Abstract: A crosslinker composition that can produce delayed crosslinking of an aqueous solution of a crosslinkable organic polymer. The composition comprises a metal compound, preferably an organic metal complex, and most preferably an organic zirconium complex. The composition further contains an organic hydroxymonocarboxylic acid, preferably hydroxyacetic acid. The pH of the composition is preferably less than 4.8. The pH of the composition is further preferably such that when sufficient amount of composition is added to an aqueous polymer solution to result in delayed crosslinking of the polymer, the composition produces a pH in the resulting gel solution, preferably of between about 3 and about 4.5. Gel solutions produced using the composition are particularly useful in fracturing subterranean formations, and in particular in fracturing subterranean formations penetrated by an oil well in which fracturing process carbon dioxide and a proppant are added to the fracturing fluid.

Abstract: The slurries according to the invention contain: >18% NaCl; Na silicate and an agent of compatibility with magnesium consisting of H.sub.3 PO.sub.4 and HEDP diphosphonate.Thickening time is not affected by the presence or absence of salts of magnesium, up to 30% of bischofite equivalents. The rheology of the slurry and the compressive strength of the cement are also practically unaffected by magnesium contamination or the lack thereof.

Abstract: A composition and method for inhibiting the attack of aqueous corrosive fluids on metal by contacting the metal with a composition including an .alpha.,.beta.-unsaturated aldehyde and a surfactant.

Abstract: A method of packing a deviated well, particularly an oil, gas or water well. A particle/liquid slurry is injected into the wellbore, the particle density to liquid density ratio of which is no greater than about 2 to 1. The particles have a coating of adhesive on them. The particles are strained out of the slurry in the wellbore, so as to produce a packed mass of the particles adjacent the formation. The packed mass is such as to allow flow of fluids therethrough between the formation and the wellbore, while substantially preventing particulate material from the formation passing therethrough and into the wellbore. The fluid density is preferably about 0.8 to about 1.2 g/cm.sup.3.

Abstract: An improved method for inhibiting the deposition of paraffins on the surface of equipment in contact with crude oil or natural gas streams containing paraffins. The deposition of paraffins may be reduced by first contacting the equipment with a sulfur trioxide containing fluid and then adding an aqueous solution containing hydroxyl ions to the crude oil or natural gas streams containing paraffins which are in contact with the equipment.

Abstract: A lightweight cement slurry composition having a density in the range of 1.2 to 1.6, containing a solid extender agent and an SBR latex. The ratio of the liquid volume to the slurry volume should be less than 70% and preferably less than 63%. The lightweight slurry then presents a most attractive set of properties which could not be obtained previously, and in particular gas channelling is controlled.

Abstract: The invention relates in particular to measuring the delivery rate of a positive displacement pump comprising at least one piston (3) driven with reciprocating movement in a chamber (2), which chamber is connected to an inlet circuit (4) via an inlet valve (5) and to an outlet circuit (6) via a delivery valve (7). The number of cycles performed by the pump in unit time are counted, and simultaneously its volumetric efficiency is measured, thereby enabling its real delivery rate to be deduced. Its volumetric efficiency may be measured by means of position sensors (17, 18) detecting the closure and opening instants of the delivery valve, with another sensor determining the instants at which the piston (3) passes through its end positions.

Abstract: An aqueous gel containing a crosslinking agent comprising an organozirconate chelate and a rate retarding agent which delays crosslinking of the gel or a rate accelerating agent which accelerates crosslinking of the gel. The retarding agent comprises a selected aldehyde or dialdehyde. The accelerating agent comprises a member selected from a group of polyamines. In the preferred embodiment, the crosslinking agent and crosslinking rate retarder or accelerator are injected simultaneously, yet independently, into an aqueous gel while introducing the gel into a subterranean formation sought to be fractured. The viscosity of the gel increases over a period of time which is controllable by altering the quantity of rate retarding agent or accelerating agent delivered in conjunction with a fixed concentration of crosslinking agent.

Abstract: A novel buffered gelling/foaming agent and resulting gelled aqueous inorganic acid solution involving a N,N-bis (2-hydroxyethyl) fatty amine acetic acid salt (e.g., N,N-bis (2-hydroxyethyl) tallow ammonium acetate); alkali metal acetate; and acetic acid buffered system. The buffered gelling/foaming agent compositions exhibit pragmatic advantages in preparation, handling and use particularly at low temperatures because of low pour points (e.g., 5.degree.-10.degree. F.). Furthermore, the buffered gelling agent more efficiently utilizes the active ingredients in terms of desired viscosity rise as a function of concentration. The resulting gelled aqueous inorganic acid solutions using the buffered gelling agent exhibit a novel viscosity rise and calcium ion viscosity contribution as the concentrated acid is partially spent (i.e., approaches 12%), yet the totally spent acid returns to a nominal viscosity and is a foaming medium.

Abstract: Novel cementitious and non-cementitious ferrofluids are disclosed which have properties making them suitable for use in cementing wells. The cementitious fluids comprise: (a) a hydraulic cement, (b) finely divided magnetic particles, (c) a bonding agent or a surfactant, and (d) a liquid medium. The binding agent or surfactant is present in the compositions in an amount sufficient to render the compositions stable in a magnetic field. When used in cementing wells, the cementitious ferrofluids are implaced in the annulus separating a casing from the formation in a wellbore by conventional techniques and the slurry is subsequently subjected to an activating magnetic field that causes movement of the magnetic particles in the slurry. The non-cementitious ferrofluids comprise: (a) finely divided magnetic particles, (b) stabilizing agent, and (c) a liquid medium.

Abstract: Novel aqueous crosslinked gels are described herein which are useful for fracturing subterranean formations. The novel gels are comprised of a solvatable polysaccharide and a soluble zirconium crosslinking agent. The zirconium crosslinking agents are novel and are prepared by reacting a zirconium alkoxide with certain alkanolamines under anhydrous conditions. The zirconium compounds are activated by contact with water. As an example, a zirconium crosslinker was prepared by reacting zirconium tetra(n-propoxide) with triethanolamine in an n-propanol solvent under anhydrous conditions. The zirconium compound thus prepared was activated with water and used to form a stable aqueous crosslinked gel by blending the aqueous crosslinker into an aqueous hydroxypropylguar solution.

Abstract: A frangible pressure relief disc assembly is disclosed which is adapted to fit into a positive displacement pump on the suction side of each cylinder. The disc assembly provides a pressure relief when the fluid passing through the pump encounters a closed valve or other obstruction in the line. The disc assembly comprises: (a) a support member having a first side and a second side which is penetrated by a passage (e.g., a bore ) providing fluid communication from the first side to the second side, and (b) a pressure frangible disc fixedly attached to the support member and positioned to form a fluid-tight seal covering the passage.

Abstract: Various organometallic crosslinkers containing titanium or zirconium atoms in the +4 oxidation (valence) state have been used to crosslink solvatable polysaccharides (e.g., hydroxypropyl guar) in aqueous media. The crosslinked gels are useful as fracturing fluids. Aqueous solutions of the organometallic crosslinkers are stabilized against deterioration upon storage by adding an alkanolamine (e.g., triethanolamine). Additionally, the alkanolamines also stabilize the crosslinked gels against shear degradation at elevated temperatures.

Abstract: Novel aqueous crosslinked gels are described herein which are useful for fracturing subterranean formations. The novel gels are comprised of a solvatable polysaccharide and a soluble zirconium crosslinking agent. The zirconium crosslinking agents are novel and are prepared by reacting a zirconium alkoxide with certain alkanolamines under anhydrous conditions. The zirconium compounds are activated by contact with water. As an example, a zirconium crosslinker was prepared by reacting zirconium tetra(n-propoxide) with triethanolamine in an n-propanol solvent under anhydrous conditions. The zirconium compound thus prepared was activated with water and used to form a stable aqueous crosslinked gel by blending the aqueous crosslinker into an aqueous hydroxypropylguar solution.

Abstract: Aqueous chemical washes suitable for use in conjunction with well cementing operations are disclosed which comprise water, an anionic or a non-ionic surfactant (or a combination thereof) and a fluid loss control agent of the type described in U.S. Pat. No. 3,891,566.

Abstract: The machine disclosed herein is useful for blending a particle containing stream, especially a stream of solid particles, with fluids. In a typical operation, sand is mixed with a gel composition to obtain a fluid mixture suitable for stimulation treatments of oil and gas wells. The machine includes a slinger with a topside surface which may be of toroidal concave configuration. The machine also includes an impeller, of a vortex configuration, that is fastened underneath the slinger. In this machine, entrained gas is carried into the fluid phase by the particle containing stream, but the gas is then "exhausted" from the mixture through interior and exterior air exhaust channels and spaces that are built into the machine. A slinger which is particularly adapted for use in such a machine is also disclosed.

Abstract: A stage collar for stage cementing a well casing includes a slidable closing sleeve having ports alignable with ports in the stage collar case. These closing sleeve and stage collar ports communicate with an annulus around the well casing when the stage collar is open. A shift sleeve closes the ports during running in and is actuable by simple drill pipe movements to open and reclose the stage collar ports. The shift sleeve is operably coupled to the closing sleeve by a latch ring which locks the closing sleeve closed and cooperated therewith to form a smooth and substantially uniform inner stage collar bore. The drill pipe is operably connected to the stage collar by a screw-in or latch-in shifting tool which cooperates with the stage collar elements to form a fluidtight passage from the drill pipe to the annulus without entering the well casing interior. A dual stage shifting tool is also shown which permits a two-stage cementing operation to be performed with only one run down the hole.

Abstract: A method of reducing paraffin deposits on a paraffin contaminated surface. The surface is contacted with a sulphur trioxide containing liquid to react with the paraffin, and convert at least a portion of it to a water-dispersible material. The surface is also contacted with a surfactant containing or providing liquid, so as to reduce the amount of organic precipitate formed by the action of the sulphur trioxide on the paraffin. Additionally the surface is usefully rinsed with an aqueous liquid, preferably an aqueous alkaline liquid, following it being contacted with the sulphur trioxide. The surface may be contacted with the surfactant containing liquid, either prior to, or subsequent to, contacting it with the sulphur trioxide containing fluid.

Abstract: A pressurized fluid is "let-down" to atmospheric pressure as it passes through a choke assembly having two pressure orifices (choke flow beans) which are in-line and directly opposite and which are designed to deliver jet streams of generally equal force to a common in-line focal point. The choke assembly is a fixed-rate system where the volume throughput is regulated primarily by the pressure on the fluid.

Abstract: A packer and service tool assembly for oil or gas well preparation includes a disengageable coupling mechanism which permits the tool to be screwed into and out of the packer and which can be hydraulically disengaged so that the tool can be removed without applying torque to the tool or workstring. A releaseable ratchet mechanism is also provided in the packer for trapping the setting loads when the packer is set in the casing. The ratchet mechanism is releasable by pulling up a housing portion which cammingly engages collapsible ratchet fingers thereby disengaging the ratchet finger trapping teeth from a stationary ratchet ring.