Controlling fluid loss in oil and gas wells
First Claim
1. A system for controlling fluid loss in a target formation in an oil or gas well, the well comprising a wellbore extending from a well head at the surface through a target formation, the system comprising:
- a tubular conduit having a diameter small enough to be received in the wellbore and having a length sufficient to extend from the well head to the target formation;
a volume of delivery fluid; and
a load of fluid control pods, wherein each pod comprises a discrete mass of swelling agent contained within a container formed of porous, deformable, elastic material, wherein each pod is sized to pass through the conduit into the target formation with the delivery fluid so that the load of pods can be pumped into the formation through the conduit using the delivery fluid, wherein the container material allows the swelling agent to swell but to keep the pod intact in the formation, and wherein the container material has a frictional surface that will frictionally engage surfaces of the formation and surfaces of adjacent pods in the load of pods.
0 Assignments
0 Petitions
Accused Products
Abstract
A product, system and method for controlling fluid loss in oil wells, including lost circulation while drilling wells. A load of fluid control pods is pumped down the drill string into the target formation using water, drilling mud or another suitable delivery fluid. Each pod comprises a discrete mass of swelling agent with a frictional surface. Preferably, the pod comprises superabsorbent granules inside a fabric sack that is deformable and elastic and provides the frictional surface. After the pods have time to swell and become compressed against each other in the voids, drilling or other procedures may be continued. The size and frictional surface of the pods facilitates stable positioning of the pods in the voids of the formation, minimizes the total amount of swelling agent required, and reduces the tendency of the pods to become dislodged.
53 Citations
32 Claims
-
1. A system for controlling fluid loss in a target formation in an oil or gas well, the well comprising a wellbore extending from a well head at the surface through a target formation, the system comprising:
-
a tubular conduit having a diameter small enough to be received in the wellbore and having a length sufficient to extend from the well head to the target formation; a volume of delivery fluid; and a load of fluid control pods, wherein each pod comprises a discrete mass of swelling agent contained within a container formed of porous, deformable, elastic material, wherein each pod is sized to pass through the conduit into the target formation with the delivery fluid so that the load of pods can be pumped into the formation through the conduit using the delivery fluid, wherein the container material allows the swelling agent to swell but to keep the pod intact in the formation, and wherein the container material has a frictional surface that will frictionally engage surfaces of the formation and surfaces of adjacent pods in the load of pods. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
-
-
14. A method for controlling fluid loss in a target formation in an oil or gas well, wherein the well comprises a wellbore extending from a well head at the surface to a target formation, the method comprising:
depositing a plurality of fluid control pods into the target formation, wherein each pod comprises a discrete mass of swelling agent contained within a container formed of porous, deformable, elastic material that provides the container with a frictional surface so that the pod will swell but remain intact when deposited in the formation causing the frictional surface of the pod container to frictionally engage surfaces of the formation and surfaces of adjacent pods. - View Dependent Claims (15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26)
- 27. A fluid control pod for use in controlling fluid loss in a target formation in a well, the pod comprising a preselected amount of a granular swelling agent within a porous container that is elastic and deformable and has a frictional surface capable of frictionally engaging surfaces of the formation and surfaces of adjacent pods when multiple pods are deposited in the formation and swell in response to fluids in the formation.
Specification