Abstract: A vibration damping device for use with downhole electronics may comprise: a device housing mechanically coupled to the downhole electronics and defining a receptacle; and an inertia element movably supported in the receptacle; wherein the volume of the receptacle is greater than the volume of the inertia element so as to define an interstitial volume therebetween and wherein the interstitial volume is occupied by a fluid or an elastomer. A method for tuning a downhole torsional damping device to match a desired downhole electronics may comprise a) calculating a set of natural frequencies and mode shapes for the downhole electronics, b) selecting a desired frequency from the calculated natural frequencies, c) tuning the damping device characteristics to match the selected frequency, d) using the mode shapes to place the damping device. The mode shapes may include antinodes and step d) includes positioning a damping device at an antinode.

Abstract: A damping device for use with a downhole tool having a tool axis and an expected operational temperature range, may comprise a device housing mechanically coupled to the tool and including a volume; and an inertia element movably supported in the receptacle and having a volume, a mass, and a non-zero moment of inertia about the tool axis. The inertia element may be supported within the receptacle such that the inertia element can move relative to the device housing and an interface between the device housing and the tool may include an area-altering feature. The device housing has a coefficient of thermal expansion that allows the interface to transmit a predetermined amount of torque and a predetermined amount heat across at expected operational temperatures. The interface may include a thermally conductive material in thermal contact with the device housing and the tool.

Abstract: A damping device for use with a downhole tool having a tool axis and an expected operational temperature range, may comprise a device housing mechanically coupled to the tool and including a volume; and an inertia element movably supported in the receptacle and having a volume, a mass, and a non-zero moment of inertia about the tool axis. The inertia element may be supported within the receptacle such that the inertia element can move relative to the device housing and an interface between the device housing and the tool may include an area-altering feature. The device housing has a coefficient of thermal expansion that allows the interface to transmit a predetermined amount of torque and a predetermined amount heat across at expected operational temperatures. The interface may include a thermally conductive material in thermal contact with the device housing and the tool.

Abstract: A damping device for use with a downhole tool having a tool axis and an expected operational temperature range, may comprise a device housing mechanically coupled to the tool and including a volume; and an inertia element movably supported in the receptacle and having a volume, a mass, and a non-zero moment of inertia about the tool axis. The inertia element may be supported within the receptacle such that the inertia element can move relative to the device housing and an interface between the device housing and the tool may include an area-altering feature. The device housing has a coefficient of thermal expansion that allows the interface to transmit a predetermined amount of torque and a predetermined amount heat across at expected operational temperatures. The interface may include a thermally conductive material in thermal contact with the device housing and the tool.

Abstract: A damping device for use with a downhole tool having a tool axis and an expected operational temperature range, may comprise a device housing mechanically coupled to the tool and including a volume; and an inertia element movably supported in the receptacle and having a volume, a mass, and a non-zero moment of inertia about the tool axis. The inertia element may be supported within the receptacle such that the inertia element can move relative to the device housing and an interface between the device housing and the tool may include an area-altering feature. The device housing has a coefficient of thermal expansion that allows the interface to transmit a predetermined amount of torque and a predetermined amount heat across at expected operational temperatures. The interface may include a thermally conductive material in thermal contact with the device housing and the tool.

Abstract: A vibration damping device for use with a downhole tool having a tool axis may comprise a device housing mechanically coupled to the downhole tool, wherein the device housing defines a receptacle having a volume and an inner surface; an inertia element movably supported in the receptacle and having a volume, a mass, and a non-zero moment of inertia about the tool axis; wherein the inertia element volume is greater than the receptacle volume and an interstitial volume is defined between the inertia element and the receptacle, and wherein the interstitial volume is occupied by a fluid or an elastomer. The device may include a longitudinal bearing and/or a radial bearing between the inertia element and the receptacle. The device may also include a pressure compensation device in fluid communication with the receptacle and positioned within or an integral part of the device housing.

Abstract: A vibration damping device for use with a downhole tool having a tool axis may comprise a device housing mechanically coupled to the downhole tool, wherein the device housing defines a receptacle having a volume and an inner surface; an inertia element movably supported in the receptacle and having a volume, a mass, and a non-zero moment of inertia about the tool axis; wherein the inertia element volume is greater than the receptacle volume and an interstitial volume is defined between the inertia element and the receptacle, and wherein the interstitial volume is occupied by a fluid or an elastomer. The device may include a longitudinal bearing and/or a radial bearing between the inertia element and the receptacle. The device may also include a pressure compensation device in fluid communication with the receptacle and positioned within or an integral part of the device housing.

Abstract: A vibration damping device for use with a downhole tool having a tool axis may comprise a device housing mechanically coupled to the downhole tool, wherein the device housing defines a receptacle having a volume and an inner surface; an inertia element movably supported in the receptacle and having a volume, a mass, and a non-zero moment of inertia about the tool axis; wherein the inertia element volume is greater than the receptacle volume and an interstitial volume is defined between the inertia element and the receptacle, and wherein the interstitial volume is occupied by a fluid or an elastomer. The device may include a longitudinal bearing and/or a radial bearing between the inertia element and the receptacle. The device may also include a pressure compensation device in fluid communication with the receptacle and positioned within or an integral part of the device housing.

Abstract: A vibration damping device for use with downhole electronics may comprise: a device housing mechanically coupled to the downhole electronics and defining a receptacle; and an inertia element movably supported in the receptacle; wherein the volume of the receptacle is greater than the volume of the inertia element so as to define an interstitial volume therebetween and wherein the interstitial volume is occupied by a fluid or an elastomer. A method for tuning a downhole torsional damping device to match a desired downhole electronics may comprise a) calculating a set of natural frequencies and mode shapes for the downhole electronics, b) selecting a desired frequency from the calculated natural frequencies, c) tuning the damping device characteristics to match the selected frequency, d) using the mode shapes to place the damping device. The mode shapes may include antinodes and step d) includes positioning a damping device at an antinode.

Abstract: An interface tool and apparatus for retrieving a tubing from a well at least partly filled with a liquid, the tubing having first and second end portions. The apparatus includes an anchor for engaging tubing; sealing module for sealing first end portion of the bore of tubing; injector for injecting a low density fluid into tubing in or at an elevation below sealing module; and sealing cable connecting to a surface of the well. Apparatus includes first and second tool string sections, and interface tool configured for connecting first tool string section and second tool string section.

Abstract: This invention relates to an interface tool and apparatus for retrieving a tubing from a well at least partly filled with a liquid, the tubing having first and second end portions. The apparatus includes means for engaging tubing; means for sealing first end portion of the bore of tubing; means for injecting a low density fluid into tubing in or at an elevation below, sealing means; connecting means to a surface of the well. Apparatus includes first and second tool string sections, and interface tool configured for connecting first tool string section and second tool string section. First tool string section provided with engagement means, sealing means, injection means and connection means. The second downhole equipment provided with a sealing means for closing the second end portion of tubing, such as a mechanical plug having a check valve, and a cutting tool for cutting tubing underneath sealing means.