CA2503040A1

CA2503040A1 - Wound spring wire screen for downhole injection and recovery

Info

Publication number: CA2503040A1
Application number: CA 2503040
Authority: CA
Inventors: Jason Swist
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-03-30
Filing date: 2005-03-30
Publication date: 2006-09-30

Abstract

A wound spring wire screen providing for the injection of steam into a formation that prevents, eliminates and/or controls the potential for the intrusion of granular particulates, that can plug or clog a downhole steam injection system, within a well bore.

Description

Description BACKGROUND OF THE INVENTION
1. Field of the Invention The present invention relates to downhole screens used in the production of oil and jas.

2. Description of the Prior Art There are numerous downhole screen designs on available on the market, they range from slotted liner to welded wire mesh to simple aggregate or gravel packs.
SUMl~~(ARY OF THE INVENTION

Now, in accordance with the present invention, couplers that attach to the downhole pipe are provided for that allow for the attachment of the wound spring wire screen to the injection pipe. These couplers are located at each end of the screen and securely locate the screen to the pipe or to successive screens. The invention provides for a screening mechanism to control the collection of particulates in the inflow stream by preset coil gaps in the wound wire. The larger the gap between the coils the less particulates are effectively screened, but the higher the flow rate accorded. By knowing the size of the downhole particulates that are to be screened, the coil gap can easily be preset on a lathe with the appropriate size mandrel and wire. Once the required gap has been determined the wire is wound to the required outside diameter of the well bore and then attached to the mating collars. The invention also provides for stabilizing ribs to be present between the two mating collars on the opposite ends of any particular screen to ensure structural integrity of the screen as well as to fix the distance between the two collars thereby ensuring the coil gap width remains constant at all times.
Thus it is an object of the present invention to provide an easily produced novel downhole injection or recovery screen for oil or gas well bores.
Further objects and features of the present invention will become apparent upon reading the following description together with the drawing.
BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a perspective view of a triangular wire screen assembly according to the invention;
FIG. 2 is a side view of a screen assembly according to the invention;
FIG. 3 is an end on side view of a screen assembly according to the invention.
DESCRTPTION OF THE PREFERRED EMBODIMENT
The wound wire spring screen according to the invention would be most commonly used during the injection or recovery process associated with oil and gas. These down hole screens are required during the injection of steam or chemicals into a formation as well as during subsequent recovery of oil. The screen acts as a filter preventing sand and other contaminants from clogging the inlets during insertion as well as preventing them from being collected with the oil or gas during the recovery process.
Due to the nature of the areas where oil and gas reserves are found, there are usually associated formations of sand, gravel, rock or other materials in the immediate vicinity.
During both set up and recovery the idea is to allow for the highest flow rate possible into or out of the formation while being able to adequately screen out contaminants that will reduce flow, clog screens, filters and the like while also ruining pumps and ancillary equipment. The proposed invention allows for maximum flow rates in both directions due to the nature of the spring wire windings and the ability to easily adjust the coil gap distances while also providing for an unmatched total flow area over the entire screen surface.
By employing a dii~ering cross-section wire such as triangulated spring wire it is possible to provide a wound spring wire screen which presents a completely flat surface towards the formation, which substantially reduces the ability for particulates to accumulate on the exterior screen wall or in the windings themselves and therefore clog the screen.
The proposed invention will therefore provide a novel downhole screen with improved inflow and outflow characteristics.
The proposed invention in its preferred embodiment, attaches to the insertion or recovery pipe via coupling collars, providing for a unobstructed flow of fluids into or out of the recovery pipe. The invention consists of a preset coiled spring wire assembly with coupling means at each end. The spring wire is wound on a mandrel to the desired external and/or internal dimensions required for the downhole application. The assembly is then removed from the mandrel and the desired coupling means is attached to each end of the windings. The assembly is then structurally braced to provide for a consistent coil gap size as while as to increase the strength of the assembly.
DRAWINGS

Details of wound spring wire screen 10 made with triangular wire 11 are depicted in FIG.
1.
Details of wound spring wire screen 10 with triangular wire 11 and external bracing 14 and coupling ends 12 are depicted in FIG. 2.
Details of wound spring wire screen 10 with triangular wire 1 l and external bracing 14 and coupling ends 12 and intake/exhaust port 16 are depicted in FIG. 3.
While the present invention has been described with relation to a specific embodiment, it is not intended to be limited thereto. For example, the wound spring wire element may be of a single or multiple wire configurations. Also, while a single wound spring wire element has been described, a plurality of wound spring wire screens may be employed concentrically or side-by-side can be utilized without departing from the inventive concept. Thus it is the intention to cover the invention as set forth within the full scope of the claims.

Claims

1. A wound spring wire screen that utilizes the gaps between the wire coils as a screening mechanism allowing for injection of steam or other fluids into an oil or gas formation that prevents the intrusion or collection of particulates in the injection pipe while also providing for increased fluid flow into and out of the formation.

2. A wound spring wire screen that provides for a preset or variable particulate screening size by variance of the coil gap.

3. A wound spring wire screen that provides for a preset or variable particulate screening size by variance of the wire mil size.

4. A wound spring wire screen that provides for a variable particulate screening size by variance of the coil gap, the wire mil size and/or a combination of both.

5. A wound spring wire screen that provides for substantial gains in inflow or outflow due to the increase in available screen surface port open area due to the size of the wire, the number of windings and the gap between the coils.

6. A wound spring wire screen with internal or external ribbing and/or supports to maintain a consistent gap between the wound coils.

7. A wound spring wire screen that creates an annulus between the down hole well casing and the wire windings to provide for increased flow into and out of the formation.

8. A wound spring wire screen utilizing a triangular spring wire design to provide for a difference in the cross-sectional area of the wire to reduce or prevent clogging.

9. A wound spring wire screen that leaves an open port through the center of the screen to allow for the passing through of down hole tooling.

10. A wound spring wire screen that provides for a coupling mechanism at each end to attach to the injection and/or recovery pipe.

11. A wound spring wire screen consisting of multiple smaller elements joined or banded together to form a larger single screening unit.

12. A wound spring wire screen with an adjustable coil gap fixture that allows for the gap to be opened up or closed down, to allow for the screening of various sized particulates as well as to facilitate the cleaning of the screen.