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Swellable Overshot

IP.com Disclosure Number: IPCOM000185130D
Publication Date: 2009-Jul-13
Document File: 2 page(s) / 101K

Publishing Venue

The IP.com Prior Art Database

Abstract

Tubular goods in oil and gas wells may become parted for various reasons. It is beneficial to be able to repair these pipes and to enable a hydraulic seal between the two sections. Such devices are sometimes manufactured with lead seals and enabled by applying compressive force and are frequently known as overshots when the upper tubular containing the sealing mechanism is placed over and swallows the lower member or stump. The device described herein is such an overshot device and uses swellable rubber as the sealing mechanism.

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Swellable Overshot

016492

Abstract:

Tubular goods in oil and gas wells may become parted for various reasons. It is beneficial to be able to repair these pipes and to enable a hydraulic seal between the two sections. Such devices are sometimes manufactured with lead seals and enabled by applying compressive force and are frequently known as overshots when the upper tubular containing the sealing mechanism is placed over and swallows the lower member or stump. The device described herein is such an overshot dev ice and uses swellable rubber as the sealing mechanism.

Description:

The swellable overshot has swellable rubber affixed to the inner diameter of the bottom end of a section of pipe which is desired to be joined with a pre-existing section of pipe. Th e upper section is lowered over the lower section, which has parted from a pipe which likely has been removed from the well.

The rubber seal swells after exposure to an activating fluid, such as a hydrocarbon or aqueous fluid (gas or liquid) which causes the swellable material to swell. The activating fluid could be produced or injected into the oil or gas well, or it could be carried down in a chamber within the swellable overshot and activated on demand, for example, by a telemetric signal from the surface, or with a timer or other actuating mechanism.

The device may include mechanisms to ensure that the two pipe sections are centralised and also that there has bee...