Abstract: The present disclosure provides an ultra-high temperature resistant cement slurry system for cementing and the preparation method and use thereof. The cement slurry system comprises cement, an ultra-high temperature strength stabilizer, an ultra-high temperature reinforcing material, a density regulator, an ultra-high temperature suspension stabilizer, a dispersant, a fluid loss additive, a retarder, a defoaming agent and water, wherein the ultra-high temperature suspension stabilizer comprises an ether-based starch, an aluminosilicate and a polyalcohol polymer. The method for preparing the cement slurry system includes dry mixing and wet mixing raw materials homogeneously, respectively, and then homogeneously mixing the dry mix and wet mix to obtain the cement slurry system. The present disclosure further provides use of the cement slurry system for cementing in deep wells and ultra-deep wells at high and ultra-high temperatures.

Abstract: The present disclosure relates to the technical field of oil and gas field exploitation, in particular to an early strength material suitable for a cement slurry system, a cement slurry composition, a cement slurry system, a preparation method therefor and the use thereof. The early strength material contains an aluminum salt, a sodium salt, crystal whiskers, an inorganic mineral and dispersing agent I, wherein the weight ratio of the aluminum salt, the sodium salt, the crystal whiskers, the inorganic mineral and dispersing agent I is (1-3):(1-3):(1-4):(1-8):1.

Abstract: A well cementing method is described for improving cementing quality by controlling the hydration heat of cement slurry. By controlling the degree and/or rate of hydration heat release from cement slurry, the method improves the hydration heat release during formation of cement with curing of cement slurry, improves the binding quality between the cement and the interfaces, and in turn improves the cementing quality at the open hole section and/or the overlap section. The cementing method improves cementing quality of oil and gas wells and reduces the risk of annular pressure.

Abstract: An apparatus and method for determining a volume stability of well cement including a reaction kettle, a radial contraction, an expansion ring, a heater, a pressurizer, and a volume change parameter tester. The radial contraction and expansion ring include a first casing and a second casing, the first casing is a casing made of elastic material, the second casing is a steel casing, and the first casing sheathes the second casing. The heater and the pressurizer are used to provide a preset temperature and a preset pressure respectively and the volume change parameter tester is used to detect a radial volume change parameter of the well cement. The apparatus is provided with the radial contraction and expansion ring to acquire the radial volume change parameter of the well cement, and comprehensively evaluates the volume stability of the well cement using the radial volume change parameter of the well cement.

Abstract: The invention provides a method and device for measuring the elasticity of hardened cement for cementing of oil-gas wells. The measurement method comprises: determining the loading and unloading rates of the hardened cement; determining the maximum loading on the hardened cement; determining the experimental temperature and the experimental pressure of the hardened cement; establishing a stress-strain curve for the hardened cement; and describing the elasticity of the hardened cement with the degree of strain recovery of the hardened cement in different cycles, and describing the mechanic integrity of the hardened cement with the degree of damage to the hardened cement in different cycles. The invention further provides a device for measuring the elasticity of hardened cement for cementing of oil-gas wells.

Abstract: A well cementing method is described for improving cementing quality by controlling the hydration heat of cement slurry. By controlling the degree and/or rate of hydration heat release from cement slurry, the method improves the hydration heat release during formation of cement with curing of cement slurry, improves the binding quality between the cement and the interfaces, and in turn improves the cementing quality at the open hole section and/or the overlap section. The cementing method improves cementing quality of oil and gas wells and reduces the risk of annular pressure.

Abstract: An apparatus and method for determining a volume stability of well cement including a reaction kettle, a radial contraction, an expansion ring, a heater, a pressurizer, and a volume change parameter tester. The radial contraction and expansion ring include a first casing and a second casing, the first casing is a casing made of elastic material, the second casing is a steel casing, and the first casing sheathes the second casing. The heater and the pressurizer are used to provide a preset temperature and a preset pressure respectively and the volume change parameter tester is used to detect a radial volume change parameter of the well cement. The apparatus is provided with the radial contraction and expansion ring to acquire the radial volume change parameter of the well cement, and comprehensively evaluates the volume stability of the well cement using the radial volume change parameter of the well cement.

Abstract: The invention provides a method and device for measuring the elasticity of hardened cement for cementing of oil-gas wells. The measurement method comprises: determining the loading and unloading rates of the hardened cement; determining the maximum loading on the hardened cement; determining the experimental temperature and the experimental pressure of the hardened cement; establishing a stress-strain curve for the hardened cement; and describing the elasticity of the hardened cement with the degree of strain recovery of the hardened cement in different cycles, and describing the mechanic integrity of the hardened cement with the degree of damage to the hardened cement in different cycles. The invention further provides a device for measuring the elasticity of hardened cement for cementing of oil-gas wells.