摘要:
A cement board of homogeneous composition from face to face and having a substantially uniform thickness is made continuously by distributing a sole cementitious composition on a moving carrier sheet and smoothing the surface by rotating a cylindrical roller in a direction counter to the movement of the carrier sheet. An upper reinforcing network is submerged under the surface by feeding it under the counter rotating roller.
摘要:
The invention provides a process for producing fabric-reinforced, thin concrete panels suitable as a backer board for construction materials such as ceramic tile, slate or thin brick. A process is described whereby the components of the panel are deposited on a web of release-agent-treated, water-absorbent paper while moving on a conveyor belt to form a continuous strip, the strip is cut into panels and the wet, uncured panels are stacked by means of an air-float stacking unit, then subsequently cured with the paper web between adjacent panels.
摘要:
An apparatus for applying parallel spaced-apart creases on paper to be used as cover sheets in the manufacture of gypsum board, the parallel spaced-apart creases forming the corners of the wallboard and the distance between creases defining the thickness thereof, the apparatus being adjustable to control the depth of the creases applied so that substantially no paper material is removed during the creasing process, and the creases applied are of sufficient depth to permit sharp corners to be readily formed.
摘要:
A method of producing a gypsum plaster board. This method includes a step of preparing a starch paste which is effective to bond the gypsum core member and both paper boards. In this step, first, about 10-30 wt % of starch such as corn starch based on water is added to water and mixed to obtain milk of starch. Next, about 0.1-1.5 wt % of amylolytic enzyme such as .alpha.-amylase based on the starch is added and then heated to the decomposition point of the starch with stirring. After the heating is stopped at the range of DH 0.1-10, about 0.8-1.0 wt % of an enzyme deactivating agent based on the starch is added and mixed with water to prepare a starch paste. After the starch paste being prepared by the aforementioned process, a raw material of the gypsum core member, that is, calcined gypsum, reinforcing agent such as glass fiber, weight reducing agent such as surface active agent and the starch paste are mixed with water to obtain gypsum slurry. Then, the gypsum slurry is poured between porous sheets such as paper boards. Thereafter, the unset gypsum plaster board is molded to a predetermined thickness by a molding roller and is set by hydration at room temperature. The set gypsum plaster board is cut to a predetermined size by a cutting machine, and it is dried at about 50.degree.-200.degree. C. to evaporate excessive moisture in the gypsum plaster board.
摘要:
A method and apparatus for forming shaped articles from glass fiber reinforced gypsum. An aqueous slurry of gypsum hemi-hydrate, water and glass fibers contains between 22 and 45 parts by weight water, 100 parts by weight gypsum hemi-hydrate and 3 to 10 parts by weight glass fiber. The slurry is deposited as a continuous ribbon on a moving, water-impermeable formable sheet which is pre-shaped and thereafter the slurry ribbon is pressed into a desired profile. The formable sheet and slurry ribbon are maintained in the desired profile until the slurry sets. Thereafter the product ribbon is cut transversely into lengths as desired. The formable sheet may be removed before cutting, or may be retained in engagement with the product ribbon during and after cutting to serve as a protective cover for the surface of the article. The process and apparatus are especially adapted to produce liner sheets for building construction panels. The process and apparatus also are applicable to producing continuous ribbons of other dough-like formable compositions such as glass-fiber reinforced cement.
摘要:
A specially prepared fiber reinforcement and improved gypsum wallboard are disclosed. The fiber reinforcement includes a multiplicity of relatively long fibers which are disposed at the interface of the core and cover sheets of the wallboard and are adhesively bonded to the cover sheets and incorporated predominantly into the portion of the core immediately adjacent to the cover sheets.
摘要:
The invention relates to the reinforcement of the edges of cementitious board and especially plasterboard. Reinforcing strips are secured to at least one edge of the lower sheet employed in the manufacture of plasterboard and is incorporated with the sheet in the formed board as an edge reinforcement. The reinforcing strip may have any desired cross-section or profile but preferably has a channel section whereby the corners of the board are protected. It may also be grooved longitudinally to provide a kerfed edge to the board which is useful when securing the boards by means of concealed supports.