alton J.
• Primary Examiner(s): Reese, Randolph A.
• Assistant Examiner(s): Ricci, John A.
• Application Number:
  US08/089,258
• Time in Patent Office: 481 Days
• Field of Search: 166/67, 166/68, 166/312, 175/67, 37/307, 37/317, 37/320, 37/321, 37/322, 37/323, 37/346, 405/195.1, 405/226, 405/228, 405/229, 405/232, 405/248, 405/249
• US Class Current: 405/249
• CPC Class Codes: E02B 17/00 Artificial islands mounted on piles or like supports, e.g. platforms on raisable legs or offshore constructions; Construction methods therefor construction methods for floating platforms B63B75/00; anchoring floating platforms B63B21/00; floating platforms, e.g. anchored, B63B35/44; underwater reservoirs B65D88/78
• CPC Class Codes: E02B 2017/0052 Removal or dismantling of offshore structures from their offshore location
• CPC Class Codes: E02B 3/023 Removing sediments in barrages or reservoirs E02B8/02
• CPC Class Codes: E02D 7/28 Placing of hollow pipes or mould pipes by means arranged inside the piles or pipes E02D13/08 takes precedence
• CPC Class Codes: E21B 7/18 Drilling by liquid or gas jets, with or without entrained pellets E21B7/14 takes precedence
• CPC Class Codes: Y02A 10/00 at coastal zones; at river basins

Abstract

A method and apparatus for removing mud from around and inside of a casing is shown and described. Examples of such casings include piles of offshore oil production platforms. In accordance with a preferred embodiment of the present invention, a submersible pump having a propeller and coupled to several nozzles is lowered to a position adjacent the mud to be removed. A volume of water is forced through the nozzles against the mud, the action of which, together with the propeller, serves to dilute and break up the mud. The submersible pump then forces the mud and water upward through a flexible tube to be discharged into open water.

Claims

1. A method for removing a mud plug from a casing comprising:

providing an opening in a side of the casing;

lowering a submersible pump provided with a discharge tube through the opening into the casing to a desired location adjacent the mud plug;

agitating the mud plug;

forcing a volume of fluid through a plurality of nozzles coupled to the submersible pump toward the mud plug thereby diluting the mud plug to form a slurry; and

pumping the slurry with the submersible pump out of the casing through the discharge tube.

2. The method according to claim 1, further comprising:

delivering 600-3000 gallons per minute of water at 150-500 psi toward an exposed surface of the mud plug.

3. A method for removing a mud plug from a casing comprising:

providing an opening in a side of the casing;

lowering a submersible pump provided with a discharge tube through the opening into the casing to a desired location adjacent the mud plug;

agitating the mud plug;

forcing a volume of fluid through a plurality of nozzles coupled to the submersible pump toward the mud plug thereby diluting the mud plug to form a slurry; and

pumping the slurry with the submersible pump out of the casing through the discharge tube.

4. The method according to claim 3, further comprising:

delivering 600-3000 gallons per minute of water at 150-500 psi toward an exposed surface of the mud plug.

5. A method for removing a mud plug from a casing comprising:

lowering a submersible pump provided with a discharge tube through an opening in a side of the casing to a desired location adjacent the mud plug;

agitating the mud plug;

forcing a volume of fluid through a plurality of nozzles coupled to the submersible pump toward the mud plug, thereby diluting the mud plug to form a slurry; and

pumping the slurry with the submersible pump out of the casing through the discharge tube.

6. A method for removing a mud plug from a casing comprising:

lowering a submersible pump provided with a discharge tube through an opening in a side of the casing to a desired location adjacent the mud plug;

forcing a volume of fluid through a plurality of nozzles coupled to the submersible pump toward the mud plug, thereby diluting the mud plug to form a slurry; and

pumping the slurry with the submersible pump out of the casing through the discharge tube.