Patent ID: 6561280
Filing Date: 2003-05-13
Classification: E21B

Abstract:
A method of injecting tubing into partially horizontal pipe which has a larger diameter than said tubing, said method comprising(a) feeding tubing into the pipe, (b) attaching a thruster pig within about 5000 feet of an end of the tubing which is inserted into the pipeline, wherein said thruster pig comprises a body having an inner diameter greater than the outer diameter of the injected tubing and having an outer diameter equal to or smaller than the inner diameter of the pipe, an attaching apparatus adapted to attach the device to the end of the small diameter tubing or to the exterior of the small diameter tubing, a sealing apparatus to impede fluid migration between the body of the device and the inner surface of the pipe, an aperture allowing fluids pumped down the interior of the injected tubing to pass through the device into the interior of the pipe ahead of the device, and a means for allowing fluids to flow back through the device and up the annulus, (c) exerting pressure against said thruster apparatus, thereby causing the thruster pig to exert at lest a portion of the force necessary to inject the tubing down the pipe.