Non-Metallic Mandrel and Element System
A non-metallic element system is provided as part of a downhole tool that can effectively seal or pack-off an annulus under elevated temperatures. The element system can also resist high differential pressures without sacrificing performance or suffering mechanical degradation, and is considerably faster to drill-up than a conventional element system. In one aspect, the composite material comprises an epoxy blend reinforced with glass fibers stacked layer upon layer at about 30 to about 70 degrees. In another aspect, a mandrel is formed of a non-metallic polymeric composite material. A downhole tool, such as a bridge plug, frac-plug, or packer, is also provided. The tool comprises a support ring having one or more wedges, an expansion ring, and a sealing member positioned with the expansion ring.
1 . A method assembling a tool for insertion into a tubular, comprising:
forming a mandrel of a polymeric composite;
forming a support ring of the polymeric composite, comprising:
forming a plurality of wedges, detachable from the support ring under pressure;
forming an expansion ring configured to fill gaps formed between the plurality of wedges;
disposing a sealing member about the mandrel;
disposing the expansion ring about the mandrel with the sealing member; and
disposing the support ring about the mandrel with the expansion ring.
2 . The method of claim 1 , wherein forming an expansion ring comprises:
forming the expansion ring of a material that flows at a predetermined temperature.
3 . The method of claim 1 , further comprising:
forming a cone from the polymeric composite; and
disposing the cone about the mandrel between the expansion ring and the sealing member.
4 . The method of claim 3 , wherein forming the expansion ring comprises:
tapering a section of the expansion ring to complement a sloped surface of the cone.
5 . The method of claim 1 , wherein the polymeric composite is reinforced by a fiber.
6 . The method of claim 1 , wherein forming a mandrel comprises:
winding a fiber impregnated with the polymeric composite material in layers at an angle of about 30 to about 70 degrees relative to an axis of the mandrel.
7 . The method of claim 1 , wherein forming the mandrel comprises:
winding a prepreg roving containing the polymeric composite material into layers at an angle of about 30 to about 70 degrees relative to an axis of the mandrel.
8 . The method of claim 1 , wherein forming a support ring of the polymeric composite material comprises:
winding a fiber impregnated with the polymeric composite material in layers at an angle of about 30 to about 70 degrees relative to an axis of the support ring.
9 . The method of claim 1 , wherein forming a plurality of detachable wedges comprises:
forming a first section of a first diameter;
forming a second section of a second diameter, connected to the first section, the first diameter less than the second diameter, angled outwardly from a center axis of the support ring at about 10 degrees to about 30 degrees; and
cutting longitudinal cuts into the second section, forming the plurality of wedges.
10 . The method of claim 9 , wherein forming an expansion ring comprises:
tapering a first section of the expansion ring at a complementary angle to the plurality of wedges.
11 . A method assembling a tool for insertion into a tubular, comprising:
forming a mandrel of a polymeric composite reinforced with fibers in layers at an angle of about 30 to about 70 degrees relative to an axis of the mandrel; and
disposing a sealing member about the mandrel, the sealing member configured to expand radially outward.
12 . The method of claim 11 , further comprising:
forming a support ring of the polymeric composite, comprising:
forming a plurality of wedges, detachable from the support ring under pressure;
forming an expansion ring configured to fill gaps between the plurality of wedges;
disposing the expansion ring about the mandrel with the sealing member; and
disposing the support ring about the mandrel with the expansion ring.
13 . The method of claim 12 , wherein forming an expansion ring comprises:
forming the expansion ring of a material that flows at a predetermined temperature.
14 . The method of claim 12 , further comprising:
forming a cone from the polymeric composite material; and
disposing the cone about the mandrel between the expansion ring and the sealing member.
15 . The method of claim 12 , wherein forming the expansion ring comprises:
tapering a section of the expansion ring to complement a sloped surface of the cone.
16 . The method of claim 12 , wherein forming a support ring of the polymeric composite material comprises:
winding a fiber impregnated with the polymeric composite material into layers at an angle of about 30 to about 70 degrees relative to an axis of the support ring.
17 . The method of claim 12 , wherein forming a plurality of detachable wedges comprises:
forming a first section of a first diameter;
forming a second section of a second diameter, connected to the first section, the first diameter less than the second diameter, angled outwardly from a center axis of the support ring at about 10 degrees to about 30 degrees; and
cutting longitudinal cuts into the second section, forming the plurality of wedges.
18 . The method of claim 17 , wherein forming an expansion ring comprises:
tapering a first section of the expansion ring at a complementary angle to the plurality of wedges.
19 . The method of claim 11 , wherein forming a mandrel comprises:
winding a fiber impregnated with the polymeric composite in layers at an angle of about 30 to about 70 degrees relative to an axis of the mandrel.
20 . The method of claim 11 , wherein forming the mandrel comprises:
winding a prepreg roving containing the polymeric composite material into layers at an angle of about 30 to about 70 degrees relative to an axis of the mandrel.