摘要:
An apparatus and method for removing cuttings in a deviated borehole using drilling fluids. The apparatus includes a pipe string and a bottom hole assembly having a down hole motor and bit for drilling the borehole. The pipe string has one end attached to the bottom hole assembly and does not rotate during drilling. The apparatus and methods raise at least a portion of the pipe string in the deviated borehole to remove cuttings from underneath the pipe string portion.
摘要:
A subsea subterranean well completion has a tubing string with a portion that extends through a region of the completion exposed to temperatures sufficiently low to potentially create wax and/or hydrate deposits within the tubing string during pre-production or shut-down periods. In order to inhibit or remove the formation of these deposits, the well completion is provided with a flow assurance system operative to create a flow of heating fluid which is recirculated through the space between the tubing string portion and the well casing/production riser structure in a manner causing the heating fluid to flow along the outer side of the tubing string portion without previously or subsequently traversing the interior of the tubing string. The heat absorbed by the tubing string inhibits or removes wax and/or hydrate formation in production fluid therein without the previous necessity of using a chemical injection system to inject plug-inhibiting chemicals into the interior of the tubing string. The flow assurance system may also be used to recirculate or otherwise flow other contact fluids, such as corrosion inhibiting fluids or insulation blanket fluids, against the outer side of the tubing string.
摘要:
A method for drilling a wellbore in a formation using a drilling fluid, wherein the drilling fluid has a first temperature, and wherein the wellbore has a first wellbore depth. In one embodiment, the method comprises determining at least one fracture gradient, wherein the fracture gradient is determined at about the first wellbore depth; increasing the temperature of the drilling fluid from the first temperature to a desired temperature at about the first wellbore depth; drilling into the formation at increasing wellbore depths below the first wellbore depth, wherein at least one equivalent circulating density of the drilling fluid is determined at about the first wellbore depth; and setting a casing string at a depth at which the equivalent circulating density is about equal to or within a desired range of the fracture gradient. In other embodiments, an automated system is used to maintain the temperature of the drilling fluid at about first wellbore depth.