Abstract: Chemical treating liquids (e.g. scale inhibitors) are dispersed in the producing interval by (a) extending a slim tube along the production tube into connection with a more rigid tube extending below a dual packer and the production tube, and (b) inflowing a mixture of gas-saturated treating liquid and gas through the slim tube.

Abstract: The present invention relates to a drill bit incorporating one or more rotary cutters. The rotary cutters are supported for rotation by a bearing assembly including ball bearings running in races in the rotary cutter and drill bit body. The bearing assembly further includes an annular bushing. A sealing assembly including an O-ring seal is provided to seal lubricant within the bearing assembly and prevent external contaminants from entering the bearing assembly. A corrosive environment has been found to increase the occurrence of stress fractures in the areas above the juncture of cutter supporting structure and the bit body. It has been found that a sacrificial anode partitioned about the surfaces of the juncture renders the surfaces cathodic and resist stress fracture.

Abstract: A mount is provided for mounting from the above surface end of a well casing or tubing string and the mount defines a vertical passage therethrough. A plurality of mounting sleeves are supported from the mount at points spaced circumferentially about the passage and the sleeves open generally radially into the passage from the outer periphery thereof. A plurality of spray heads are removably supported within the sleeves for directing spray sets of liquid outwardly from the inner ends of the sleeves and the spray jets are communicated with the interior of a manifold construction disposed exteriorly of the mount. The manifold construction includes inlet structure whereby corrosion inhibiting liquid chemicals may be supplied thereto under pressure for discharge from the spray heads.

Abstract: Method of inhibiting the precipitation of calcium carbonate from an aqueous system, comprises adding to the aqueous system a scale precipitation inhibiting amount of bis(phosphonomethylene) aminomethylene carboxylic acid.Typical aqueous systems usefully treated by the new method are water- or oil well systems, cooling water systems, steam generating systems, sea-water evaporators, hydrostatic cookers, gas-scrubbing systems, closed circuit heating systems, reverse-osmosis systems and aqueous-based refrigeration systems.

Abstract: This invention relates to a method of producing supercritical carbon dioxide from a well along with minor amounts of water having formation salts dissolved therein. Precipitation of salts carried by the formation water in the pump is prevented by continuously injecting water into the vicinity of the pump intake so as to dilute the formation water before it, or at least a portion of it, is vaporized into the water phase of the supercritical carbon dioxide. The volume of injected, substantially fresh water must be sufficient to handle the vaporization of water into the carbon dioxide in the pump as well as dilute the formation water so that the salts carried thereby remain in solution.

Abstract: This invention relates to a method of producing supercritical carbon dioxide from a well along with minor amounts of kill water having formation salts dissolved therein. The salt water is the result of killing the well with fresh water during pump installation and/or removal operations at which time the water enters the CO.sub.2 producing formation and dissolves soluble salts which come into the well when the kill water returns to the well when it is put on production. Precipitation of salts carried by the kill water in the pump is prevented by continuously injecting water into the vicinity of the pump intake so as to dilute the returning kill water before it, or at least a portion of it, is vaporized into the water phase of the supercritical carbon dioxide. The volume of injected, substantially fresh water must be sufficient to handle the vaporization of water into the carbon dioxide in the pump as well as dilute the returning kill water so that the salts carried thereby remain in solution.

Abstract: A liquid chemical, such as a corrosion inhibitor, is inserted into a producing well by pouring the chemical into an elongate carrier and then dropping the carrier into the well. The liquid chemical and the carrier are selected so that the carrier is dissolved by the chemical. The chemical is therefore delivered into the well toward the bottom thereof where it is desired to place the chemical.

Abstract: A composition is provided which, when applied to a metal surface, forms a corrosion-inhibiting film thereon. The composition comprises the reaction product of a first component selected from an epoxy resin, an epoxidized alkene and a substrate having at least one displaceable halogen, and a second component comprising a monomercaptan in a hydrocarbon diluent. The composition is applied by contacting the metal surface with the composition. The composition is particularly useful in the treatment of down-well metal surfaces in oil and gas wells to inhibit the corrosion of the metal under highly corrosive conditions, and is effective even in the presence of polymeric permeability control agents such as aqueous polyacrylamides.

Abstract: A method and apparatus for monitoring corrosive effects of fluid in a well, for use with a well tubing mandrel having a main bore and a side pocket offset from the main bore. The mandrel also has a slot along the length of the side pocket adjacent the main bore, and the exterior surface of the mandrel is free of apertures. A corrosion coupon is mounted within a notch on the side of a carrier, and the carrier is placed into the side pocket for a specified time period. The carrier is oriented to position the coupon within the slot. The carrier is then removed from the well and the coupon is inspected.

Abstract: Techniques and apparatus are described for measurement of corrosion of drill pipe in a well bore during drilling. The techniques involve the use of a test coupon attached to the external surface of a drill string. In a preferred embodiment the test coupon comprises a metal plate mounted in an insulating material such as plastic. The test coupon is preferably secured within a recess in the external surface of a sub connected between segments of a drill string.

Abstract: An electrical submersible well pump installation has a downhole secondary pump for pumping scale inhibiting chemicals below the downhole pumping assembly. The downhole pumping assembly includes a centrifugal primary pump driven by an electrical motor located below the pump and separated by a seal section for preventing well fluids from entering the motor. The secondary pump is also driven by the motor and is located between the seal section and the primary pump. The secondary pump has an intake connected to a tube that extends upwardly above the intake of the primary pump. The secondary pump has a discharge port connected to a discharge tube that extends downwardly to a point below the motor. Chemicals introduced at the surface into the annulus flow downwardly into the intake of the secondary pump and are discharged below the motor. The secondary pump has an inverted impeller and diffuser that have a discharge on the lower end for discharging fluids downwardly.

Abstract: A method is disclosed for inhibiting silica dissolution during steam injection into a formation. In the method, there is added to the steam, or to feedwater used to generate the steam, a mixture comprising:(a) a compound selected from the group consisting of ammonium salts of inorganic acids, ammonium salts of carboxylic acids, quaternary ammonium halides, amine or substituted amine hydrochlorides, and mixtures thereof; and(b) a compound selected from the group consisting of ammonia, salts which decompose in steam to form acid neutralizers or buffers having alkaline pH values, amides of carbamic acid or thiocarbamic acid and derivatives of such amides, tertiary carboxylic acid amides and their substituted and alkylated derivatives, and mixtures thereof.In steam, the compound of (a) decomposes to form a proton, which neutralizes hydroxide generated by ions in the steam generator feedwater.

Abstract: Method and apparatus for use in drilling a well from a floating vessel by means of a riser, which connects the vessels drilling equipment to a wellhead assembly adjacent the ocean floor. The riser is capable of being disconnected from the wellhead assembly, and having its upper end locked to the vessel. The present riser locking apparatus is made up of selectively-positionable resiliently-moveable locking beams adapted to be remotely actuated to lock the upper elements of the riser to the vessel, thereby preventing lateral or vertical movement of the riser relative to the vessel.

Abstract: A composition comprising the reaction adduct or neutralized product resulting from the reaction of a maleic anhydride and an oil containing a polynuclear aromatic compound is provided which, when applied to a metal surface, forms a corrosion-inhibiting film thereon. The composition is particularly useful in the treatment of down-hole metal surfaces in oil and gas wells to inhibit the corrosion of the metal.

Abstract: The present invention relates to a process for scavenging hydrogen sulfide which frequently becomes entrained in drilling fluid during the course of drilling operations through subterranean formations. The process consists of introducing a solid oxidant in powdered form into the circulating drilling fluid when hydrogen sulfide is encountered. The solid oxidants are selected from the group consisting of calcium hypochlorite (Ca(OCl).sub.2), sodium perborate (NaBO.sub.3), potassium permanganate (KMnO.sub.4), and potassium peroxydisulfate (K.sub.2 S.sub.2 O.sub.8). The solid oxidants are soluble in the drilling fluid, promoting fast and complete scavenging reactions without adversely altering the drilling fluid rheology.

Abstract: Flow-restricting materials containing epoxy resins present in a well treated with an epoxy resin, for the purpose of coating and consolidating unconsolidated sand adjacent the well and/or gravel packing in the well, or of coating metallic equipment in the well, to prevent corrosion or the deposition of organic or inorganic solids on the equipment, by contacting the flow-restricting material with a solvent composition, comprising, N-methyl-2-pyrrolidone and a diluent in an amount of 0 to 80% by wt., for a time sufficient to form a flowable fluid and removing the flowable fluid from the well. Combination well treatments include consolidating sand and/or gravel in a well or coating metallic equipment in the well with an epoxy resin and, thereafter, subjecting the treated well to the above solvent treatment to remove flow-restricting materials from the well.

Abstract: A method is disclosed for controlling the deposition of metal-containing scales, such as iron silicate scale, from a hot, aqueous, geothermal brine or the like, without substantial corrosion of brine handling equipment. The brine is contacted with (1) an amount of an acid sufficient to reduce the pH of the brine between 0.1 and 0.5 unit and (2) a greater than stoichiometric amount of a reducing agent for reducing trivalent iron and manganese cations in a high temperature brine solution to divalent ions. An overall decrease in scale deposition, especially of iron silicate scale, is achieved while a silver-rich scale can be recovered from silver-containing brines.

Abstract: A gravity system, the only moving parts of which are the valves, uses only the system pressures, and opening and closing of valves to feed treatment liquids to an oil well. The chemical treatment liquid is stored in a drum above a volume chamber. The volume chamber has five lines connected to it, each with a valve. A feed line with a feed valve connects the volume chamber to the treatment drum. A vent line with a vent valve vents the top part of the volume chamber to the atmosphere. A liquid pressure line with a pressure valve connects the flow line (connected to the oil well eduction tube) to the volume chamber. A flush line with a flush valve connects the bottom of the volume chamber to the well annulus. A gas line with a gas valve connects the volume chamber to the annulus. When the vent valve and feed valve are open and all other valves are closed, the volume chamber will fill with liquid by gravity from the chemicals within the treatment drum.