Exportadora del Sal S.A. (ESSA) operates huge sea water salt evaporation ponds not far from the city of Guerrero Negro in Western Mexico. The salt level “grows” by about 20 cm over the course of one year. The resulting salt crust needs to be harvested with great precision (Fig. 1) to allow for a maximum salt yield, create an even and clean surface and avoid damage to the newly forming salt crust.
The Wirtgen Surface Miner 2200 SM, which has been designed with a maximum cutting depth of 25 cm, a cutting width of 3.8 m and an engine output of 708 kW/963 PS, is perfectly tailored to meet this challenge (Fig. 2). The cutting drum is mounted close to the machine’s center of gravity to guarantee maximum cutting performance. It produces even, stable surfaces that are ideally suited to the use of trucks. The four track units can be adjusted in height separately via hydraulic cylinders to allow accurate setting of both cutting depth and cross slope.
The machine is utilized to optimum capacity when operating at an average cutting depth of 20 cm and working speed of 15-20 m/min. Since 2012, the 2200 SM has been setting new standards in ESSA’s salt mine. The fines content of the mining material precisely meets customer specifications – and the machine’s performance is quite impressive, too: the 2200 SM harvests an average 895 t/h of salt at diesel consumption rates of only 0.12 l/t respectively.