Abstract: Bonded aggregate compositions such as concrete, concrete repair products, high temperature refractories, high temperature insulation and fire resistant insulation are made from an aqueous solution of phosphoric acid and a separate, storable dry mixture of suitable aggregate, monocalcium phosphate, and calcium in the form of calcium aluminate cement or calcium oxide. The proportion of wet to dry constituents is variable so as to select the working time and strength of the aggregate composition, typically on the order of ten to fifteen minutes. The mixture of the preferred dry constituents, and the binder to be mixed with the aggregate to yield the preferred dry mixture, are also disclosed.

Abstract: Bonded aggregate compositions such as concrete, concrete repair products, high temperature refractories, high temperature insulation and fire resistant insulation are made from an aqueous solution of phosphoric acid and a separate, storable dry mixture of suitable aggregate, monocalcium phosphate, and calcium in the form of calcium aluminate cement or calcium oxide. The proportion of wet to dry constituents is variable so as to select the working time and strength of the aggregate composition, typically on the order of ten to fifteen minutes. The mixture of the preferred dry constituents, and the binder to be mixed with the aggregate to yield the preferred dry mixture, are also disclosed.

Abstract: The invention is concerned with controlling weldpool penetration during root pass welding in an open butt joint defined in a workpiece to be welded by a welding torch with a welding wire being continuously fed from the welding torch to the joint to form a weldpool penetrating the joint, the workpiece and welding torch being movable relative to one another. A visual sensor is positioned ahead of the welding torch and in alignment with the joint for frontly viewing the weldpool at an angle of about 10.degree. to about 20.degree. relative to a line tangent to the workpiece at the weldpool, to thereby provide a full image of the weldpool defining a weldpool contour line, the sensor and welding torch being disposed on a common side relative to the workpiece.

Abstract: A method and a device for sampling a radiation field emitted from an X-ray machine for determining certain operational characteristics of the machine. A cassette container is disposed at a predetermined position relative to a radiation field of the X-ray machine. The cassette container houses a removable holder containing one or more thermo-luminiscent crystals associated with a respective one or more crystal filters supported in the container. The filters have different densities from one another.

Abstract: Bonded aggregate compositions such as concrete, concrete repair products, high temperature refractories, high temperature insulation and fire resistant insulation are made from an aqueous solution of phosphoric acid and a separate, storable dry mixture of suitable aggregate, monocalcium phosphate, and calcium in the form of calcium aluminate cement or calcium oxide. The proportion of wet to dry constituents is variable so as to select the working time and strength of the aggregate composition, typically on the order of ten to fifteen minutes. The mixture of the preferred dry constituents, and the binder to be mixed with the aggregate to yield the preferred dry mixture, are also disclosed.