Moisture Content Plays Into Quality

Gypsum is a soft natural mineral that’s mined in quarries and transported to the gypsum board manufacturing facility. Its chemistry is calcium sulfate and it’s sometimes called plaster of paris. Finished gypsum board can be subject to moisture pickup during manufacturing, delivery, handling, and installation. This applies even to moisture-resistant boards and fire-resistant boards. This exposure can come from a variety of sources including improper storage, construction or design defects, water leaks from floods, pipes, rain, or cleanup activities.

Once mined, gypsum is then moved on a conveyor that helps to break the large chunks into smaller pieces for transport to a long rotary drum dryer where 5-10% of the water in the gypsum is removed. It’s necessary to know the moisture content of the incoming rock to properly control the gas-fired rotary dryer’s temperature. After being further processed, the gypsum board enters one of the final stages of its manufacturing process where it enters a forming station to be cut to the proper length and fed into a long drying kiln that offers several zones of temperature. As it moves through this stage of the process, it is once again critical that the moisture levels be measured accurately and efficiently throughout. Proper moisture levels prevent warp, shrinkage, paper delamination, soft edges, brittleness, and more. 

Gypsum Board

Gypsum board may start out wet, but it’s important for it to end up dry. Gypsum board moisture content will affect the drying time and final outcome of the product. High humidity can impact gypsum board causing it to warp. This causes an issue with wasted materials and higher energy costs due to longer drying times in the drying chamber.