Anti-bit balling drilling fluids and methods of making and using drilling fluids are provided. The anti-bit balling drilling fluid contains water, a clay-based component, and at least one of a surfactant having the formula: R(OC.sub.2H.sub.4).sub.xOH, where R is a hydrocarbyl group having from 10 to 20 carbon atoms and x is an integer from 1 and 10, or a polyethylene glycol having the formula: H(OCH.sub.2CH.sub.2).sub.nOH, where n is an integer from 1 to 50. Methods of making and using these drilling fluids are also provided.

Drilling fluids and methods of making and using drilling fluids are provided. The drilling fluid contains an aqueous phase, an oleaginous phase, and at least one surfactant having the formula R(OC.sub.2H.sub.4).sub.xOH, where R is a hydrocarbyl group having from 8 to 20 carbon atoms and x is an integer from 1 to 10. Methods of producing drilling fluids include mixing an aqueous phase, an oleaginous phase, and at least one surfactant, and shearing the mixture. Methods of using drilling fluids to drill subterranean formations include mixing an aqueous phase, an oleaginous phase, and at least one surfactant to produce a mixture, which is sheared to form a drilling fluid, and pumped through a drill string in a drill bit located in a subterranean formation. Rock cuttings are transported from the drill bit to a surface of the subterranean formation and the drilling fluid is circulated in the subterranean formation.

Drilling fluid compositions include invert emulsion fluids having an oleaginous phase, an aqueous phase, and an emulsifier composition that includes an ethoxylated alcohol compound and a polyaminated fatty acid compound. The ethoxylated alcohol compound has the formula R.sup.1(OCH.sub.2CH.sub.2).sub.nOH, where R.sup.1 is a hydrocarbyl group having from 8 to 22 carbon atoms and n is from 1 to 8. The ethoxylated alcohol compound has a Hydrophilic-Lipophilic Balance (HLB) of less than or equal to 6. The polyaminated fatty acid compound has the formula R.sup.2CONHCH.sub.2CH.sub.2N(COR.sup.2)CH.sub.2CH.sub.2NHCOR.sup.3, where R.sup.2 is a hydrocarbyl group having from 1 to 20 carbon atoms and R.sup.3 is a hydrocarbyl group having 1 to 10 carbon atoms or an alkylene carboxylate group having formula R.sup.4COOH, where R.sup.4 is a saturated or unsaturated hydrocarbylene having from 1 to 10 carbon atoms. Methods of drilling wells include operating a drill in a wellbore in the presence of drilling fluid compositions.

A drilling fluid composition which includes a base fluid, one or more additives, and a viscosifier package. The base fluid is an invert emulsion comprising oil and water. Further, the one or more additives is chosen from an emulsifier, a weighting material, a fluid-loss control additive, or an alkaline compound. The viscosifier package includes a fatty acid having 6 or more carbon atoms and an aliphatic polyester. The drilling fluid composition has a yield point of from 30 lb.sub.f/100 ft.sup.2 to 100 lb.sub.f/100 ft.sup.2 and a low shear yield point of from 10 lb.sub.f/100 ft.sup.2 to 40 lb.sub.f/100 ft.sup.2. The associated method of drilling a subterranean well including operating a drill in a wellbore in the presence of the drilling fluid composition is also provided.

Spacer fluids include an emulsion, a surfactant package, and at least one additive that modifies the rheology of the spacer fluid, the density of the spacer fluid, or both. The emulsion may include an aqueous external phase and a hydrocarbon-based internal phase. The surfactant package may include one or more surfactants. The surfactant package may also include a surfactant having the general structure R(OCH.sub.2CH.sub.2).sub.9OH, where R is a hydrocarbyl having 12 carbon atoms, 13 carbon atoms, or 14 carbon atoms. The spacer fluid may contain at least 4.25 pounds of R(OCH.sub.2CH.sub.2).sub.9OH per barrel of the spacer fluid.

According to at least one embodiment of the present disclosure, a well bore cementing system may comprise a spacer fluid and a cement slurry. The spacer fluid may be positioned within a well bore, and the spacer fluid may comprise a first surfactant package comprising one or more surfactants. The cement slurry may be positioned within the well bore, and the cement slurry may comprise a second surfactant package comprising one or more surfactants.

In one embodiment, a spacer fluid may comprise a base fluid and a surfactant package. The surfactant package may comprise one or more surfactants, where the surfactant package comprises a first surfactant having the chemical structure R(OC.sub.2H.sub.4).sub.xOH. R may be a hydrocarbyl group having from 9 to 20 carbon atom, and x may be an integer from 5 and 15. The first surfactant may have a hydrophilic-lipophilic balance (HLB) of from 12 to 13.5.

In one embodiment, a retarded acid system comprises an aqueous acid and a retarding surfactant. The aqueous acid may comprise from 5 wt. % to 25 wt. % of a strong acid, that is, an acid having a K.sub.a greater than or equal to 0.01. The aqueous acid may further comprise from 75 wt. % to 95 wt. % water. The retarding surfactant may have the general chemical formula R(OC.sub.2H.sub.4).sub.xOH where R is a hydrocarbon having from 11 to 15 carbon atoms and x is an integer from 6 to 10. The retarding surfactant may have a hydrophilic-lipophilic balance from 8 to 16.

Dispersions are prepared by dispersing a polymer precursor such as a polyol into a non-aqueous fluid. The resulting droplets of the polymer precursor is partially polymerized to produce liquid or partially gelled droplets, and then sized to a target particle size. The sized particles are then cured to form solid particles. The process allows for close control of particle size, allows for good control of temperature, and is amenable to batch, semi-continuous or even continuous operation. The resulting dispersions are useful as electrorheological fluids.

A method of manufacturing an overbased calcium sulfonate grease comprising a reduced amount of overbased calcium sulfonate, water and at least one non-aqueous converting agent, where at least a portion of the non-aqueous converting agent is added after one or more delay periods relative to the addition of the water. A delay period may involve the period of time it takes to adjust the temperature of the mixture, a period of time during which the mixture is held at a temperature or within a range of temperatures, and multiples and any combination thereof. These calcium sulfonate greases have improved thickener yield and high dropping points compared to greases of substantially similar composition made without a delay between the additions of water and a non-aqueous converting agent, particularly when a poor quality overbased calcium sulfonate is used.