Abstract: A well liner for a subterranean well is provided comprising an elongated tubular member which may be a wire wrapped screen having a plurality of slots or passages which are disposed longitudinally and circumferentially of and extending from the outer surface to the inner surface of the tubular member, and an impermeable inorganic matrix substantially filling said slots or passages and coated upon said inner and outer surfaces, said matrix being the reaction product of a first reactant consisting essentially of magnesium oxide and a second reactant consisting essentially of magnesium chloride, in a solvent or solution therefor.

Abstract: Methods for cleaning sand from a helical spring sand screen for use at the petroliferous unconsolidated sand strata of an oil well are the basic steps: (1) ceasing flow from the production tube, (2) injecting high pressure liquid into a reciprocal valve means for expanding the helical spring sand screen, and (3) injecting more high pressure liquid into the helical spring sand screen for cleaning thereof. Then upon ceasing of flow of the high pressure liquid, the stored energy in another spring contracts the helical spring sand screen for restoring production of sand-free oil from the production tube. A second modification is disclosed.

Abstract: Wellhead flow control apparatus for controlling the flow of fluids from a well producing fluids and debris including a novel device for separating and accumulating the debris. The device comprises an outer shell defining an enclosed accumulation chamber, a perforated outlet conduit communicating with the chamber to allow the passage of fluids but prevent passage of debris, and access means to facilitate periodic removal of the accumulated debris. The wellhead apparatus is especially useful for flow control of fluids from geothermal steam wells.

Abstract: An apparatus is disclosed for packing the annular space between the exterior of a sand screen or liner and the well casing or bore with accurately sized sand or gravel to prevent the intrusion of well sands into the well casing or bore. The apparatus includes a hydraulically actuated fluid diverting means and release mechanism to open diverting passageways and separate the sand screen or liner assembly from the run-in tool before introduction of the sized sand or gravel and without rotation of the run-in tool with respect to the sand screen or liner. The diverting means is capable of being closed at the completion of the injection process to facilitate the resumption of production from the well without the necessity of pulling the assembly out of the well bore for closing the diverting means thereby providing a novel method for gravel packing or sand packing a well.

Abstract: A method and assembly adapted to extract petroleum from a bore hole or well and particularly using steam to release the petroleum from the surrounding underground. These method and assembly include the release of steam at the bottom of a tube section and extraction of petroleum above the steam outlet to provide simple and efficient assembly and method, which allow for simultaneous feeding of steam and pumping out of petroleum. The assembly includes coaxial tube sections wherein steam pipes are placed in the annular space between the tube sections to outwardly feed steam at the bottom of the latter while defining a central passage for pumping the petroleum therefrom.

Abstract: A wellpoint having an outer screen pipe, and an inner intake pipe connected to a vacuum source. A positionable valve is mounted between the screen pipe and the intake pipe to regulate the amount of screen pipe surface subject to vacuum by the intake pipe.