METHOD AND APPARATUS FOR MANUFACTURING ARTICLES OF HYDRAULIC SUBSTANCES

摘要

A method and apparatus are provided for manufacturing articles made of hydraulic cement. The method includes the steps of preparing a plurality of moulding spaces adapted to be closed in a hermetic manner and having sufficient pressure-proof against the inner pressure therein, which pressure is raised during introduction and heat curing of hydraulic cement; introducing hydraulic cement into the mounding spaces substantially to fill the same by utilizing the pressure difference between the inner side and the outer side of the moulding space; indirectly heat curing the hydraulic cement substantially completely around the same immediately after the introduction of the cement is finished, the temperature thereof being rapidly raised up to more than 60.degree.C, and releasing the cured articles from the moulding spaces. The apparatus includes a vertical stack of a plurality of moulds, each including a side frame and a hollow bed overlying the side frame; sealing means interposed between the side frames and the beds for hermetically sealing the moulds; means for releasably interconnecting the stacked moulds; means for reducing the pressure in the moulds; means for pouring the hydraulic cement into the moulds; means for admitting a heating medium into said hollow beds, for indirectly heat curing said hydraulic substance poured into said moulds. This invention thus enables the manufacture of moulded articles of cement having high mechanical strength in a short time, and yet which can be readily removed from the moulds.