Shotcrete is an alternative application method to dry gunning. It is referred sometimes as wet gunning.
Shotcrete requires specific deflocculated castable with specific grain size distribution and adequate additives (e.g. Peramin® AL 200 and Peramin® AL 300 for high fluidity). The formulation is prepared in a paddle mixer until the mix gets its right consistency. Contrary to dry gunning, water is added before pumping. The refractory castable (refractory concrete) is transported by a double piston pump and an accelerating agent is added at the nozzle. The mix sets and hardens on the service location.
In comparison to dry gunning, shotcrete does not generate any dust, has low rebound from the wall and can get output up to 10 t / h.
Technical article on www.secar.net is available on shotcrete:
- 2002 - The optimisation of CAC based castable systems for wet shotcreting applications in steel ladles