The foundry sand binder supply apparatus of the present invention comprises a hopper for storing a binder therein, a binder transfer device for transferring the binder, a binder measuring and discharging device disposed beneath a distal end of the binder transfer device, and a binder supply amount control device. The binder measuring and discharging device comprises a measuring container for receiving the binder therein, a load cell for measuring the weight of the binder inside the measuring container, and a discharge device for discharging the binder from the measuring container. The binder supply amount control device is operable to control the discharge device to discharge the binder from the measuring container by a predetermined amount less than the whole amount of the binder inside the measuring container, and control the binder transfer device to supply the binder into the measuring container by the predetermined amount of the discharged binder.

An object is to accurately estimate loss-on-ignition in a short time. A loss-on-ignition estimation apparatus includes at least one processor configured to carry out an estimation step, the estimation step including estimating the loss-on-ignition of foundry sand with use of a learned model constructed by means of machine learning. The learned model is configured to receive, as input, (1) sand weight data relating to a weight of the foundry sand detected in a calcination period and (2) at least one of (i) sand property data relating to one or more properties of the foundry sand, (ii) additive data relating to one or more additives added to the foundry sand, and (iii) calcination environment data relating to a calcination environment detected in the calcination period. The learned model is configured to generate, as output, an estimated loss-on-ignition of the foundry sand.

A method of reusing core sand includes: crushing a core used for casting into granules; heating the granules at a temperature of 300 C. to 550 C.; causing the heated granules to collide against each other such that water glass used as a binder detaches from the core sand; and blowing air into a mixture of the water glass and the core sand, which are detached from each other, such that the core sand is separated and collected from the mixture due to a difference in specific gravity between the water glass and the core sand.

A continuous mixing apparatus for a powder/granular material and a viscous liquid, with a mixing cylinder, a shaft member which is on a central axis of the mixing cylinder and rotates inside the mixing cylinder, and a plurality of mixing paddles disposed on a surface of the shaft member, wherein the mixing cylinder is with a powder/granular material feed port on one end portion, a mixed material discharge port on the other end portion, and a viscous liquid injection unit between the powder/granular material feed port and the mixed material discharge port, and the plurality of mixing paddles are disposed on the shaft member so as to form a spiral around the central axis, the plurality of mixing paddles being, in at least a portion between the viscous liquid injection unit and the mixed material discharge port, attached to provide first rows having an attachment angle of 5 to 60.

A method of reusing core sand includes crushing a core used for casting into granules; heating the granules at a temperature of 300 C. to 550 C.; causing the heated granules to collide against each other such that water glass used as a binder detaches from the core sand; and blowing air into a mixture of the water glass and the core sand, which are detached from each other, such that the core sand is separated and collected from the mixture due to a difference in specific gravity between the water glass and the core sand.

A method of reusing core sand includes: crushing a core used for casting into granules; heating the granules at a temperature of 300 C. to 550 C.; causing the heated granules to collide against each other such that water glass used as a binder detaches from the core sand; and blowing air into a mixture of the water glass and the core sand, which are detached from each other, such that the core sand is separated and collected from the mixture due to a difference in specific gravity between the water glass and the core sand.

A sand core making machine that includes a hopper having a hollow body with an inner surface delimiting a passageway for a material used in the manufacture of a sand core. The hopper includes a plurality of breaker assemblies with each breaker assembly having at least one string. The ends of a string are attached to corresponding attachment points of the inner surface of the hollow body, such that the strings are arranged in a flow passage of the material. At least two breaker assemblies are spaced apart such that the two breaker assemblies interact with each other to break lumps of the material supplied to the hopper when the hollow body is shaken.