Mold assembly and method of making the same

A method of making a mold assembly for use in casting a one-piece turbine engine component having a circular inner wall and a circular outer wall interconnected by a plurality of radially extending struts, said method comprising the steps of providing a plurality of disposable inner wall section patterns, a plurality of disposable outer wall section patterns and a plurality of disposable strut section patterns, applying a coating of a ceramic mold material to each of the patterns, forming separate inner wall, outer wall and strut mold sections made of ceramic mold material by disposing of the patterns after performing said step of applying a coating of ceramic mold material to each of the patterns, said step of forming separate inner wall, outer wall and strut mold sections includes the steps of forming a first plurality of inner wall mold sections each of which has a surface with a configuration corresponding to the configuration of a portion of a circular radially inner surface area of the inner wall of the turbine engine component, forming a second plurality of inner wall mold sections each of which has a surface with a configuration corresponding to the configuration of a portion of a circular radially outer surface area of the inner wall of the turbine engine component, forming a first plurality of outer wall mold sections each of which has a surface with a configuration corresponding to the configuration of a portion of a circular radially inner surface area of the outer wall of the turbine engine component, forming a second plurality of outer wall mold sections each of which has a surface with a configuration corresponding to the configuration of a portion of a circular radially outer surface area of the outer wall of the turbine engine component, forming a first plurality of strut mold sections each of which has a configuration corresponding to the configuration of at least a portion of one side of a strut, and forming a second plurality of strut mold sections each of which has a configuration corresponding to the configuration of at least a portion of a side of a strut opposite from said one side, said method further including the steps of interconnecting the first plurality of inner wall mold sections in a first circular array of inner wall mold sections, interconnecting the second plurality of inner wall mold sections in a second circular array of inner wall mold sections which cooperates with the first circular array of inner wall mold sections to at least partially define a mold cavity having a configuration corresponding to the configuration of the inner wall of the turbine engine component, interconnecting the first plurality of outer wall mold sections in a first circular array of outer wall mold sections, interconnecting the second plurality of outer wall mold sections in a second circular array of outer wall mold sections which cooperates with the first circular array of outer wall mold sections to at least partially define a mold cavity having a configuration corresponding to the configuration of the outer wall of the turbine engine component, interconnecting each of the first plurality of strut mold sections with one of the second plurality of strut mold sections to at least partially define a plurality of strut section mold cavities having a configuration corresponding to the configurations of the struts of the turbine engine component, and interconnecting the strut mold sections with the first circular array of outer wall mold sections and with the second circular array of inner wall mold sections.

A mold assembly for use in forming a one-piece turbine engine component having a circular inner wall and a circular outer wall interconnected by a plurality of radially extending struts, said mold assembly comprising a first plurality of inner wall mold sections disposed in a first circular array, each of said first plurality of inner wall mold sections having a major side surface with a configuration corresponding to the configuration of at least a portion of a radially inner side surface of the inner wall of the turbine engine component, a second plurality of inner wall mold sections disposed in a second circular array circumscribing at least a portion of said first circular array of inner wall mold sections, each of said second plurality of inner wall mold sections having a major side surface with a configuration corresponding to the configuration of at least a portion of a radially outer side surface of the inner wall of the turbine engine component, means for interconnecting said first and second pluralities of inner wall mold sections to at least partially define a first annular mold cavity having a configuration corresponding to the configuration of the inner wall of the turbine engine component, a first plurality of outer wall mold sections disposed in a first circular array of outer wall mold sections circumscribing said first and second circular arrays of inner wall mold sections, each of said first plurality of outer wall mold sections having a major side surface with a configuration corresponding to the configuration of at least a portion of a radially inner side surface of the outer wall of the turbine engine component, a second plurality of outer wall mold sections disposed in a second circular array of outer wall mold sections and circumscribing at least a portion of said first circular array of outer wall mold sections, each of said second plurality of outer wall mold sections having a major side surface with a configuration corresponding to the configuration of at least a portion of a radially outer side surface of the outer wall of the turbine engine component, means for interconnecting said first and second pluralities of outer wall mold sections to at least partially define a second annular mold cavity having a configuration corresponding to the configuration of the outer wall of the turbine engine component, a first plurality of strut mold sections each of which has a configuration corresponding to the configuration of at least a portion of a first side of a strut of the turbine engine component, a second plurality of strut mold sections each of which has a configuration corresponding to the configuration of at least a portion of a second side of a strut of the turbine engine component, means for interconnecting said first and second pluralities of strut mold sections to at least partially define a plurality of strut mold cavities having a configuration corresponding to the configuration of the struts of the turbine engine component, means for connecting said strut mold sections with said second circular array of inner wall mold sections with said first annular mold cavity connected in fluid communication with each of said strut mold cavities, and means for connecting said strut mold sections with said first circular array of outer wall mold sections with said second annular mold cavity connected in fluid communication with each of said strut mold cavities.

A method of making a mold assembly for use in forming a cast product having opposite side surfaces, said method comprising the steps of providing a disposable pattern having a body with an outwardly extending flange, the pattern body having opposite side surfaces which have configurations corresponding to the configurations of the side surfaces of the cast product and are spaced further apart than the side surfaces of the cast product, said method further including the steps of coating at least the body and flange of the pattern with a liquid ceramic mold material, wiping away the wet coating overlying a portion of the flange, drying the wet coating after performing said wiping step, repeating the coating, wiping, and drying steps until a covering of ceramic mold material of a desired thickness has been built up on at least part of the pattern, providing a pair of separate mold sections which have mold surfaces with configurations corresponding to the configurations of the side surfaces of the cast product, said step of providing a pair of separate mold sections including the step of destroying the disposable pattern, and thereafter locating the mold surfaces on the separate mold sections in the same spatial relationship as the opposite side surfaces on the cast product by placing in abutting engagement surfaces on the mold sections which were previously disposed on opposite sides of the pattern flange.

A method of making a mold assembly for use in forming a cast product having opposite side surfaces, said method comprising the steps of providing a disposable pattern having a body with an outwardly extending flange, the pattern body having opposite side surfaces which have configurations corresponding to the configurations of the side surfaces of the cast product and are spaced further apart than the side surfaces of the cast product, said method further including the steps of coating at least the body and flange of the pattern with a liquid ceramic mold material, drying the coating on the pattern, repeating the coating and drying steps until a covering of ceramic mold material of a desired thickness has been built up on at least part of the pattern, said steps of repetitively coating and drying includes the steps of applying an initial covering of ceramic mold material over the body and flange of the pattern and drying the initial covering, said step of coating the pattern further including the step of applying a wet coating of ceramic mold material over the initial covering, said method further including the step of removing a portion of the wet coating overlying the initial covering on the flange of the pattern prior to drying of the wet coating overlying the initial covering, providing a pair of separate mold sections which have mold surfaces with configurations corresponding to the configurations of the side surfaces of the cast product, said step of providing a pair of separate mold sections including the step of destroying the disposable pattern, and thereafter locating the mold surfaces on the separate mold sections in the same spatial relationship as the opposite side surfaces on the cast product by placing in abutting engagement surfaces on the mold sections which were previously disposed on opposite sides of the pattern flange.

A method of making a ceramic mold assembly for use in forming a cast product, said method comprising the steps of providing a pattern having a body section connected with a gating section, the pattern body section having a first major side surface with a configuration corresponding to a first surface area of the cast product, a second major side surface with a configuration corresponding to a second surface area of the cast product and minor side surfaces interconnecting the major side surfaces of the pattern body section, the pattern gating section being connected with the first major side surface of the pattern body section and having a configuration corresponding to the configuration of a portion of the mold assembly through which molten metal flows to a mold cavity during a casting operation, said method further including the steps of applying a wet coating of liquid ceramic mold material over the pattern body section and at least a portion of the gating section, removing at least a major portion of the wet coating of ceramic mold material overlying a plurality of minor side surfaces of the pattern body section to at least partially separate the portion of the wet coating of ceramic mold material overlying the first major side surface of the pattern body section from the portion of the wet coating of ceramic mold material overlying the second major side surface of the pattern body section, at least partially drying the wet coating of ceramic mold material overlying the pattern body section and gating section after performing said steps of removing the wet coating of ceramic mold material overlying the minor side surfaces of the pattern body section, separating the pattern body section and gating section from the dried coating of ceramic mold material to provide a first ceramic mold section connected with a ceramic mold gating section and a second ceramic mold section which is separate from the first mold section and the mold gating section, and interconnecting the first and second ceramic mold sections to at least partially define a mold cavity connected in fluid communication with the mold gating section.

A method of making a ceramic mold assembly for use in forming a cast product, said method comprising the steps of providing a pattern having a main pattern section and first and second flange pattern sections connected with opposite end portions of the main pattern section and extending transversely to the main pattern section, the main pattern section having a first major side surface with a configuration corresponding to a first surface area of the cast product and a second major side surface with a configuration corresponding to a second surface area of the cast product, the first and second flange pattern sections each having a first major side surface connected with an end portion of the main pattern section and projecting outwardly of the first and second major side surfaces of the main pattern section, said method further including the steps of repetitively applying wet coatings of ceramic mold material over the pattern, at least partially drying each of the wet coatings of ceramic mold material in turn, separating at least some of the wet coatings of ceramic mold material into a plurality of segments before drying these coatings, said step of separating a wet coating of ceramic mold material into a plurality of segments including the steps of forming the wet coating of ceramic mold material into a first segment overlying the first major side surface of the main pattern section and portions of the first and second flange pattern sections and a second segment overlying the second major side surface of the main pattern section and portions of the first and second flange pattern sections, said steps of forming the wet coating of ceramic mold material into first and second segments including the steps of removing at least a major portion of the wet coating of ceramic mold material overlying minor side surfaces of the main pattern section and surface areas of the first and second flange pattern sections, separating the first and second segments of the coating of ceramic mold material overlying the major side surfaces of the main pattern section and first and second flange pattern sections from the pattern by destroying the pattern after performing said steps of applying and drying coatings of ceramic mold material, and thereafter interconnecting the first and second segments of ceramic mold material to at least partially form the mold assembly, said step of interconnecting the first and second segments of ceramic mold material including the step of forming joints in association with the portions of the first and second segments of ceramic mold material which previously overlaid the first and second flange pattern sections.

A method of making a mold assembly for use in casting a circular wall, said method comprising the steps of providing a plurality of disposable arcuate wall patterns, applying a wet coating of liquid ceramic mold material to each of the arcuate wall patterns, at least partially drying the wet coating of liquid ceramic mold material on each of the arcuate wall patterns, forming a plurality of separate arcuate mold sections made of ceramic mold material by disposing of the patterns after performing said steps of applying and drying a coating of ceramic mold material, said step of forming separate arcuate mold sections including the steps of forming a first plurality of arcuate mold sections each of which has a surface with a configuration corresponding to the configuration of a portion of a circular radially inner surface area of the circular wall to be cast and forming a second plurality of arcuate mold sections each of which has a surface with a configuration corresponding to the configuration of a portion of a circular radially outer surface area of the circular wall to be cast, said method further including the steps of interconnecting the first plurality of arcuate mold sections in a first circular array of mold sections, and interconnecting the second plurality of arcuate mold sections in a second circular array of mold sections which is circumscribed by the first circular array of mold sections and cooperates with the first circular array of mold sections to at least partially define a circular mold cavity having a configuration corresponding to the configuration of the wall to be cast.