Refractory metal core wall thickness control
In accordance with the present invention, a casting system is provided which broadly comprises a core and a wax die spaced from said core, a refractory metal core having a first end seated within a slot in the core and a second end contacting the wax die for positioning the core relative to the wax die, and the refractory metal core having at least one of a mechanism for providing spring loading when closed in the wax die and a mechanism for mechanically locking the wax die to the core.
1 . A casting system comprising:
a first core and a wax die spaced from said first core;
a refractory metal core having a first end seated within a slot in said first core and a second end contacting said wax die for positioning said first core relative to said wax die; and
said refractory metal core having at least one of a means for providing spring loading when closed in said wax die and a means for mechanically locking the wax die to the first core.
2 . The casting system according to claim 1 , wherein said refractory metal core has said spring loading means and said spring loading means comprises at least one integrally formed spring tab.
3 . The casting system according to claim 2 , wherein said spring loading means comprises a plurality of spaced apart spring tabs.
4 . The casting system according to claim 2 , wherein each said tab has a tapered end.
5 . The casting system according to claim 2 , wherein each said tab has a non-tapered end.
6 . The casting system according to claim 1 , wherein the refractory metal core is formed from a material selected from the group consisting of molybdenum, tantalum, niobium, tungsten, alloys thereof, and intermetallic compounds thereof.
7 . The casting system according to claim 1 , wherein said refractory metal core has said mechanical locking means and said wax die is provided with a slot for receiving said mechanical locking means of said refractory metal core.
8 . The casting system according to claim 7 , wherein said mechanical locking means comprises said second end of said refractory metal core being angled to fit within said slot.
9 . The casting system according to claim 8 , wherein said slot in said wax die has a wall perpendicular to a surface of said wax die and said second end of said refractory metal core abuts said wall.
10 . The casting system according to claim 7 , wherein said mechanical locking means comprises at least one hole in said second end of said refractory metal core.
11 . A refractory metal core for maintaining a core in a desired position with respect to a wax die and avoiding core shift during casting comprising:
a core element formed from a refractory metal material,
said core element having at least one integrally formed spring tab to provide spring loading when closed in said wax die.
12 . A refractory metal core according to claim 11 , wherein said core has a plurality of spaced apart spring tabs.
13 . A refractory metal core according to claim 11 , wherein said core element is formed from a material selected from the group consisting of molybdenum, tantalum, niobium, tungsten, alloys thereof, and intermetallic compounds thereof.
14 . A refractory metal core for maintaining a core in a desired position with respect to a wax die and avoiding core shift during cast comprising:
a core element formed from a refractory metal material,
said core element having a first end, a central portion, and a second end positioned at an angle to said central portion for engaging a slot in said wax die.
15 . A refractory metal core according to claim 14 , wherein the angle between the second end and the central portion is such that said second abuts a wall of said slot.
16 . A refractory metal core according to claim 14 , wherein said second end includes means for mechanically locking the refractory metal core to a shell.
17 . A refractory metal core according to claim 16 , wherein said mechanical locking means comprises at least one tab having at least one hole.
18 . A refractory metal core according to claim 14 , wherein said core element is formed from a material selected from the group consisting of molybdenum, tantalum, niobium, tungsten, alloys thereof, and intermetallic compounds thereof.