Patent ID: 8123888
Filing Date: 2012-02-28
Classification: B29C,B29K,E21B

Abstract:
1. A method of constructing an oilfield tubular, comprising: combining a fiber material and a high temperature thermoset resin comprising bismaleimide to create a composite material, the high temperature thermoset resin having a melting temperature in an uncured state at which temperature the high temperature thermoset resin liquefies sufficiently for forming; forming the composite material into a structure by winding the composite material around a mandrel while applying sufficient heat to the composite material at the point of winding to maintain the high temperature thermoset resin above its melting temperature; and heat curing the composite material to complete the oilfield tubular, wherein the heat curing process comprises: a pre-cure step consisting of exposing the composite material to a temperature of 300° F., increasing the temperature to 350° F. at a uniform rate of 5° F. per minute over a period of 10 minutes, holding the temperature at 350° F. for a period of 30 minutes, and decreasing the temperature to ambient at a uniform rate of 5° F. per minute or less; a main cure step consisting of raising the temperature of the composite material from ambient to 400° F. at a uniform rate of 5° F. per minute for 64 minutes, holding the temperature at 400° F. for a period of 120 minutes, and decreasing the temperature to ambient at a uniform rate of 5° F. per minute or less; and a post-cure step consisting of raising the temperature of the composite material from ambient to 482° F. at a uniform rate of 5° F. per minute, holding the temperature at 482° F. for a period of 360 minutes, and decreasing the temperature to ambient at a uniform rate of 5° F. per minute or less.