Abstract: A system for forming a cementitous slurry comprising at least water or other liquid and at least one flowable particulate mass such as sand or cement has computerized control of loading the ingredients into a mixing chamber. The mixing chamber has a scale that provides a signal indicating the current weight of the mixing chamber. The computer monitors the weight of the mixing chamber as these ingredients are individually loaded into the mixing chamber. When the desired weight of a particular ingredient has been loaded, the computer halts the delivery of that ingredient. Ingredients are loaded first at a relatively high rate, and then as the desired weight of material in the mixing chamber approaches, the rate slows.

Abstract: A portable cement mixing system uses ingredients such as cement, water and sand in predetermined quantities. A digital controller coordinates all of the operating elements of the apparatus for the entire mixing process and stores mixing programs relative to the mixing process for a variety of cements which includes the various ingredient quantities. Separate storage containers each coupled to a conveyors from the container extend to a mixer to transfer that quantity to the mixer for each cement ingredient. The conveyors are operated in sequence by the controller to load the mixer with a predetermined quantity of each of the required ingredients prior to mixing. The mixer and its contents are weighed before and during the transfer of each ingredient to precisely determine and transfer the required amount of each ingredient. After the mixer is loaded with all of the ingredients, the mixer is operated for a predetermined length of time.

Abstract: Apparatus and methods for simultaneously testing molten metal, such as steel, for concentration of three or more dissolved gases. A gas flow manifold allows multiple calibrations of a gas analysis device independently of operations such as immersion and purging of an immersible probe that can be provided with a bypass conduit for gas flow directly to the analysis device. Accurate nitrogen content is determined by oxidizing a retrieved gas sample using heated CuO and measuring gas concentration of the gas before and after such oxidation. A gas reservoir can be used to temporarily store a portion of the retrieved gas for use in such testing.