Abstract: A method for completing multi-lateral wells and maintaining selective re-entry into laterals is presented. In accordance with the present invention, a first lateral well is drilled from a primary well bore and a string of external casing packers and a packer bore receptacle are run therein. Once the orientation of the packer bore receptacle is determined, an orientation anchor of a retrievable whipstock assembly is mounted thereto. Thereafter, a second lateral well may be drilled. Once the second lateral well is drilled, the whipstock assembly may be retrieved and replaced with a scoophead diverter assembly which also includes an orientation anchor for mating with the packer bore receptacle. At this time, a string of external casing packers may be run into the second lateral well through the scoophead diverter assembly. Finally, a selective reentry tool is run into the scoophead assembly. The selective re-entry tool includes a diversion flapper for selecting either the first or second lateral well bore.

Abstract: The present invention relates to two improved methods for multilateral completion and cementing (e.g. sealing) the juncture between primary and lateral wellbores. These two completion methods of the present invention address the issue of cementation of the lateral wellbores for the purpose of zonal isolation. It is desirable to have the ability to re-enter each lateral wellbore as well as maintain the option to perform any function that could be done in a single wellbore. For this reason, cemented lateral wellbores are desirable so that normal isolation, stimulation or any other operation can be achieved. The methods allow sealing and reworking of either wellbores with single laterals or multiple laterals and provide safe durable junctions therebetween.

Abstract: In accordance with the present invention, a plurality of methods are provided for solving important and serious problems posed by lateral (and especially mutilateral) completion in a wellbore including methods for sealing the junction between a vertical and lateral well. Methods are disclosed for improved juncture sealing including novel techniques for establishing pressure tight seals between a liner in the lateral wellbore and a liner in the vertical wellbore. These methods generally relate to the installation of a liner to a location between the vertical and lateral wellbore such that the vertical well bore is blocked. Thereafter, at least a portion of the liner is removed to reopen the blocked vertical wellbore.

Abstract: A method is presented involving the use of measurement-while-drilling (MWD) devices and tools for well completion (including multi-lateral well completion). While MWD techniques have been known for many years and in that time, have gained wide acceptance, the use of MWD has been limited only to borehole drilling, particularly directional drilling. However, it has now been discovered that MWD may be advantageously used in wellbore completions and particularly multi-lateral completions. Examples of successful applications of MWD in completions are provided with regard to lateral wellbores which may be installed at depths of 10,000 ft. or more, and which range from vertical to horizontal. Such examples include the running of a scoophead/diverter assembly and a parallel seal assembly where it is desirable to align the tools at approximately the position at which they will engage with mating equipment.

Abstract: A method for completing multi-lateral wells and maintaining selective re-entry into laterals is presented. In accordance with the present invention, a first lateral well is drilled from a primary well bore and a string of external casing packers and a packer bore receptacle are run therein. Once the orientation of the packer bore receptacle is determined, an orientation anchor of a retrievable whipstock assembly is mounted thereto. Thereafter, a second lateral well may be drilled. Once the second lateral well is drilled, the whipstock assembly may be retrieved and replaced with a scoophead diverter assembly which also includes an orientation anchor for mating with the packer bore receptacle. At this time, a string of external casing packers may be run into the second lateral well through the scoophead diverter assembly. Finally, a selective reentry tool is run into the scoophead assembly. The selective re-entry tool includes a diversion flapper for selecting either the first or second lateral well bore.

Abstract: A novel scoophead/diverter assembly is presented which is installed at the juncture between a primary wellbore and a lateral branch and which allows the production tubing of each to be oriented and anchored. This scoophead/diverter assembly further provides dual seal bores for tying back to the surface with either a dual packer completion or a single tubing string completion utilizing a selective re-entry tool. The scoophead/diverter assembly comprises a scoophead, a diverter sub, two struts as connecting members between the scoophead and diverter sub and a joint of tubing communicating from the scoophead, thru the diverter sub, and to the primary wellbore. The scoophead has a large and small bore. The large bore is a receptacle for a tie back sleeve run on top of the lateral wellbore string, and the small bore is a seal bore to tie the primary wellbore back to surface. Below the scoophead, a joint of tubing is threaded to the small bore.

Abstract: In accordance with the present invention, a plurality of methods are provided for solving important and serious problems posed by lateral (and especially multilateral) completion in a wellbore including methods for sealing the junction between a vertical and lateral well. Methods are disclosed for improved juncture sealing including novel techniques for establishing pressure tight seals between a liner in the lateral wellbore and a liner in the vertical wellbore. These methods generally relate to the installation of a liner to a location between the vertical and lateral wellbore such that the verticle wellbore is blocked. Thereafter, at least a portion of the liner is removed to reopen the blocked verticle wellbore.

Abstract: In accordance with the present invention, a plurality of methods and devices are provided for solving important and serious problems posed by lateral (and especially multilateral) completion including methods and devices for re-entering selected lateral wells to perform completions work, additional drilling, or remedial and stimulation work. Various methods and devices are provided for assisting in the location and re-entry of lateral wells. Such re-entry devices include permanent or retrievable deflector (e.g., whipstock) devices. Preferably, the re-entry methods of this invention permit the bore size of the lateral wells to be the same or substantially the same bore size as the vertical wells.

Abstract: In accordance with the present invention, a plurality of methods and devices are provided for solving important and serious problems posed by lateral (and especially multilateral) completion in a wellbore including methods and devices for isolating a lateral well from other lateral branches in a multilateral well so as to prevent migration of fluids and to comply with regulations regarding the separate production of different production zones. Various methods and devices are provided for fluid isolation of a lateral well from other lateral wells and for separate production from a lateral well without commingling the production fluids. These methods include the use of a side pocket mandrel, whipstocks with sealable bores and valving techniques wherein valves are located at the surface or downhole at the junction of a particular lateral.

Abstract: A two-stroke cycle internal combustion engine has a sustained power stroke which results from delayed mixing of a stratified charge. Use of delayed mixing of an overall stoichiometric air-fuel mixture results in formation of a low amount of the oxides of nitrogen. Delayed mixing of a stratified charge is achieved by placement of a Helmholtz resonator cavity in the piston and peripherally just below the crown thereof. The Helmholtz resonator cavity communicates with the combustion chamber via a narrow slot made by undercutting the top edge of the piston. A port type intake valve is used. Pressurized air passing through the intake port during the exhaust phase of the cycle streams past the undercut top edge of the piston. After the engine cylinder has received a charge of fresh air the compression stroke is begun and the main chamber is filled with a slight fuel-rich gaseous charge. The companion Helmholtz resonator cavity receives only an air charge from the intake port.

Abstract: A four stroke cycle internal combustion engine is presented having a sustained power stroke which results from a delayed mixing of a stratified charge. Use of delayed mixing of an overall stoichiometric air-fuel mixture results in formation of a low amount of the oxides of nitrogen. Delayed mixing of the stratified charge is achieved by placement of at least one Helmholtz resonator cavity in the head or closed end of each combustion chamber. The Helmholtz resonator cavity communicates with the top end of the main combustion chamber via a narrow slot. On the intake stroke of each engine cylinder, the main chamber is filled with a slightly fuel rich gaseous charge while the companion Helmholtz resonator cavity is filled with air. During the compression stroke some of the rich air-fuel mixture is forced into the resonator cavity via the communicating slot. At or near TDC, the air-fuel mixture in the main chamber is ignited.

Abstract: A four stroke cycle internal combustion engine is presented having a sustained power stroke which results from a delayed mixing of a stratified charge. Use of delayed mixing of an overall stoichiometric air-fuel mixture results in formation of a low amount of the oxides of nitrogen. Delayed mixing of the stratified charge is achieved by placement of a Helmholtz resonator cavity in the head or closed end of each combustion chamber. The Helmholtz resonator cavity communicates with the main combustion chamber via a narrow slot made around the periphery of the top end of the chamber. On the intake stroke of each engine cylinder, the main chamber is filled with a slightly fuel rich gaseous charge while the companion Helmholtz resonator cavity is filled with air. During the compression stroke some of the rich air-fuel mixture is forced into the resonator cavity via the communicating slot. At or near TDC, the air-fuel mixture in the main chamber is ignited.