초록 ▼

An improved process for forming objects such as turbine nozzles (10) with internal geometries without requiring machining of the internal geometry to produce a smooth complex internal surface (16, 18 and 19) is disclosed. The process includes forming a mandrel (30) containing a negative image of the

An improved process for forming objects such as turbine nozzles (10) with internal geometries without requiring machining of the internal geometry to produce a smooth complex internal surface (16, 18 and 19) is disclosed. The process includes forming a mandrel (30) containing a negative image of the internal geometry; coating the mandrel with a material (32) which is not chemically reactive with the material from which the mandrel is formed, capturing the mandrel in a mold or form (34) which is to receive the material from which the object is to be formed, the material (36) from which the object is to be made not being chemically reactive with the coating; filling the mold or form with the material to capture the mandrel and coating in solidified material contained in the form; and removing the form and the mandrel. If the material is a cast metal, the melting point of the material for forming the object should be below the melting point of the coating on the mandrel.

대표청구항 ▼

A process for making a turbine nozzle having a gas flow path with an internal geometry without requiring machining of the internal geometry to produce a smooth internal surface comprising: forming a mandrel containing a negative image of the internal geometry; coating the mandrel with a nonferrous m

A process for making a turbine nozzle having a gas flow path with an internal geometry without requiring machining of the internal geometry to produce a smooth internal surface comprising: forming a mandrel containing a negative image of the internal geometry; coating the mandrel with a nonferrous material which is not chemically reactive with the material from which the mandrel is formed; capturing the mandrel in a mold which is to receive a molten metal from which the turbine nozzle is to be cast, the molten metal from which the turbine nozzle is to be cast not being chemically reactive with the coating and having a melting point below the melting point of the material of the coating; filling the mold with molten casting metal to capture the mandrel and coating in solidified casting material contained in the mold; and removing the mold and the mandrel from the turbine nozzle while retaining the non-ferrous material as the gas flow path of the turbine nozzle.