A coating method of a board for producing a concrete product and a board coated by the same are proposed. The coating method is advantageous in that the whole surface of a board can be rapidly coated and dried to prevent surface corrosion of the board and to prevent further corrosion on a damaged surface of the board, thus improving the durability of the board and the quality of the produced concrete products. The coating method includes: removing residues existing on an outer surface of the board by blowing high-pressure air to an upper surface and a lower surface of the board for producing a concrete product; coating by spraying coating liquid to the outer surface of the board from which the residues have been removed; and drying the coating liquid by blowing high-pressure air to the outer surface of the board.

A method and device for producing lightweight panels with a core of gypsum or of cement and gypsum, with pores for decreasing volumetric weight, and with a covering made of cardboard or of a sheet of glass fibers. The production line does not change except for the addition of a device which forms closed hollow cavities within a suspension in an area where an upper sheet covers the suspension. Air pressure which is fed into the formed cavities is slightly higher than the hydraulic pressure of the suspension, so as to prevent the gaps being filled by the suspension. The layers are less thick, and the type and dimensions of the cavities and the thickness of the walls are varied depending on the desired qualities of the panels.

To provide a building material manufacturing apparatus that is suitable for suppressing clogging of a screen that screens a building raw material.

A building material manufacturing apparatus X1 includes at least a screen part 10 and a cleaning mechanism part 40. The screen part 10 includes at least one screen sheet 12 that has an inclination and that has a screen mesh. The cleaning mechanism part 40 includes a scraping part 40a. When the apparatus operates in a building material manufacturing mode in which a building raw material M is supplied to the screen sheet 12 and the screen sheet 12 is performing a wave motion, the scraping part 40a is separated from the screen sheet 12, and, when the apparatus operates in a cleaning mode in which the building raw material M is not supplied to the screen sheet 12 and the screen sheet 12 is not performing a wave motion, the scraping part 40a rotates in contact with the screen sheet 12.

An automated system and associated method of producing manhole products includes an area closed production loop where molds are moved to discrete workstations. A standard set of tasks (e.g., mold cleaning and release agent application, reinforcement placement, pre-pouring activities and inspection, filling, curing, and product demolding) are performed at various ones of the workstations. Once one of these tasks is completed, the mold moves to the next workstation. This enables a transition from ‘cast on the floor’ method to an assembly line principle.

The present disclosure relates to a method of forming a waffle slab with concrete surfaces that do not require polishing, the method comprising: providing steel molds connected to each other, and forming a space in the steel molds, wherein at least one of the steel molds has a hole; disposing a plurality of inner molds in the space formed by the steel molds; disposing predetermined steel bar cages between the plurality of inner molds, and between the plurality of inner molds and the steel molds; disposing a steel plate on top surfaces of the steel molds, wherein the steel plate comprises separate air holes; and pouring a Self-Compacting Concrete (SCC) into the space from the hole of the at least one of the steel molds such that the SCC fills the space to form the waffle slab.

A method of cleaning concrete forms includes preparing a liquid comprising a mixture of water and a chemical, and heating the liquid to a temperature of about 180 degrees Fahrenheit. The concrete form is placed into the liquid, and an ultrasonic pressure wave is imparted into the liquid in the tank using an ultrasonic transducer powered by a generator.

A coating method of a board for producing a concrete product and a board coated by the same are proposed. The coating method is advantageous in that the whole surface of a board can be rapidly coated and dried to prevent surface corrosion of the board and to prevent further corrosion on a damaged surface of the board, thus improving the durability of the board and the quality of the produced concrete products. The coating method includes: removing residues existing on an outer surface of the board by blowing high-pressure air to an upper surface and a lower surface of the board for producing a concrete product; coating by spraying coating liquid to the outer surface of the board from which the residues have been removed; and drying the coating liquid by blowing high-pressure air to the outer surface of the board.

The present disclosure relates to a method of forming a waffle slab with concrete surfaces that do not require polishing, the method comprising: providing steel molds connected to each other, and forming a space in the steel molds, wherein at least one of the steel molds has a hole; disposing a plurality of inner molds in the space formed by the steel molds; disposing predetermined steel bar cages between the plurality of inner molds, and between the plurality of inner molds and the steel molds; disposing a steel plate on top surfaces of the steel molds, wherein the steel plate comprises separate air holes; and pouring a Self-Compacting Concrete (SCC) into the space from the hole of the at least one of the steel molds such that the SCC fills the space to form the waffle slab.

A die apparatus capable of removing powder adhering to cut surfaces so as to securely form a cavity in a desired shape includes divided dies reciprocatingly driven by sliders to comes into contact with one another so as to form a cavity. Punches are inserted into the cavity from above and below the cavity. Each divided die is provided with cut surfaces that come into contact with the other divided dies. A gas passage connected to a gas injection port that injects gas from the cut surface is formed in each divided die.

A dry-cast concrete block is provided. The dry-cast concrete block comprises a surface to be exposed, at least a portion of the surface having a cast texture with a natural stone appearance. The cast texture may have a surface level difference of greater than 4 mm. In one example of implementation, the dry-cast concrete block may be a paving unit, in which case the surface level difference may be greater than 6 mm, such as between 6 mm and 12 mm. In another example of implementation, the dry-cast concrete block may be a wall construction unit, in which case the surface level difference may be greater than 15 mm, such as between 15 mm and 25 mm. Each of a plurality of points of the cast texture may define a respective texture angle between 75 and 90. The cast texture may comprise at least one valley each having a respective depth greater than 4 mm. A process for manufacturing such a concrete block is also provided.