A method for making a wax model for the manufacture of a part, the part including at least one cavity, the method including: arranging at least two core elements made of a ceramic material into a wax mold, the core elements having at least partially a shape complementary to the cavity of the part to be manufactured, and injecting wax into the wax mold, around the core elements, so as to form the wax model, the two core elements being assembled prior to the injection of wax by at least one staple, the staple including a central portion from which two branches extend, each branch being fitted into an orifice formed in one of the core elements.

A method for making a wax model for the manufacture of a part, the part including at least one cavity, the method including: arranging at least two core elements made of a ceramic material into a wax mold, the core elements having at least partially a shape complementary to the cavity of the part to be manufactured, and injecting wax into the wax mold, around the core elements, so as to form the wax model, the two core elements being assembled prior to the injection of wax by at least one staple, the staple including a central portion from which two branches extend, each branch being fitted into an orifice formed in one of the core elements.

A differential carrier case with an inserted pipe for high pressure casting may include a mold core into which a first end of a pipe is inserted, a mold core pin fixed to the mold core to fix the mold core and the first end of the pipe, a drive core pin inserted into a second end of the pipe, and a thick portion surrounding an outer portion of the pipe.

A differential carrier case with an inserted pipe for high pressure casting may include a mold core into which a first end of a pipe is inserted, a mold core pin fixed to the mold core to fix the mold core and the first end of the pipe, a drive core pin inserted into a second end of the pipe, and a thick portion surrounding an outer portion of the pipe.

The buoyancy transfer jig includes: a rod-shaped rod portion which is disposed extending from an outside of a pattern to an inside of a hollow portion by way of an opening portion which is formed in a foamed mold and makes the outside of the pattern and the hollow portion connected with each other, and is disposed in self hardening sand filled in the hollow portion and the opening portion; and a plate-shaped blade portion which is formed continuously with the rod portion and is disposed in the casting sand.

The buoyancy transfer jig includes: a rod-shaped rod portion which is disposed extending from an outside of a pattern to an inside of a hollow portion by way of an opening portion which is formed in a foamed mold and makes the outside of the pattern and the hollow portion connected with each other, and is disposed in self hardening sand filled in the hollow portion and the opening portion; and a plate-shaped blade portion which is formed continuously with the rod portion and is disposed in the casting sand.

An opening is provided in a foam pattern, and a coating agent is applied to the opening. The coating agent applied to the opening is taken as a beam having a sectional secondary moment I (mm.sup.4), a vertical plate thickness h (mm), and a length L (mm). It is assumed that a volume of a cavity part in the foam pattern is V (mm.sup.3), a bulk density of the casting sand filling the cavity part is s (kg/mm.sup.3), a gravitational acceleration is g (mm/sec.sup.2), a density of the melt is m (kg/mm.sup.3), an angle of the opening with respect to a vertical direction is , and a transverse strength of the coating agent at the highest temperature during pouring of the melt is b (MPa). A sectional shape of the opening, the angle of the opening, and the transverse strength b of the coating agent are selected to satisfy the expression:
bI>V(ms)g{(hL/2)sin cos }.

A method of forming an airfoil (12), including: abutting end faces (72) of cantilevered film hole protrusions (64) extending from a ceramic core (50) against an inner surface (80) of a wax die (68) to hold the ceramic core in a fixed positional relationship with the wax die; casting an airfoil including a superalloy around the ceramic core; and machining film cooling holes (34) in the airfoil after the casting step to form an pattern of film cooling holes comprising the film cooling holes formed by the machining step and the cast film cooling holes (102) formed by the film hole protrusions during the casting step.

A method of forming an airfoil (12), including: abutting end faces (72) of cantilevered film hole protrusions (64) extending from a ceramic core (50) against an inner surface (80) of a wax die (68) to hold the ceramic core in a fixed positional relationship with the wax die; casting an airfoil including a superalloy around the ceramic core; and machining film cooling holes (34) in the airfoil after the casting step to form an pattern of film cooling holes comprising the film cooling holes formed by the machining step and the cast film cooling holes (102) formed by the film hole protrusions during the casting step.

An assembly for manufacturing a wax moulding of a turbine engine blade has a wax injection mould in which a core is able to be mounted in a predetermined moulding position, the core including a main element and at least a first secondary element each including at least one functional part and a non-functional part, wherein the non-functional part of the first secondary element includes a rod portion extending in a longitudinal direction of the blade and housed in a first slot of the non-functional part of the main member, the mould including a first internal boss clamping said rod portion at the bottom of the first slot.