A method in which a stream of dry cementitious powder passes through a first conduit and aqueous medium stream passes through a second conduit to feed a slurry mixer to make cementitious slurry. The cementitious slurry passes through a third conduit and a reinforcement fiber stream passes through a fourth conduit to feed a fiber-slurry mixer which mixes the slurry and discrete fibers to make a stream of fiber-slurry mixture. An apparatus for performing the method is also disclosed.

Methods and apparatus for controlling a characteristic of a cement slurry at a cementing unit, including regulating a characteristic of the cement slurry employing a closed loop feedback arrangement in the cementing unit, and adjusting a gain of the closed loop feedback arrangement in response to sampling an error of the characteristic.

Embodiments disclosed provide a pump assembly including a first pump for delivering at least one fluid. The first pump may include a first inlet coupled to the first pump for delivering at least one first fluid to the first pump, a second inlet coupled to the first pump for delivering at least one second fluid to the first pump, a first discharge coupled to the first pump for delivering the at least one first fluid at a first pressure, and a second discharge coupled to the first pump for delivering the at least one second fluid at a second pressure. In some embodiments, the first discharge and the second discharge are isolated from each other.

An all-in-one mobile wellsite service unit for providing equipment and services at an oil and gas well related to well abandonment is provided. The mobile unit comprises a water storage tank, at least one cement mixing barrel for mixing a cement slurry, a progressive cavity pump for pumping the cement slurry, and a hydraulic hose for connecting to a hydraulic power source to provide power to the cement mixing barrel and the progressive cavity pump. The mobile unit may also contain downhole tools needed for well abandonment, including a well cleaning tool, a cementing tool, a hydraulic packer, and more.

Methods of wellbore cementing are provided. A method of designing a cement composition may include: selecting a target heat of hydration for a target time and temperature; selecting one or more cementitious components and a weight percent for each of the one or more cementitious components such that a sum of a heat of hydration of the one or more cementitious components is less than or equal to the target heat of hydration; preparing the cement composition; and allowing the cement composition to set.

Methods of wellbore cementing are provided. A method of designing a cement composition may include: selecting a target heat of hydration for a target time and temperature; selecting one or more cementitious components and a weight percent for each of the one or more cementitious components such that a sum of a heat of hydration of the one or more cementitious components is less than or equal to the target heat of hydration; preparing the cement composition; and allowing the cement composition to set.

An all-in-one mobile wellsite service unit for providing equipment and services at an oil and gas well related to well abandonment is provided. The mobile unit comprises a water storage tank, at least one cement mixing barrel for mixing a cement slurry, a progressive cavity pump for pumping the cement slurry, and a hydraulic hose for connecting to a hydraulic power source to provide power to the cement mixing barrel and the progressive cavity pump. The mobile unit may also contain downhole tools needed for well abandonment, including a well cleaning tool, a cementing tool, a hydraulic packer, and more.

A bulk storage plant for providing cement mixtures oil well construction is disclosed. The bulk storage plant includes bulk storage sources, an additive station, a weigh batcher, and a tumble blender. The bulk storage sources are adapted to contain cement ingredients. The additive station is adapted to provide an additive for adjusting cement properties. The weigh batcher is connected to the bulk storage silos and the additive station. The weigh batcher is adapted to receive the cement ingredients from the bulk storage sources and the additive from the additive station. The tumble blender is connected to the weigh batcher and is adapted to receive the cement ingredients and the additive from the weigh batcher. The tumble blender is adapted to blend the ingredients and provide the blended ingredients to one of a temporary storage silo and a storage vessel for transport to the oil well site.

A mobile aggregate hopper for a volumetric and gravimetric mixer having arcuate longitudinal walls for holding and isolating aggregate. The mobile aggregate hopper has a base integral with the arcuate longitudinal walls with an aggregate transfer conveyor and means for attachment to a trailer or chassis having wheels. The single sheet structure of the longitudinal arcuate side walls minimizes welding and mechanical joints during manufacturing and provides a hopper with high strength and capacity and low overall weight.

A technique facilitates mixing of cement slurry for use in a cementing application. At least one cement mixer is provided with a tank, e.g. a conical tank, having a powder cement blend inlet and a mixing liquid inlet. A cement slurry discharge may be positioned generally beneath the tank. A mixing assembly also is positioned below the tank and driven by a shaft. The mixing assembly is exposed to an interior of the tank and is used to mix the cement slurry when rotated by the shaft and to direct the cement slurry out through the cement slurry discharge. Additionally, a recirculation system comprises an inlet positioned to receive a portion of the cement slurry mixed in the mixing assembly. The recirculation system also comprises an outlet positioned to direct the portion back into the mixer to enhance mixing effects.