Sand mould for casting turbine wheel

摘要

The mould consists of top and bottom boxes in which the cavities partially forming the cast wheel blade surfaces are produced by sand cores (16) placed into the bottom box (10). A partial mould (13) is produced by a partial pattern of the turbine wheel. This partial mould - besides forming the blade cone (12) for each blade (11) - produces partial blade surfaces (14) and stopping surfaces (15) between adjacent blades for sand cores (17). When rotated until in contact with their respective stopping surfaces, these sand cores complete the mould surfaces for the turbine wheel. The guide elements for the sand cores in the bottom box take the form of keyways and keys. For additional location/fixing, each sand core is provided with an end element which partially overlaps the periphery of the preceding sand core.