摘要:
A downhole motor (19) is mounted in a drill pipe (13) above a hole enlarger (14) intermediate ends of the pipe (13). The motor drives a lower pilot bit (28). A split flow bypass device (24) above the motor (19) allows part of the flow to drive the motor and the remainder to bypass through a central passage, the divided flows rejoining below the motor (19) with a restricted flow through jet nozzles (32) to the hole enlarger cutter (15). Flow passes centrally of the output shaft (26), past a bleed valve (34) bleeding up to 5% to an outer shaft space for lubricating bearings (30), to flow restrictor jet nozzles (33) of the pilot bit (28). In use flow is controlled to drive the motor (19) to drive the pilot bit (28) at desired speed and the drill string is rotated from the rotary platform of a drill rig to drive the hole enlarger (14) so that the hydraulic requirements of the hole enlarger (14) and the pilot bit (28) are met while only allowing sufficient fluid to pass through the motor (19) to give the required output speed at the pilot bit (28).
摘要:
A stabilizer sleeve (7) for a drill string, adapted to fit about a down hole motor (1) or a drill string member, is formed with an internally threaded coupling at a lower end for releasable coupling to complimentary threads (8) formed on an upwardly extending intermediate coupling portion (15) of a bottom coupling-nut (3). The coupling-nut (3) is provided with a lower end portion (14) of larger diameter and an upper coupling portion (16) of reduced diameter. The upper coupling portion (16) is conventionally formed with an upwardly tapering form and right-hand thread whereas the intermediate coupling portion (15) is formed with a left-hand thread. The stabilizer sleeve (7) fits about the motor (1) or other body member and above the coupling-nut (3) so that the sleeve (7) may be removed upwardly from the coupling-nut (3).
摘要:
A drop-ball sub-assembly comprises a tubular casing (4) defining a flushing fluid flow passage adapted for coupling at one end (3) to an inlet pipe (1) and at the other end (23) to an outlet pipe (24). A drop-ball (17) supporting member (8) is secured within the casing (4) in the flow passage. Apertures (21) are arranged to allow fluid flow past the supporting member (8), and a further aperture (9) supports a blow-out device (13) supporting a drop-ball (17) on a side distal from the end (23). The blow-out device (13) and the apertures (21,9) are such that at a first, lower fluid rate from the inlet (3) to the outlet (23) end, fluid flows through said aperture (21) and the blow-out device is retained, and that at a second, higher flow rate the blow-out device (13) is blown out of the further aperture to release the ball (17) through the further aperture (9). The blow-out device suitably comprises a frangible disc.
摘要:
A method of controlling the direction of a drill bit (3) at the downhole end of a drill string (2) drilling from a surface comprises providing two steerable stabilizers (4, 5) at the downhole end of the drill string (2) at locations spaced apart in the drilling direction and adjusting the orientation of the stabilizers to create reactive forces from the bore hole (6) to deflect the course of the bit (3) in a desired direction. The stabilizers (4, 5) are suitably arranged eccentrically and circumferentially offset by 180.degree..+-.60.degree.. In normal drilling the drill string (2) is rotated such that stabilizers (4, 5) engage the bore hole (6) to support a downhole motor (1) against tilting. When off course drilling is sensed the stabilizers are rotated to a position and stopped from rotation such that drilling forces generate reaction forces to cause a desired change of direction.
摘要:
This patent relates to biofuels, such as biodiesel and production of biofuels. One example, introduces a reactant to a renewable feedstock. The example produces a biofuel from the renewable feedstock and separates the reactant from the biofuel. The example recycles the reactant to react with additional renewable feedstock. The example also transfers heat from the recycled reactant to the additional renewable feedstock.
摘要:
An apparatus and a method are provided with the apparatus being arranged to control access to one or more resources in a computing device by one or more clients in said computing device. The apparatus further arranged to receive a request for access to a said resource from a first client, determine whether or not said resource is being used by a second client, and, if said resource is being used, remove said resource from said second client and provide said resource to said first client. The method and computer program correspond to the apparatus.
摘要:
The invention provides a method and system for solving a linear program having constraints in a production planning system. The invention first determines which of the constraints can be temporarily relaxed based on stocking point criteria. The stocking point criteria relates to time dependent stocking points that include part numbers, locations of parts identified by the part numbers, and the time periods when the parts will be available. The invention relaxes the constraints that can be relaxed and decomposes the linear program into smaller independent linear programs. The invention initially solves the smaller independent linear programs with relaxed constraints (simultaneously in parallel) to produce an initial solution. Next, the invention replaces variables in the linear program with constants based on this initial solution. After this the invention restores the material balance and sourcing constraints and finally solves (re-solves) the linear program using the constants and with all constraints in place to obtain a complete solution of the linear program.
摘要:
The invention comprises a method for achieving consideration of preemptive priorities within a supply chain optimization model. More specifically, the invention provides a method of allocating resources to a hierarchy of demand priorities in a linear programming production planning system. In particular, the invention aggregates the demand priorities into different priority groups and allocates the resources to the highest priority group of demand priorities using a first linear programming model. Next, the invention allocates remaining resources to the next highest priority group of demand priorities using a second linear programming model. The second linear programming model uses results from the first linear programming model. The invention continues this process by iteratively repeating the process of allocating remaining resources to the remaining groups of demand priorities, in order of priority. The system and method were employed to integrate the consideration of preemptive prioritization of customer demands with an advanced planning system for optimizing established planning objectives (e.g. customer service, short lead times, low inventory, and prioritized allocation of supply and capacity) to compute a feasible production plan for the division.
摘要:
A navigable downhole drilling system incorporating a drilling motor having a system of sensors and information processors for determining the depth, inclination, direction and thrust of the drilling motor. Accordingly, the drilling operation can be continuously monitored and adjusted to ensure desired directional drilling. A programmed processor may be incorporated into the drilling system to guide the drilling motor along a predetermined course. A generator assembly provides power to the processors and sensors as a result of the precessional rotation of the rotor within the stator of the drilling motor. The overall length of the drilling system is minimized by piggybacking the thrust bearings with the power generation unit and siamesing the transmission assembly for the drilling motor with the power section of the motor. As a result, a downhole drilling system of navigable length is created which can be readily directed along the desired course.
摘要:
A thermal jacket shield for a drilling motor which permits drilling operations in high temperature wells without failure of the motor. The thermal shield includes a multiple passageway casing to shroud the motor and through which is circulated drilling fluid used to operate the drilling motor. The motor is positioned within concentric inner and outer shells which form a fluid annulus through which the fluid is circulated. An intermediate housing sub connected to the lower end of the drilling motor includes a nozzle through which a controlled quantity of drilling fluid is passed into the annulus formed by the inner and outer annular shells. Outlet ports in the outer shell allow the drilling fluid to flow to the exterior of the tool. As a result, cooling fluid is continuously passed through the jacket shield to maintain the operating temperature of the motor at an acceptable temperature.