A placement method in which a mixed low-cement castable is pumped like concrete to the nozzle, where compressed air and a set accelerator are added so it sticks and stiffens on impact. Compared with dry gunning, shotcrete gives higher density, lower rebound and less dust, close to cast properties. It is used for large linings such as blast furnace stack relines, cement preheater cyclones and big ducts.
Stack reline is all shotcrete, two pumps running round the clock until the top is done.
Also heard as
- wet gunning
- refractory shotcrete
Related terms
Gunning
Spraying refractory through a hose and nozzle with compressed air to build or repair a lining.
Rebound
Material that bounces off the wall during gunning instead of sticking, wasted and often harmful.
Nozzleman
Operator who handles the gunning nozzle and controls water and placement on a gunning or shotcrete crew.
Low-cement castable
Dense castable with 1 to 2.5 percent lime from cement, using micro-fines and dispersants for strength and low porosity.