摘要 |
The present invention relates to a method of manufacturing disposable targets used in sports shooting such as clay pigeons, for example, from waste gypsum. The manufacturing method comprises the use of raw material mixture incorporating gypsum grades of different amounts of water of hydration such as CaSO4.2H2O and CaSO4.1/2H2O plus a metal oxide. Furthermore, the method is characterized by comprising the control of the raw material mixture density by the use of suitable fillers, thus controlling the structural strength of the finished product. According to the method, the reaction of the raw material constituents is initiated by adding a suitable amount of aqueous liquid to the mixture and moulding the raw material batch thus obtained under moderate compression, e.g., approx. 0.1-4.2 kN/cm<2>. |