METHOD FOR STRENGTHENING A POLYETHYLENE TUBULAR MEMBER

1 . A method for strengthening a polyethylene tubular member, wherein the polyethylene tubular member has an outer surface, a circumference, a wall thickness, and an area to be strengthened, wherein the outer surface of the polyethylene tubular member comprises polyethylene, wherein the method comprises:

wrapping a fabric layer around the circumference of the tubular member at least two full rotations and covering the area to be strengthened, wherein the fabric layer comprises a plurality of interwoven tape elements comprising a base layer of a strain oriented olefin polymer disposed between covering layers of a heat fusible olefin polymer;

applying heat and optionally pressure to the fabric layer bonding the tape elements of the fabric layer together and bonding the tape elements and the tubular member together.

2 . The method of claim 1 , wherein the tape elements are adjacent to and in intimate contact with the tubular member.

3 . The method of claim 1 , wherein the fabric layer is wrapped around the circumference of the tubular member at least four full rotations.

4 . The method of claim 1 , further comprising wrapping a heat shrink film around the fabric layer before applying heat and optionally pressure.

5 . The method of claim 4 , wherein the heat shrink film is removed after heat and optionally pressure is applied.

6 . The method of claim 4 , wherein the heat shrink film extends on the outer surface of the tubular member at least about 1 inch past the fabric layer.

7 . The method of claim 1 , wherein the fabric layer is wrapped in a hoop or spiral wrapping pattern.

8 . The method of claim 1 , wherein the area to be strengthened comprises a damaged area extending from the outer surface of the tubular member at least partially through the wall thickness.

9 . The method of claim 1 , wherein the fabric layer consists essentially of thermoplastic polymer.

10 . A method of joining polyethylene tubular members together, wherein the polyethylene tubular members have an outer surface, a circumference, and a wall thickness, wherein the outer surfaces of the polyethylene tubular members comprise polyethylene, wherein the method comprises:

placing respective ends of the tubular members together forming a joint;

wrapping a fabric layer around the joint at least two full rotations, wherein the fabric layer comprises a plurality of interwoven tape elements comprising a base layer of a strain oriented olefin polymer disposed between covering layers of a heat fusible olefin polymer;

applying heat and optionally pressure to the woven fabric layer bonding the tape elements of the fabric layer together and bonding the tape elements and the tubular members together.

11 . The method of claim 10 , wherein the tape elements are adjacent to and in intimate contact with the tubular member.

12 . The method of claim 10 , wherein the fabric layer is wrapped around the circumference of the tubular member at least four full rotations.

13 . The method of claim 10 , further comprising wrapping a heat shrink film around the fabric layer before applying heat and optionally pressure.

14 . The method of claim 13 , wherein the heat shrink film is removed after heat and optionally pressure is applied.

15 . The method of claim 13 , wherein the heat shrink film extends on the outer surface of the tubular member at least about 1 inch past the fabric layer.

16 . The method of claim 10 , wherein the fabric layer is wrapped in a hoop or spiral wrapping pattern.

17 . The method of claim 10 , wherein the tubular members are joined end to end.

18 . The method of claim 10 , wherein the tubular members are joined together using a coupler.

19 . The method of claim 18 , wherein the method comprises joining two tubular members together.

20 . The method of claim 18 , wherein the method comprises joining three tubular members together.

21 . The method of claim 10 , wherein the fabric layer consists essentially of thermoplastic polymer.