US20140290891A1

US20140290891A1 - Chaplet, cast molding system, and method

Info

Publication number: US20140290891A1
Application number: US13/852,384
Authority: US
Inventors: Russell Wilburn; Carlos TREVINO
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 2013-03-28
Filing date: 2013-03-28
Publication date: 2014-10-02
Also published as: WO2014160685A1

Abstract

A chaplet includes a first portion configured to engage one of a core and a mold, a second portion configured to engage the other of the core and the mold, and an elongated rod extending between the first portion and the second portion. The rod has a plurality of breakaway sites for allowing the length thereof to be selectively reduced in predetermined increments.

Description

BACKGROUND

1. Technical Field
Embodiments of the subject matter disclosed herein generally relate to cast molding, and more particularly, to a chaplet for supporting a core within a casting mold.
2. Discussion of the Background
The oil and gas industry continues to locate new sources of natural resources while developing new methods and systems for increasing the output of known sources. As a result, the demand for compressors, gas turbines, electrical motors, and other equipment used in the extraction, processing, and delivery of these resources is on the rise.
One process used in the manufacture of components for such equipment is cast molding. Cast molding typically includes pouring a liquid material into a mold and allowing the material to cool and set. The casting may then be ejected or broken out of the mold to complete the cast molding process. The solidified component is often referred to as a casting.
Cast molding offers manufacturing solutions for metal components having a complex shape which may be difficult or uneconomical to make by other methods. For example, cast molding allows for the insertion of mold cores which allow special features such as voids, cavities, tunnels, etc., to be readily incorporated to the component during the casting process.
Oftentimes, the performance of a core may be controlled, safeguarded or otherwise enhanced by means which serve to position the core relative to the mold. For example, if molten metal is poured quickly into the mold, the core, in the absence of such means, may be displaced by the force of the flowing molten metal, thereby compromising the dimensional accuracy of the special feature represented by the core. If the core is large, additional support may be necessary to maintain the position of the core within the mold.
A chaplet may be used for these and other purposes. Specifically, one or more chaplets may be inserted between a core or cores and the surface of the mold prior to the molten metal being poured. For example, a chaplet may be used to support a core from the bottom of the mold, or to anchor the core from the top and/or side of the mold.
A large number of chaplets may be used in order to mold a single component. Thus, manufacturers may store a variety of chaplets of different configurations in order to ensure that sufficient chaplets are on hand and of the right size to provide a desired function.
Despite these efforts, available chaplets are oftentimes inadequate. For example, one chaplet may be too small while the next available sized chaplet is too large. To address this issue, adjustable chaplets have been proposed. For example, Arthur et al. (GB204,924) disclose a chaplet including a stem having two spacing pieces, both of which are adjustably mounted thereon so as to be movable along the longitudinal axis thereof. However, in Arthur et al., like other adjustable chaplets, moving one or both spacing pieces towards each other may result in the protrusion of the stem outside the distance spanned by the spacing pieces. This is undesirable as the protruding portion of the stem may interfere with, damage or otherwise compromise the mold, the core, or both. Accordingly, what is needed is a versatile, cost-effective chaplet which may be adjustable and which prevents the mold surface, the core, or both from being damaged or otherwise compromised by a protruding portion of the chaplet.

SUMMARY

According to an exemplary embodiment, a chaplet includes a first portion configured to engage one of a core and a mold, a second portion configured to engage the other of the core and the mold, and an elongated rod extending between the first portion and the second portion, the rod having a plurality of breakaway sites for allowing the length thereof to be selectively reduced in predetermined increments.
According to another exemplary embodiment, a system for casting a component of a machine includes a mold having a surface that mirrors an external surface of the component, a core to be positioned in the mold and at least one chaplet to be placed between the mold and the core, the chaplet including a first portion configured to engage one of the core and the mold, a second portion configured to engage the other of the core and the mold, and an elongated rod extending between the first portion and the second portion, the rod having a plurality of breakaway sites distributed along the longitudinal axis thereof for allowing the length of the rod to be selectively reduced in predetermined increments.
According to another exemplary embodiment, a method of positioning a core in a casting mold with a chaplet having a first portion, a second portion, and a rod extending between the first portion and the second portion can include the steps of measuring a distance between a surface of the casting mold and a surface of the core, reducing the length of the rod according to the measurement by cleaving the rod along one of a plurality of grooves in the rod, inserting the chaplet between the surface of the casting mold and the surface of the core such that the first portion engages one of the surface of the casting mold and the surface of the core and the second portion engages the other of the surface of the casting mold and the surface of the core.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate one or more embodiments and, together with the description, explain these embodiments. In the drawings:

FIG. 1 is a perspective view of a chaplet according to an exemplary embodiment.

FIG. 2 is a side view of the chaplet shown in FIG. 1.

FIG. 3 is a close up view of the circled portion of the chaplet shown in FIG. 2.

FIG. 4 is a cross-sectional view of a casting mold system according to another exemplary embodiment.

FIG. 5 shows a method according to another exemplary embodiment.

DETAILED DESCRIPTION

The following description of the exemplary embodiments refers to the accompanying drawings. The same reference numbers in different drawings identify the same or similar elements. The following detailed description does not limit the invention. Instead, the scope of the invention is defined by the appended claims. The following embodiments are discussed, for simplicity, with regard to the terminology and structure of mold casting systems. However, the embodiments to be discussed next are not limited to these exemplary systems, but may be applied to other systems.
Reference throughout the specification to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of the subject matter disclosed. Thus, the appearance of the phrases “in one embodiment” or “in an embodiment” in various places throughout the specification is not necessarily referring to the same embodiment. Further, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.
An exemplary embodiment of a chaplet according to the present invention is shown in FIGS. 1 to 3. Chaplet 14 includes a threaded rod 22 extending between a first portion 16 and a second portion 18. First portion 16 may be connected to a first end of the rod 22 and a second portion 18 may be threadedly connected to a second end of the threaded rod 22.
In the embodiment shown in FIGS. 1-3, the second portion 18 may include an integral nut 28 formed by the deformation of the plate material of second portion 18 or a traditional nut that is attached to the second portion 18 by known means. Specifically, tabs 25 and 27 (FIG. 2) may be formed, for example, by stamping the plate material and deflecting the tabs 25 and 27 away from the plane defined by the plate to form the integral nut 28. This feature may provide a simple, strong, relatively low cost solution for providing adjustability to chaplet 14. Specifically, integral nut 28 may allow second portion to be rotated relative to threaded rod 22 to adjust the distance between first portion 16 and second portion 18. One skilled in the art will appreciate that in alternative embodiments (not shown), both the first portion 16 and the second portion 18 may be threadedly connected to rod 22.
Also, in addition to the above described threaded arrangement for providing adjustability to the distance between first portion 16 and second portion 18 on rod 22, other arrangements are possible for allowing the first portion 16 and/or the second portion 18 to be readily indexed and secured to rod 22 to provide a desired distance therebetween. For example, the second portion 18 may be provided with a hole sized slightly larger than the outer diameter of rod 22 to allow the second portion 18 to be slid along rod 22 until the desired distance is achieved, between first and second portions 16 and 18. The second portion 18 may then be fixed to rod 22, for example, by a chemical connection, such as welding or an adhesive, or by a mechanical connection, for example, by deforming second portion 18 into a frictional engagement with rod 22, or, as another example, by driving a wedge in the space between the hole in second portion 18 and the rod 22.
As further shown in FIGS. 1 to 3, rod 22 includes a plurality of breakaway sites 24 distributed along the longitudinal axis 36 thereof. Breakaway sites 24 allow the length of rod 22 to be selectively reduced in predetermined increments 26 to accommodate a distance between the first portion 16 and the second portion 18. Specifically, breakaway sites 24 allow a user to remove a portion of rod 22 which may protrude beyond an actual or desired distance between the first portion 16 and the second portion 18.
In the embodiment of FIGS. 1 to 3, each breakaway site 24 includes a groove 32 extending through rod 22. Each groove may be provided with a uniform groove width 29, which may be, for example, approximately equal to the width of a thread of the threaded rod 22, as shown in FIG. 3.
Each groove 32 may include a groove floor 34. In the embodiment of FIGS. 1 to 3, each groove floor 34 may define a straight line coincident with a diameter of the rod 22. Grooves 32 may be configured such that adjacent groove floors 34 are non-parallel. For example, and as shown in FIG. 3, adjacent groove floors 34 may be substantially perpendicular.
Each groove 32 may be formed according to a repeating pattern. For example, successive groove floors may be rotationally offset, such that for any groove floor 34 facing a first direction, the nearest parallel groove floor 34 will face a second direction opposite to the first direction. For example, and as shown in FIG. 3, each successive groove floor 34 may be rotationally offset by ninety degrees, i.e., one quarter rotation of rod 22. As further shown in FIGS. 2 and 3, each groove 32 may be further configured to define a plane normal to the longitudinal axis 36 of rod 22.
In use, a length of rod 22 may be identified by the user for removal. Grooves 32 may provide a convenient measuring device for this purpose. Specifically, in the embodiment of FIGS. 1 to 3, grooves 32 are provided in evenly spaced increments 26. If the length of rod 22 which is to be removed is known, a user may simply count the increments 26 to select the groove 32 which will form the new end of the reduced length of rod 22.
In the embodiment of FIGS. 1 to 3, rod 22 may be configured such that the identified length of rod 22 may be removed without tools. For example, rod 22 may be configured such that the user may reduce the length of the rod by bending the rod until the rod 22 cleaves along the plane of the selected groove 32.
For example, a user may orient rod 22 such that the groove floor 34 of the selected groove 32 faces a first direction, for example, upwardly. The user may then grasp the rod on one side of the selected groove 32 with one hand and grasp the rod 22 on the other side of the selected groove 32 with the other hand. The user may then bend the rod 22 such that the ends thereof are forced in a second opposite direction, i.e., downwardly. This may provide the user with the least resistance to bending and cleaving of the rod at the selected groove 32. Rod 22 may be configured such that a user of average strength will be unable to cause the rod 22 to cleave at the selected groove 32 unless grasped and bent in this manner.
Further, cleaving rod 22 at the selected groove 32 may be facilitated by the perpendicular and rotational offset orientation of the successive grooves 32. Specifically, since the selected groove 32 has a groove floor 34 facing a different direction than the surrounding grooves 32, the flexural strength of rod 22 at the surrounding grooves 32 may be greater than the flexural strength of rod 22 at the selected groove 32. As a result, the chance of rod 22 cleaving at a non-selected groove 32 may be reduced. This feature may allow the user to move his or her hands outwardly from the selected groove 34 to gain a greater bending moment, i.e., better leverage, on rod 22.
In the embodiment of FIGS. 1 to 3, each groove 32 is provided with a substantially square profile at groove floor 34. In other embodiments (not shown), groove floors 34 may be provided with other profiles. For example, each groove floor 34 may be provided with, for example, a V-shaped profile which may provide a smaller initial resistance to cleaving of rod 22 about the selected groove 32 and/or enhance the likelihood that cleaving will occur precisely in the plane of the groove 32. The width 25 of grooves 32 and the profile of groove floors 34 may be used to control this and other aspects of the cleaving process.
In other alternative embodiments (not shown), other characteristics of the grooves 32 may be altered. For example, in the embodiment shown in FIGS. 1 to 3, grooves 32 are of equal depth (e.g., half the diameter of the rod 22 but other values are also possible), however, grooves 32 may have varying depth, for example, grooves 32 at the end of rod 22 may be provided with a smaller groove depth than grooves towards the center of rod 22 in order to, for example, accommodate the decrease in leverage available for bending and cleaving portions of the rod 22 located towards the ends of rod 22.
In still other embodiments (not shown), breakaway sites 24 may be devoid of grooves. For example, breakaway sites 24 may be created by heat treating rod 22 at various locations to create regions where rod 22 is likely to cleave under a bending moment. As another example, rod 22 may be provided in a hollow configuration wherein breakaway sites are formed by areas of rod 22 having a reduced wall thickness.
FIG. 4 shows a cast molding system 100 including a mold 38 having a surface 42 which mirrors an external surface of a component (not shown) to be molded therein. A core 44 is placed in the mold to provide a cavity or other special feature in the component. In order to position the core 44 within the mold, at least one chaplet 14 may be inserted between the core 44 and the mold 38. Specifically, and as shown in FIG. 4, a first chaplet 14 having a first portion 16 configured to engage one of the core 44 and the mold 38 and a second portion 18 configured to engage the other of the core 44 and the mold 38 may be placed under the core 44. A second chaplet 14 is similarly provided over the core 44. As may be appreciated in FIG. 4, the rod 22 of each chaplet 14 extends between the first portion 16 and the second portion 18 without protruding into the core 44 or mold 38.
Accordingly, and as shown in FIG. 5, a method 1000 of positioning a core 44 in a casting mold 38 with a chaplet having a first portion 16, a second portion 18, and a rod 22 extending between the first portion 16 and the second portion 18 can include the steps of measuring 1002 a distance between a surface of the casting mold 38 and a surface of the core 44, reducing 1004 the length of the rod 22 according to the measurement by cleaving the rod 22 along one of a plurality of grooves 32 in the rod 22, inserting 1006 the chaplet between the surface of the casting mold 38 and the surface of the core 44 such that the first portion 16 engages one of the surface of the casting mold 38 and the surface of the core 44 and the second portion 18 engages the other of the surface of the casting mold 38 and the surface of the core 44.
The above-described embodiments are intended to be illustrative in all respects, rather than restrictive, of the present invention. All such variations and modifications are considered to be within the scope and spirit of the present invention as defined by the following claims. No element, act, or instruction used in the description of the present application should be construed as critical or essential to the invention unless explicitly described as such. Also, as used herein, the article “a” is intended to include one or more items.

Claims

What is claimed is:

1. A chaplet comprising:

a first portion configured to engage one of a core and a mold;

a second portion configured to engage the other of said core and said mold;

an elongated rod extending between said first portion and said second portion and having a plurality of breakaway sites for allowing the length of said rod to be selectively reduced in predetermined increments.

2. The chaplet of claim 1, wherein said rod is threaded and in threaded engagement with at least one nut, each said at least one nut associated with one of said first portion and said second portion.

3. The chaplet of claim 2, wherein each said breakaway site includes a groove in said rod.

4. The chaplet of claim 3, wherein each said groove includes a groove floor extending through said rod.

5. The chaplet of claim 4, wherein each said groove floor is approximately equal in length to a diameter of said rod.

6. The chaplet of claim 5, wherein adjacent groove floors are non-parallel.

7. The chaplet of claim 6, wherein adjacent groove floors are perpendicular.

8. The chaplet of claim 7, wherein each said groove defines a plane normal to a longitudinal axis of said rod.

9. The chaplet of claim 1, wherein said first portion is a plate fixed to a first end of said rod and said second portion is a plate having an integral nut portion in threaded engagement with said threaded rod.

10. The chaplet of claim 9, wherein said integral nut portion includes a first tab and a second tab.

11. A system for casting a component of a machine, the system comprising:

a mold having a surface that mirrors an external surface of the component;

a core to be placed in the mold and to provide a cavity in the component;

at least one chaplet to be placed between said mold and said core, said chaplet including a first portion configured to engage one of said core and said mold, a second portion configured to engage the other of said core and said mold, and an elongated rod extending between said first portion and said second portion, said rod having a plurality of breakaway sites distributed along the longitudinal axis thereof for allowing the length of said rod to be selectively reduced in predetermined increments.

12. The system of claim 11, wherein said rod is threaded and in threaded engagement with at least one nut, each at least one nut associated with one of said first portion and said second portion.

13. The system of claim 12, wherein each said break away site is a groove in said rod.

14. The system of claim 13, wherein each said groove includes a groove floor extending through said rod.

15. The system of claim 14, wherein each said groove floor is approximately equal in length to a diameter of said rod.

16. The system of claim 15, wherein adjacent groove floors are non-parallel.

17. The system of claim 16, wherein adjacent groove floors are perpendicular.

18. The system of claim 17, wherein each said groove defines a plane normal to a longitudinal axis of said rod.

19. A method of positioning a core in a casting mold with a chaplet having a first portion, a second portion and a rod extending between said first portion and said second portion, the method comprising:

measuring a distance between a surface of said casting mold and a surface of said core;

reducing said length of said rod according to said measurement by cleaving said rod along one of a plurality of grooves in said rod; and

inserting said chaplet between said surface of said casting mold and said surface of said core such that said first portion engages one of said surface of said casting mold and said surface of said core and said second portion engages said other of said surface of said casting mold and said surface of said core.

20. The method of claim 19, wherein said rod is threaded, at least one of said first portion and said second portion includes an integral nut having a first tab and a second tab, said nut is threaded to said rod, and said inserting further includes rotating one of said first portion, said second portion and said rod to adjust a distance between said first portion and said second portion according to said measurement.