CA1049299A - Ultrahigh pressure apparatus - Google Patents
Ultrahigh pressure apparatusInfo
- Publication number
- CA1049299A CA1049299A CA243,012A CA243012A CA1049299A CA 1049299 A CA1049299 A CA 1049299A CA 243012 A CA243012 A CA 243012A CA 1049299 A CA1049299 A CA 1049299A
- Authority
- CA
- Canada
- Prior art keywords
- die
- hollow cylinder
- punches
- gaskets
- steel
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
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Abstract
ABSTRACT OF THE DISCLOSURE
An ultrahigh pressure apparatus having a pair of opposed frustoconical punches, an annular steel die disposed between said punches and having a stepped cylindrical aperture coaxially aligned with the punches, a hollow cylinder of rigid material having a small compressibility coefficient located in the die cylinder aperture, and a pair of gaskets, larger in outer diameter than the hollow cylinder, mating with stepped outer portion of the die cylindrical aperture wall. Preferably the steel die is of die steel or high speed steel; the punches are of a sintered WC-Co alloy; the hollow cylinder is of pore-free sintered alumina; and the gaskets are of a sintered aggalmatoric stone. Advantages of the structure over conventional dies include improved yields per run and faster reformation following plastic deformation through use.
An ultrahigh pressure apparatus having a pair of opposed frustoconical punches, an annular steel die disposed between said punches and having a stepped cylindrical aperture coaxially aligned with the punches, a hollow cylinder of rigid material having a small compressibility coefficient located in the die cylinder aperture, and a pair of gaskets, larger in outer diameter than the hollow cylinder, mating with stepped outer portion of the die cylindrical aperture wall. Preferably the steel die is of die steel or high speed steel; the punches are of a sintered WC-Co alloy; the hollow cylinder is of pore-free sintered alumina; and the gaskets are of a sintered aggalmatoric stone. Advantages of the structure over conventional dies include improved yields per run and faster reformation following plastic deformation through use.
Description
The present invention relates to an ultrahigh pre-ssure apparatus, particularly to improvements in such appar-atus invented by the Inventor in use of a hollow cylinder made of a rigid material with a small compressibility coefficient.
It is desired generally in works under high pressure to increase the length of a reaction chamber arranged in such apparatus, axially as well as radially for enlarged amount of reaction charges per run, or for widened reaction zone which has favorable temperature conditions for reaction.
But increasing the axial length of the reaction cham-ber disadvantageously results in an increased thickness at seal-ing part of gaskets, which are placed in a high pressure cham-ber, or a space surrounded by the punches and the die. Since the sealing ability of gaskets decreases in inverse proportion to their thickness and increases in proportion to the length of the sealing part, it is necessary that such decrease caused ; by the increased thickness, be set off by increasing the length.
It is also desired for a large scale high pressure apparatus that members should be made of some kind of strong steels, high speed steel or die steel, for example, for reasonable manufacturing.
A dle so made suffers in general from plastic deforma-tions much or less caused at the inner wall after several repeat-ed runs even in use of a hollow cylinder for reducing the stress transmitted to the die. Thus reformation are required of the die for a tight contact of the hollow cylinder with the die, by cutting or grinding away such deformations at an inter-val for a smooth surface of the inner wall. And such reforma-tion should be made on all the surface of the inner wall of the die. Further the press load to be applied should be re-determined due to the changes in compressing section by reformation, and modification is also required of dimensions c~/ - 1 - ' ~
of elements for reaction.
The present invention is broadly defined as an ultra-high pressure apparatus for diamond synthesis or the like which comprises: a pair of opposed frusto-conical punches with a flat end surface; an annular die made of steel and placed between the punches, which die has a cylindrical aperture co-axially arranged with the punches; a hollow cylinder made of sintered alumina to be free of pores having an inner diameter substantially equal to the diameter of the flat end surface;
a pair of gaskets adjacent to each outer portion of the inner wall of the die and has an inner diameter same with that of the hollow cylinder and a larger outer diameter than that of the latter; the die having at the middle portion thereof a substantially concentric cylindrical projection of an axial length equal to that of the hollow cylinder so that the bore is tightly fitted to the gaskets and the hollow cylinder.
In a specific aspect of the invention, a metal collar generally adjacent to the said hollow cylinder is inserted between facing walls of the die and said cylinder. In a further specific aspect of the invention the collar is formed of several sections.
This invention is to proyide an ultrahigh pressure apparatus of an industrial scale which is well workable and free from the above said problems.
The features and advantages of the invention will be better understood from the following description, taken in connection with the accompanying drawing, in which:
Figure 1 is an elevational section view of the main part of a conventional ultrahigh pressure apparatus in use of the hollow cylinder;
Figure 2 is an elevational view of the main part of an apparatus embodying this invention which shows its cb/ - 2 -104g299 section;
Figure 3 is an elevational sectional view of the main part of one of the most preferred embodiment of the invention;
Figure 4 is an elevational sectional view of the main part of another embodiment of the invention; and Figure 5 is a horizontal sectional view of the embodiment in Figure 4 as exploded at A-A, showing only a me'cal collar, a hollow cylinder, a reaction chamber and a refractory tube surrounding the chamber.
In Figure 1, an annular die (3) of a steel, such as die steel or high speed steel, is placed between a pair of opposed punches ~1, 2), which are made of a very hard alloy such as a sintered WC-Co alloy. Adjacent to the inner wall of the die (3) is placed a hollow cylinder (4), made of alumina sintered to be almost free from pores. A refractory . .
tube (5) surrounds a reaction chamber (6), and tablets ~7, 8) are for thermal and electric insulation and are made of a rigidly fired refractory. For electric conductance steel rings 20 (9, 10) and terminal plates (11, 12) are arranged. Gaskets (13, 14) are of a sintered aggalmatoric stone.
Of Figures 2, 3 and 4, which illustrate some embodi-ments of the invention, Figure 2 exemplifies an arrangement for a comparatively small apparatus in use of a hollow cylinder which has a smaller outer diameter. Figures 3 and 4 are for a comparatively large apparatus in use of such cylinder which has a larger outer diameter.
The arrangement in Figure 3 or 4 shows a hollow cylinder with tapered ends facing to the flank or punches.
The tapered ends are provided on the cylinder for increasing a stress support for the cylinder against the deformation under high pressures generated in a reaction chamber; for cb/ ~ 3 -improving the sealing ability of gaskets for the pressures, by reducing its gradients within the gaskets adjacent to the flank of punches; and for protection of punches from breakup.
In Figures 2 to 4, an annular die (17), made of a steel such as die steel or high speed steel, is placed between and coaxially with a pair of opposed punches (15, 16), which are made of a sintered WC-Co alloy. Adjacent to the inner wall of the die (17) is placed a hollow cylinder (18), which is made of alumina sintered to be almost free from pores.
A refractory tube (19~ surrounds a reaction chamber (20).
Tablets (21, 22) of a rigidly fired refractory are arranged for tllermal and electric insulation, and steel rings (23, 24) and terminal plates (25, 26) are for electric conductance.
Gaskets ~27, 28) are a sintered aggalmatoric stone, by material.
The punches (15, 16) have a protector ~29, 30) on them in the arrangement of Figures 3 and 4.
For numeric example, with reference to the arrange-ment of Figure 2, the punches have a flat end of 20 mm by diameter, and are axially tapered at 33. The die has a stepped aperture of 30 mm and 34 mm by diameter at the por-tions adjacent to the hollow cylinder and to the gaskets, res-pectively. The cylinder is 20 mm by inner diameter and 10 mm high. Gaskets, larger in outer diameter than the cylinder of sintered alumina, are placed adjacent to the inner wall of a die.
Figure 5 illustrates a section of the arrangement in Figure 4, as exploded at A-A, showing only a metal collar, a reaction chamber, and a refractory tube that surrounds such chamber. In this figure, such collar are formed of four quarter-circles (31a~d), while in Figure 4 it is inte-grally formed.
Referring to the arrangement in Figure 3, the - cb/ 4 punches have a flat end 75 mm across and axially tapered at 36. The die has a stepped aperture, which is 165 mm and 185 mm by inner diameter at the portions adjacent to the cylinder and to the gaskets, respectively. The cylinder is 100 mm high and 75 mm by inner diameter. The protectors for punches are a mild steel plate whic'n is about 2 mm thick, and are tightly placed on them.
In a numeric example of the arrangement shown in Figure 4, the punches have a flat end 75 mm across and are axially tapered at 36. The die has a stepped aperture, and is 165 mm and 185 mm by inner diameter at the portions adjacent to the hollow cylinder and to the gaskets, respectively. The cylinder is 100 mm high and is 75 mm by inner diameter. The protectors for the punches are a mild steel plate about 2 mm thick and are tightly placed on them. The larger end of pro-tectors has a diameter larger than the aperture of the die in each of Figures 3 and 4 and according to any embodiment of this invention, the gaskets larger in outer diameter than the hollow cylinder of sintered alumina, are placed adjacent to t'ne inner wall of the die.
As might be understood from the above description about some embodiments of the invention with reference to the drawing, the apparatus according to this invention has per-mitted of several functions and advantages to conventional ones, by using gaskets which are larger in outer diameter than the hollow cylinder and are placed adjacent to the inner wall of the die at the enlarged portion.
According to this invention, gaskets, larger in outer diameter than the hollow cylinder, are used adjacent to the end portions of the inner wall of the die.
With an increased length of the sealing portion as compared with conventional apparatus, this invention has cb/
permitted to use sufficiently thick gaskets for extending the height of a reaction chamber and for increasing compressive strokes, thus improving in yields per run.
Conventionally it has been required to increase press loads for compression according to the enlargement of the aper-ture caused by reformation. While, this invention has permitted of stable works in use of unchanged press loads, regardless of such enlar $ent of the aperture at the portion adjacent to the hollow cylinder, for, since the inner diameter of the die remains unchanged at the shoulder, the compressive forces are divided at a substantially unchanged ratio for materials of the reaction chamber from the flat ends of punches and for the hollow cylinder through gaskets from the flanks of punches.
Conventionally it has been further required to modify the dimension of gaskets in outer diameter to fit an enlarged i aperture of the die. Such modification is unnecessary accord-ing to this invention, and each element for reaction is very simply machined and manufactured.
Quick reformation is attainable of the die according to the invention, since such reformation is required only at the portion adjacent to the hollow cylinder, while, in contrast, reformation has been required from end to end of the inner wall of a conventional die.
In placing elements for reaction within the aperture of a die, they are readily positioned according to the inven-tion, since the cylindrical projection of a die is axially as long as a hollow cylinder adjacent to it.
An apparatus embodying the invention, in which a metal collar is used adjacent to the facing walls of a die and a hollow cylinder of an axial length,has an extended life as compared with conventional ones out of use of such collar, for, since such collar can be taken out of the die for exchange, cb/ - 6 -~04szas the die remains workable even when the collar gets unsuitable for use due to enlarged aperture by reformation or due to break-up after repeated runs.
When the collar is formed of several sections, damaged ones alone are required to be taken out for exhange, thus reducing compensation of expensive collar.
In comparison of workabilities in use of apparatus conventionally designed and according to this invention, both comprising an annular die which is 165 mm by inner dia-meter, reaction charges were treated according to the invention, twice as much as the conventional one could, with requirement of press load larger than the latter by about 10%. No differ-ence was appreciated in lives of the dies.
., cb/ _ 7
It is desired generally in works under high pressure to increase the length of a reaction chamber arranged in such apparatus, axially as well as radially for enlarged amount of reaction charges per run, or for widened reaction zone which has favorable temperature conditions for reaction.
But increasing the axial length of the reaction cham-ber disadvantageously results in an increased thickness at seal-ing part of gaskets, which are placed in a high pressure cham-ber, or a space surrounded by the punches and the die. Since the sealing ability of gaskets decreases in inverse proportion to their thickness and increases in proportion to the length of the sealing part, it is necessary that such decrease caused ; by the increased thickness, be set off by increasing the length.
It is also desired for a large scale high pressure apparatus that members should be made of some kind of strong steels, high speed steel or die steel, for example, for reasonable manufacturing.
A dle so made suffers in general from plastic deforma-tions much or less caused at the inner wall after several repeat-ed runs even in use of a hollow cylinder for reducing the stress transmitted to the die. Thus reformation are required of the die for a tight contact of the hollow cylinder with the die, by cutting or grinding away such deformations at an inter-val for a smooth surface of the inner wall. And such reforma-tion should be made on all the surface of the inner wall of the die. Further the press load to be applied should be re-determined due to the changes in compressing section by reformation, and modification is also required of dimensions c~/ - 1 - ' ~
of elements for reaction.
The present invention is broadly defined as an ultra-high pressure apparatus for diamond synthesis or the like which comprises: a pair of opposed frusto-conical punches with a flat end surface; an annular die made of steel and placed between the punches, which die has a cylindrical aperture co-axially arranged with the punches; a hollow cylinder made of sintered alumina to be free of pores having an inner diameter substantially equal to the diameter of the flat end surface;
a pair of gaskets adjacent to each outer portion of the inner wall of the die and has an inner diameter same with that of the hollow cylinder and a larger outer diameter than that of the latter; the die having at the middle portion thereof a substantially concentric cylindrical projection of an axial length equal to that of the hollow cylinder so that the bore is tightly fitted to the gaskets and the hollow cylinder.
In a specific aspect of the invention, a metal collar generally adjacent to the said hollow cylinder is inserted between facing walls of the die and said cylinder. In a further specific aspect of the invention the collar is formed of several sections.
This invention is to proyide an ultrahigh pressure apparatus of an industrial scale which is well workable and free from the above said problems.
The features and advantages of the invention will be better understood from the following description, taken in connection with the accompanying drawing, in which:
Figure 1 is an elevational section view of the main part of a conventional ultrahigh pressure apparatus in use of the hollow cylinder;
Figure 2 is an elevational view of the main part of an apparatus embodying this invention which shows its cb/ - 2 -104g299 section;
Figure 3 is an elevational sectional view of the main part of one of the most preferred embodiment of the invention;
Figure 4 is an elevational sectional view of the main part of another embodiment of the invention; and Figure 5 is a horizontal sectional view of the embodiment in Figure 4 as exploded at A-A, showing only a me'cal collar, a hollow cylinder, a reaction chamber and a refractory tube surrounding the chamber.
In Figure 1, an annular die (3) of a steel, such as die steel or high speed steel, is placed between a pair of opposed punches ~1, 2), which are made of a very hard alloy such as a sintered WC-Co alloy. Adjacent to the inner wall of the die (3) is placed a hollow cylinder (4), made of alumina sintered to be almost free from pores. A refractory . .
tube (5) surrounds a reaction chamber (6), and tablets ~7, 8) are for thermal and electric insulation and are made of a rigidly fired refractory. For electric conductance steel rings 20 (9, 10) and terminal plates (11, 12) are arranged. Gaskets (13, 14) are of a sintered aggalmatoric stone.
Of Figures 2, 3 and 4, which illustrate some embodi-ments of the invention, Figure 2 exemplifies an arrangement for a comparatively small apparatus in use of a hollow cylinder which has a smaller outer diameter. Figures 3 and 4 are for a comparatively large apparatus in use of such cylinder which has a larger outer diameter.
The arrangement in Figure 3 or 4 shows a hollow cylinder with tapered ends facing to the flank or punches.
The tapered ends are provided on the cylinder for increasing a stress support for the cylinder against the deformation under high pressures generated in a reaction chamber; for cb/ ~ 3 -improving the sealing ability of gaskets for the pressures, by reducing its gradients within the gaskets adjacent to the flank of punches; and for protection of punches from breakup.
In Figures 2 to 4, an annular die (17), made of a steel such as die steel or high speed steel, is placed between and coaxially with a pair of opposed punches (15, 16), which are made of a sintered WC-Co alloy. Adjacent to the inner wall of the die (17) is placed a hollow cylinder (18), which is made of alumina sintered to be almost free from pores.
A refractory tube (19~ surrounds a reaction chamber (20).
Tablets (21, 22) of a rigidly fired refractory are arranged for tllermal and electric insulation, and steel rings (23, 24) and terminal plates (25, 26) are for electric conductance.
Gaskets ~27, 28) are a sintered aggalmatoric stone, by material.
The punches (15, 16) have a protector ~29, 30) on them in the arrangement of Figures 3 and 4.
For numeric example, with reference to the arrange-ment of Figure 2, the punches have a flat end of 20 mm by diameter, and are axially tapered at 33. The die has a stepped aperture of 30 mm and 34 mm by diameter at the por-tions adjacent to the hollow cylinder and to the gaskets, res-pectively. The cylinder is 20 mm by inner diameter and 10 mm high. Gaskets, larger in outer diameter than the cylinder of sintered alumina, are placed adjacent to the inner wall of a die.
Figure 5 illustrates a section of the arrangement in Figure 4, as exploded at A-A, showing only a metal collar, a reaction chamber, and a refractory tube that surrounds such chamber. In this figure, such collar are formed of four quarter-circles (31a~d), while in Figure 4 it is inte-grally formed.
Referring to the arrangement in Figure 3, the - cb/ 4 punches have a flat end 75 mm across and axially tapered at 36. The die has a stepped aperture, which is 165 mm and 185 mm by inner diameter at the portions adjacent to the cylinder and to the gaskets, respectively. The cylinder is 100 mm high and 75 mm by inner diameter. The protectors for punches are a mild steel plate whic'n is about 2 mm thick, and are tightly placed on them.
In a numeric example of the arrangement shown in Figure 4, the punches have a flat end 75 mm across and are axially tapered at 36. The die has a stepped aperture, and is 165 mm and 185 mm by inner diameter at the portions adjacent to the hollow cylinder and to the gaskets, respectively. The cylinder is 100 mm high and is 75 mm by inner diameter. The protectors for the punches are a mild steel plate about 2 mm thick and are tightly placed on them. The larger end of pro-tectors has a diameter larger than the aperture of the die in each of Figures 3 and 4 and according to any embodiment of this invention, the gaskets larger in outer diameter than the hollow cylinder of sintered alumina, are placed adjacent to t'ne inner wall of the die.
As might be understood from the above description about some embodiments of the invention with reference to the drawing, the apparatus according to this invention has per-mitted of several functions and advantages to conventional ones, by using gaskets which are larger in outer diameter than the hollow cylinder and are placed adjacent to the inner wall of the die at the enlarged portion.
According to this invention, gaskets, larger in outer diameter than the hollow cylinder, are used adjacent to the end portions of the inner wall of the die.
With an increased length of the sealing portion as compared with conventional apparatus, this invention has cb/
permitted to use sufficiently thick gaskets for extending the height of a reaction chamber and for increasing compressive strokes, thus improving in yields per run.
Conventionally it has been required to increase press loads for compression according to the enlargement of the aper-ture caused by reformation. While, this invention has permitted of stable works in use of unchanged press loads, regardless of such enlar $ent of the aperture at the portion adjacent to the hollow cylinder, for, since the inner diameter of the die remains unchanged at the shoulder, the compressive forces are divided at a substantially unchanged ratio for materials of the reaction chamber from the flat ends of punches and for the hollow cylinder through gaskets from the flanks of punches.
Conventionally it has been further required to modify the dimension of gaskets in outer diameter to fit an enlarged i aperture of the die. Such modification is unnecessary accord-ing to this invention, and each element for reaction is very simply machined and manufactured.
Quick reformation is attainable of the die according to the invention, since such reformation is required only at the portion adjacent to the hollow cylinder, while, in contrast, reformation has been required from end to end of the inner wall of a conventional die.
In placing elements for reaction within the aperture of a die, they are readily positioned according to the inven-tion, since the cylindrical projection of a die is axially as long as a hollow cylinder adjacent to it.
An apparatus embodying the invention, in which a metal collar is used adjacent to the facing walls of a die and a hollow cylinder of an axial length,has an extended life as compared with conventional ones out of use of such collar, for, since such collar can be taken out of the die for exchange, cb/ - 6 -~04szas the die remains workable even when the collar gets unsuitable for use due to enlarged aperture by reformation or due to break-up after repeated runs.
When the collar is formed of several sections, damaged ones alone are required to be taken out for exhange, thus reducing compensation of expensive collar.
In comparison of workabilities in use of apparatus conventionally designed and according to this invention, both comprising an annular die which is 165 mm by inner dia-meter, reaction charges were treated according to the invention, twice as much as the conventional one could, with requirement of press load larger than the latter by about 10%. No differ-ence was appreciated in lives of the dies.
., cb/ _ 7
Claims (3)
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. An ultrahigh pressure apparatus for diamond synthesis or the like which comprises:
1) a pair of opposed frusto-conical punches with a flat end surface;
2) an annular die made of steel and placed between said punches, which die has a cylindrical aper-ture coaxially arranged with the punches;
3) a hollow cylinder made of sintered alumina to be free of pores having an inner diameter substantially equal to the diameter of the flat end surface;
4) a pair of gaskets adjacent to each outer portion of the inner wall of the die, each said gasket having an inner diameter same with that of the hollow cylinder and a larger outer diameter than that of the hollow cylinder, said die having at the middle portion thereof a substantially concentric cylindrical projection of an axial length equal to that of the hollow cylinder so that the bore is tightly fitted to the gaskets and the hollow cylinder.
1) a pair of opposed frusto-conical punches with a flat end surface;
2) an annular die made of steel and placed between said punches, which die has a cylindrical aper-ture coaxially arranged with the punches;
3) a hollow cylinder made of sintered alumina to be free of pores having an inner diameter substantially equal to the diameter of the flat end surface;
4) a pair of gaskets adjacent to each outer portion of the inner wall of the die, each said gasket having an inner diameter same with that of the hollow cylinder and a larger outer diameter than that of the hollow cylinder, said die having at the middle portion thereof a substantially concentric cylindrical projection of an axial length equal to that of the hollow cylinder so that the bore is tightly fitted to the gaskets and the hollow cylinder.
2. An ultrahigh pressure apparatus as claimed in claim 1, in which said die consists of a base which has a substantially straight cylindrical bore of a diameter equal to the outer diameter of the gaskets and a cylindrical collar body of a metallic material.
3. An ultrahigh pressure apparatus as claimed in claim 2, in which said cylindrical collar body consists of a plurality of radial segments.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA243,012A CA1049299A (en) | 1976-01-06 | 1976-01-06 | Ultrahigh pressure apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA243,012A CA1049299A (en) | 1976-01-06 | 1976-01-06 | Ultrahigh pressure apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1049299A true CA1049299A (en) | 1979-02-27 |
Family
ID=4104906
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA243,012A Expired CA1049299A (en) | 1976-01-06 | 1976-01-06 | Ultrahigh pressure apparatus |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1049299A (en) |
-
1976
- 1976-01-06 CA CA243,012A patent/CA1049299A/en not_active Expired
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