Gunning mix (refractory gunning mix) is composed of refractory materials with a certain particle gradation, chemical binders and admixtures. It is an unshaped refractory material used when repairing the lining of thermal equipment by spray construction. It is a main type of spray material.

According to the gunning material state and spraying method, it can be divided into three types:

(1) Wet gunning, generally only thin-layer repairing.

(2) Dry gunning (also called semi-dry gunning), which can be used for thicker layer gunning, and is the most widely used.

(3) Flame gunning can obtain a densely structured gunning layer with high bonding strength and strong erosion resistance and erosion resistance.

According to the state of receiving sprayed materials on the spray working surface, it can be divided into:

(1) The molten material injection method is divided into 3 types: flame injection method, plasma injection method, and slag splashing method.

(2) The cold material injection method is divided into 5 types: mud injection method, dry injection method, semi-wet injection method (or wet injection method), mixed injection method, and wet injection method.