Abstract: The invention relates to a cementing tool for use in oil and gas well decommissioning operations, in particular so called perforate, wash and cement procedures. The tool (1) is designed for running in a well on drill string and for jetting cement through previously formed perforations in the casing (10) to fill the outer annulus (9) with cement. The tool (1) has a cylindrical wall (3) which is formed from steel (11) and elastomeric (5) elements, whereby it is expandable between a first diameter in which it may be run down the well and a second, larger diameter deployed during cementing operations. (FIG. 2).

Abstract: The present disclosure provides more efficient techniques for removing a host from a multi-host database system. An instruction to remove a host system may be received. In response, a determination of whether the first host system does or does not store any source tables is made based on a host-type identifier for the host system. This determination may not require obtaining landscape information for each of the hosts in the database system. If the host system stores replica tables and does not store source tables, those replica tables may be dropped based on the determination that the first host system does not store any source tables. As such, in cases where table redistribution is not needed the landscape information is not obtained, thereby making the host removal process more efficient.

Abstract: The invention relates to a cementing tool for use in oil and gas well decommissioning operations, in particular so called perforate, wash and cement procedures. The tool (1) is designed for running in a well on drill string and for jetting cement through previously formed perforations in the casing (10) to fill the outer annulus (9) with cement. The tool (1) has a cylindrical wall (3) which is formed from steel (11) and elastomeric (5) elements, whereby it is expandable between a first diameter in which it may be run down the well and a second, larger diameter deployed during cementing operations.

Abstract: The invention relates to a method of conducting a perf wash cement (“P/W/C”) abandonment job in an offshore oil or gas well annulus, in particular the washing or cementing operation using a rotating head with nozzles dispensing wash fluid or cement at pressure. A new design of bottom hole assembly is proposed in which the cementing tool has a relatively large diameter in order to optimize pressure whilst the wash tool has a relatively small diameter. The wash process, for a number of reasons, appears to be less sensitive to tool diameter and making the wash tool smaller reduces the overall risk of stuck pipe.

Abstract: The invention relates to a method of conducting a perf wash cement (“P/W/C”) abandonment job in an offshore oil or gas well annulus (2), in particular the washing or cementing operation using a rotating head (6, 8) with nozzles (7, 9) dispensing wash fluid or cement at pressure. Certain values of parameters of a washing or cementing job have been found surprisingly to affect the quality of the job, or the degree to which they affect the quality of the job has been unexpected. These include including rotation rate of the tool, the direction of translational movement of the tool, and the volume flow rate and pressure per nozzle of cement or wash fluid (and hence nozzle size).

Abstract: The invention relates to a method of conducting a perf wash cement (“P/W/C”) abandonment job in an offshore oil or gas well annulus, in particular the washing or cementing operation using a rotating head with nozzles dispensing wash fluid or cement at pressure. A new design of bottom hole assembly is proposed in which the cementing tool has a relatively large diameter in order to optimize pressure whilst the wash tool has a relatively small diameter. The wash process, for a number of reasons, appears to be less sensitive to tool diameter and making the wash tool smaller reduces the overall risk of stuck pipe.

Abstract: The invention relates to a method of conducting a perf wash cement (“P/W/C”) abandonment job in an offshore oil or gas well annulus (2), in particular the washing or cementing operation using a rotating head (6, 8) with nozzles (7, 9) dispensing wash fluid or cement at pressure. Certain values of parameters of a washing or cementing job have been found surprisingly to affect the quality of the job, or the degree to which they affect the quality of the job has been unexpected. These include including rotation rate of the tool, the direction of translational movement of the tool, and the volume flow rate and pressure per nozzle of cement or wash fluid (and hence nozzle size).

Abstract: This disclosure describes a device and method of sealing perforations on a well casing inside a subterranean well. The device comprises a generally cylindrical sleeve having an open top and a closed bottom; a heater located inside the sleeve, the heater comprising a thermite mixture; an ignition mechanism that ignites the thermite mixture upon actuation; and a string connected to the heater ignition and detachably engages the sleeve.

Abstract: Method of plugging a hydrocarbon well by a through-tubing technique are described. The method allows the tubing to be left in place. Only a short (<2 m) section is cut, milled, perforated, ruptured and expanded, or combinations thereof. A blocking device is sent downhole to block a bottom of the plug section, and bismuth alloy pellets dropped onto the blocking device. A heater is deployed to melt the bismuth alloy pellets. Next, the alloy liquid is allowed to cool and solidify. During solidification, the alloy expands and fills the section of well to be plugged or a portion thereof. Once primary and secondary barriers are in place, the well can be closed and the Christmas tree removed. A rock-to-rock plug can be set by removing or partially removing the tubular and outer casing, or just inner casing/tubulars can be removed if the exterior cement and casing are of sufficient quality.

Abstract: This disclosure describes a device and method of sealing perforations on a well casing inside a subterranean well. The device comprises a generally cylindrical sleeve having an open top and a closed bottom; a heater located inside the sleeve, the heater comprising a thermite mixture; an ignition mechanism that ignites the thermite mixture upon actuation; and a string connected to the heater ignition and detachably engages the sleeve.

Abstract: Method of plugging a hydrocarbon well by a through-tubing technique are described. The method allows the tubing to be left in place. Only a short (<2 m) section is cut, milled, perforated, ruptured and expanded, or combinations thereof. A blocking device is sent downhole to block a bottom of the plug section, and bismuth alloy pellets dropped onto the blocking device. A heater is deployed to melt the bismuth alloy pellets. Next, the alloy liquid is allowed to cool and solidify. During solidification, the alloy expands and fills the section of well to be plugged or a portion thereof. Once primary and secondary barriers are in place, the well can be closed and the Christmas tree removed. A rock-to-rock plug can be set by removing or partially removing the tubular and outer casing, or just inner casing/tubulars can be removed if the exterior cement and casing are of sufficient quality.

Abstract: The invention relates to a cementing tool for use in oil and gas well decommissioning operations, in particular so called perforate, wash and cement procedures. The tool (1) is designed for running in a well on drill string and for jetting cement through previously formed perforations in the casing (10) to fill the outer annulus (9) with cement. The tool (1) has a cylindrical wall (3) which is formed from steel (11) and elastomeric (5) elements, whereby it is expandable between a first diameter in which it may be run down the well and a second, larger diameter deployed during cementing operations. (FIG. 2).

Abstract: The invention relates to a method of conducting a perf wash cement (“P/W/C”) abandonment job in an offshore oil or gas well annulus, in particular the washing or cementing operation using a rotating head with nozzles dispensing wash fluid or cement at pressure. A new design of bottom hole assembly is proposed in which the cementing tool has a relatively large diameter in order to optimize pressure whilst the wash tool has a relatively small diameter. The wash process, for a number of reasons, appears to be less sensitive to tool diameter and making the wash tool smaller reduces the overall risk of stuck pipe.

Abstract: The invention relates to a cementing tool (1) and method for setting a cement plug. Instead of the conventional “balanced plug”, the technique involves pumping cement whilst pulling and rotating the tool. The cementing tool (1) includes nozzles (9) for jetting cement which are located in a relatively narrow region (8) of the tool and a larger diameter choke region (5) proximal of the nozzles (9). The end of the tool (11) is closed off and tapered. The tool is passed down the well to a location where it is desired to set a plug, then cement is injected whilst rotating and withdrawing the tool. The jets of cement help displace existing fluid in the well thereby reducing mixing of the existing fluid with the cement, The choke region (5) increases the flow energy, whilst the tapered end (11) helps prevent disruption to the cement as the tool is withdrawn.

Abstract: The invention relates to a method of conducting a perf wash cement (“P/W/C”) abandonment job in an offshore oil or gas well annulus (2), in particular the washing or cementing operation using a rotating head (6, 8) with nozzles (7, 9) dispensing wash fluid or cement at pressure. Certain values of parameters of a washing or cementing job have been found surprisingly to affect the quality of the job, or the degree to which they affect the quality of the job has been unexpected. These include including rotation rate of the tool, the direction of translational movement of the tool, and the volume flow rate and pressure per nozzle of cement or wash fluid (and hence nozzle size).

Abstract: The invention relates to a method of conducting a perf wash cement (“P/W/C”) abandonment job in an offshore oil or gas well annulus (2), in particular the washing or cementing operation using a rotating head (6, 8) with nozzles (7, 9) dispensing wash fluid or cement at pressure. Certain values of parameters of a washing or cementing job have been found surprisingly to affect the quality of the job, or the degree to which they affect the quality of the job has been unexpected. These include including rotation rate of the tool, the direction of translational movement of the tool, and the volume flow rate and pressure per nozzle of cement or wash fluid (and hence nozzle size).

Abstract: This disclosure describes a device and method of sealing perforations on a well casing inside a subterranean well. The device comprises a generally cylindrical sleeve having an open top and a closed bottom; a heater located inside the sleeve, the heater comprising a thermite mixture; an ignition mechanism that ignites the thermite mixture upon actuation; and a string connected to the heater ignition and detachably engages the sleeve.

Abstract: This disclosure describes a device and method of sealing perforations on a well casing inside a subterranean well. The device comprises a generally cylindrical sleeve having a open top and a closed bottom; a heater located inside the sleeve, the heater comprising a thermite mixture; an ignition mechanism that ignites the thermite mixture upon actuation; and a string connected to the heater ignition and detachably engages the sleeve.

Abstract: The invention relates to a method of conducting a perf wash cement (“P/W/C”) abandonment job in an offshore oil or gas well annulus (2), in particular the washing or cementing operation using a rotating head (6, 8) with nozzles (7, 9) dispensing wash fluid or cement at pressure. Certain values of parameters of a washing or cementing job have been found surprisingly to affect the quality of the job, or the degree to which they affect the quality of the job has been unexpected. These include including rotation rate of the tool, the direction of translational movement of the tool, and the volume flow rate and pressure per nozzle of cement or wash fluid (and hence nozzle size).

Abstract: Method of plugging a hydrocarbon well by a through-tubing technique are described. The method allows the tubing to be left in place. Only a short (<2 m) section is cut, milled, perforated, ruptured and expanded, or combinations thereof. A blocking device is sent downhole to block a bottom of the plug section, and bismuth alloy pellets dropped onto the blocking device. A heater is deployed to melt the bismuth alloy pellets. Next, the alloy liquid is allowed to cool and solidify. During solidification, the alloy expands and fills the section of well to be plugged or a portion thereof. Once primary and secondary barriers are in place, the well can be closed and the Christmas tree removed. A rock-to-rock plug can be set by removing or partially removing the tubular and outer casing, or just inner casing/tubulars can be removed if the exterior cement and casing are of sufficient quality.