Patent ID: 7854397
Filing Date: 2010-12-21
Classification: B05B,E04F,E04G,F27D

Abstract:
1. A refractory concrete gunning apparatus for the gunning of a wetted dry mix or wet mix refractory concrete gunning material comprising: a nozzle having an inner passage wherein the inner passage has an inlet end, into which a wetted dry mix or wet mix refractory concrete gunning material is to be introduced, the inlet end being dimensioned and configured for the introduction of the wetted dry mix or wet mix and an outlet end from which the wetted dry mix or wet mix refractory concrete gunning material is to be sprayed, wherein the inner passage is defined by an inner tubular member and has a substantially constant diameter; and an outer passage defined by an outer tubular member disposed around the inner tubular member and in fluid communication therewith, the outer tubular member having an inlet end for introducing a gas to be passed through the outer passage and an outlet end from which the gas exits and impinges on the wetted dry mix or wet mix refractory concrete gunning material exiting the outlet end of the inner passage, the inner tubular member and the outer tubular member each having an inner surface and an outer surface, wherein the inner tubular member comprises a plurality of through slots circumferentially arranged near the inlet end and connecting the outer passage with the inner passage allowing the outer passage and the inner passage to be in fluid communication to deliver a portion of the gas from outer passage to the inner passage for accelerating the wetted dry mix or wet mix refractory concrete gunning material through the inner passage, and further wherein the outlet end of the inner tubular member extends beyond the outlet end of the outer tubular member and the outer surface of the outlet end of the inner tubular member is chamfered and the inner surface of the outlet end of the outer tubular member is chamfered at a same angle.