Gypsum is a common mineral found in many places around the world. The scientific name for raw gypsum is anhydrous calcium sulphate. Gypsum contains a large amount of water in crystalline form. The process of making gypsum products involves removal of the moisture content from the raw ore and re-introducing the moisture in the fabrication of gypsum wallboard products. Plants for converting gypsum from a raw state to finished products are several acres in size.
Mine the raw gypsum ore using open face mining techniques. Use power shovels to dig it from the ore deposit and load it on trucks for transfer to a specialized gypsum manufacturing plant.
Crush the raw gypsum ore into a fine powder in a rock crusher and ball mill. Place the powdered gypsum in a large rotating kiln at 150 degrees Fahrenheit, to drive the crystalline moisture from the powder, in a process called calcining. Convert the raw gypsum into stucco with the calcining process. Store stucco in large hoppers ready for continuous mixing with liquid additives.
Introduce additives to improve handling -- along with water and a foaming agent -- to the stucco, and mix continuously in a wet mixer to create slurry. Distribute the slurry evenly on a layer of paper, as it moves down a large production belt.
Fold the edges of the bottom layer of paper inward, and adhere the back layer of paper to the moving product with a wet adhesive. Place the forming board on a hardening and forming line. This normally over 750 feet in length.
Cut the formed gypsum boards slightly larger than finished size -- at the end of the hardening and forming line -- with an automatic cross-cutting saw.
Transfer the wet sheets into a multi-stage dryer on a transfer table. Move the wet boards through the drying oven for 40 to 45 minutes. Transfer the dry gypsum board to a finishing line.
Flip two sheets of gypsum board face-to-face on the finishing line. Trim the finished boards to precise sizes of 8 feet, 10 feet or 12 feet lengths, using automatic end trimming saws. Apply paper binding tape to both ends of the finished bundle of two boards. This is to identify the size and type of gypsum board product, the brand and the date the product was made. Store the finished bundles in stacks of 50, in a clean, dry warehouse.
Ned Millis has been published in "Tennis Industry Magazine," "Golf Industry Magazine," "Sales Management Magazine" and other trade publications. He is a graduate of Claremont Men's College.