GUNITE HOSE & COUPLINGS

Gunite hose is used by gunite contractors to deliver gunite materials from the gunite machine to the gunite nozzle. Gunite hose is made of a unique formulation of rubber on the interior and covered with a synthetic rubber exterior. It normally includes a reinforcement fabric layer to add strength to the overall gunite hose. These three layers are all visible at the end of the gunite hose. Different from other concrete and shotcrete material delivery hoses, gunite hoses are designed for the most efficient delivery of the dry sand and cement used in the gunite process. Gunite hose is not made to be used with any water, making it unlike concrete shotcrete hose, which is made for pumping wet concrete. Instead of pumping material, gunite contractors use large air compressors to “blow” or convey the dry sand and cement, ie dry gunite material, through the gunite hose with the skilled operation of the gunite machine. Gunite hose is very versatile and can be connected to almost any gunite machine with the right hose coupling from the manufacturer. These gunite hose couplings are connected to the gunite hose with a set of bolts and can be interchanged as desired. Two couplings are required--one coupling for connecting the gunite hose to the gunite machine and a second coupling for connecting the gunite hose to the gunite nozzle, where the water is added to the dry gunite materials before “shooting” on the gunite construction surface. During operation, gunite hoses are subject to relatively low pressures under 150 psi. This operating pressure is much lower than hose pressures in concrete pumping or shotcrete. This is because dry sand and cement traveling through the hose exert a lower pressure than a heavier, wet concrete confined inside of a concrete hose. Gunite hoses are normally offered by their inside diameter (I.D.). The most common gunite hoses are 2” ID and 1-1/2” ID.