A process for controlling the embedding depth of reinforcing mesh to a cementitious board is disclosed. The process comprises applying a pressure from a plate to a reinforcing mesh on a core mix moving downstream on a conveyor, wherein the plate vibrates at a rate that assists in embedding the reinforcing mesh at a depth within the core mix such that the reinforcing mesh is barely visible.

The present invention relates to processes and apparatuses for producing hydrophobized fiber cement sheets as well as fiber cement sheets obtainable therewith. In particular, the present invention provides processes for manufacturing a hydrophobized fiber cement product, said process at least comprising the steps of: (i) forming at least one fiber cement film on a rotating sieve in contact with a fiber cement slurry in a vat; (ii) transferring said at least one fiber cement film from said sieve to a felt transport belt, (iii) applying a mist of a hydrophobizing agent to said at least one fiber cement film, and (iv) accumulating the fiber cement film on an accumulator roll via the felt transport belt, so as to form a hydrophobized fiber cement product. The present invention further relates to various uses of the fiber cement sheets obtainable by the processes of the invention in the building industry.

A slurry feed apparatus for depositing a slurry upon a moving forming web having a direction of travel, including: a headbox mounted transverse to the direction of travel of the moving web, having a back wall, sidewalls, a concave transverse front wall, an open top, and an open bottom for directing slurry onto the forming web; a moveable dam releasably attached to the back wall, a seal attached to a bottom wall of the dam; and a headbox support system extending from opposed the sidewalls. Also disclosed is a continuous process for depositing a uniform layer of a cementitious slurry containing reinforcing fibers from the headbox onto a traveling web.

A method in which a stream of dry cementitious powder from a dry powder feeder passes through a dry cementitious powder inlet conduit to feed a first feed section of a fiber-slurry mixer. An aqueous medium stream passes through at least one aqueous medium stream conduit to feed a first mixing section the fiber-slurry mixer. A stream of reinforcing fibers passes from a fiber feeder through a reinforcing fibers stream conduit to feed a second mixing section of the fiber-slurry mixer. The stream of dry cementitious powder, aqueous medium stream, and stream of reinforcing fibers combine in the fiber-slurry mixer to make a stream of fiber-cement mixture which discharges through a discharge conduit at a downstream end of the mixer.

The present invention relates to processes and apparatuses for producing fiber cement sheets as well as fiber cement sheets obtainable therewith. The processes according to the present invention at least comprise the steps of: (a) providing a cementitious slurry comprising fibers, (b) continuously discharging the slurry on an endless water-permeable transport belt, and (c) removing excess of water from the slurry through the water-permeable transport belt to form a fiber cement sheet with a predetermined thickness. By using a water-permeable transport belt for removing the excess of water from the fiber cement sheet, both the thickness and the density of the sheet can be accurately tuned, without resulting in a spring-back of the thickness of the sheet at the end of the production process. The present invention further relates to various uses of the fiber cement sheets obtainable by the processes of the invention in the building industry.

Continuous method including: mixing water and cementitous powder to form slurry; mixing the slurry and reinforcement fibers in a single pass horizontal continuous mixer to form fiber-slurry mixture, the mixer including an elongated mixing chamber having a reinforcement fiber inlet port, and upstream of the fiber inlet port is an inlet port to introduce water and cementitous powder together as one stream or at least two inlet ports to introduce water and dry cementitous powder separately as separate streams into the chamber, a rotating horizontal shaft/s within the chamber, part of the chamber for mixing the fibers and slurry and moving the fiber-slurry mixture to a mixture outlet; discharging the fiber-slurry mixture from the mixer outlet; forming and setting the fiber-slurry mixture on a moving surface; cutting the set mixture into fiber reinforced concrete panels and removing the panels from the moving surface.

A process for the formation of highly durable cementitious board using lightweight aggregate is disclosed. The process comprises pouring a core mix onto a conveyor, wherein the core mix is comprised of one or more lightweight aggregate filler in the amount of 0.5 to 5 weight percent of the core mix, one or more binders in the amount of 35 to 75 weight percent of the core mix, rheological admixture in the amount of about 0.5 to 5 weight percent of the core mix, surfactant in the amount of 0 to 0.1 weight percent of the core mix, one or more normal weight aggregate filler in the amount of 5 to 50 weight percent of the core mix, and water in the amount of 5 to 20 weight percent of the core mix. The process further comprises passing the core mix under a screed roller to flatten the core mix to produce an extruding board with a desired thickness.