US3241188A

US3241188A - Pressure intensifier

Info

Publication number: US3241188A
Application number: US367907A
Authority: US
Inventors: Paul P Febbo; Jr Ralph P Levey; Herbert A Pohto
Original assignee: Individual
Current assignee: Individual
Priority date: 1964-05-15
Filing date: 1964-05-15
Publication date: 1966-03-22
Anticipated expiration: 1983-03-22

Description

March 22, 1966 p, FEBBQ AL 3,241,188

PRESSURE INTENSIFIER Filed May 15, 1964 3 Sheets-Sheet 1 INVENTORS. Fi 4 Paul P. e

be BY Ralph P. evey, Jr.

Herberf A. Pohfo ATTORNE Y.

P. P. FEBBO ETAL PRESSURE INTENSIFIER March 22, 1966 3 Sheets-Sheet 2 Filed May 15, 1964 INVENTORS.

Paul P. Febbo 5 M m. w

Ralph P. Levey, Jr.

BY Herberf A. Pohfo l ATTORNEY.

March 22, 1966 P. P. FEBBO ETAL 3,241,188

PRESSURE INTENSIFIER Filed May 15, 1964 3 Sheets-Sheet s ATTORNEY.

United States Patent Ofiice 3,241,18 Patented Mat. 22, race 3,241,188 PRESSURE INTENSIFIER Paul P. Febbo, Ralph P. Levey, Jr., and Herbert A. Pohto,

all of Oak Ridge, TemL, assignors t the United States of America as represented by the United States Atomic Energy Commission Filed May 15, 1964, Ser. No. 367,907 6 Claims. (CI. 1 .8-16.5)

This invention relates generally to pressure intensifiers and more particularly to pressure intensifiers which utilize converging anvils to achieve ultra-high pressures.

Prior art intensifiers utilizing converging anvils to develop ultrahigh pressures have typically required rigid structural housings to maintain an exact geometric relationship between the individual anvils. Such a spaced relationship is necessary to enable the anvils to act as free bodies, thereby ensuring a uniform application of pressure to the workpiece. In addition to the inefficiencies resulting from thrust losses due to unnecessary anvil contact, non-uniform anvil loading must be avoided because of the possibility of anvil fracture brought about by concentrations developed as a result of such contact.

The rigid housing member which is characteristic of prior art ultra-high pressure intensifiers which utilize converging anvils, reduces the maximum obtainable pressure amplification in a given external size pressure intensifier. This reduction in attainable pressure amplification results from the reduction in the total external area of the pressure intensifier which is available for exposing the anvils to the source of primary pressure. Since the ratio of the external to internal face surface areas of the anvils largely determines the pressure amplification thereacross, the rigid housing, by reducing the external surface available to the anvils in any given size intensifier, effectively reduces the pressure applied to the workpiece being pressed.

Although higher pressures can be achieved by enlarging the pressure intensifier, such a course is severely limited by the size of existing sources of primary pressure.

It is therefore a general object of the invention to provide a converging anvil type ultra-high pressure intensifier which operates without the use of a rigid housing member.

A further object of the invention is to provide a converging anvil type ultra-high pressure vessel containing an anvil alignment means which does not occupy useful space within a primary pressure vessel.

Other objects of the invention will become apparent from an examination of the following description of the invention and appended drawings wherein:

FIG. 1 is a transverse sectional View of the subject pressure intensifier.

FIG. 2 is a vertical sectional view of the subject pressure intensifier.

FIG. 3 is a detailed plan view of a typical sealing arrangement used in the subject pressure intensifier.

FIG. 4 is a plane view, partially broken away, of the bottom stepped cylinder used in the subject pressure intensifier.

FIG. 5 is a bottom view of a cylindrical segment used in the subject intensifier.

In accordance with the present invention, a pressure intensifier for obtaining pressures in the order of 1,000,000 p.s.i. from a primary source of isostatic pressure in the order of 30,000 p.s.i. is provided. A first group of four converging rams define the four side faces of a cubical pressure chamber. The first group of rams are formed by rigidly mounting four generally frusto-conical anvil members to the flat face portions of four truncated quarter segments of a right cylinder. Two additional converging rams, which define the upper and lower end faces of the cubical pressure chamber, are formed by rigidly mounting a generally frustro-conical anvil member to the smaller end face of each of two stepped cylinders. Radially oriented guides for engaging slots in the ends of the segments are rigidly fixed along the stepped portion of each stepped cylinder. Two adjustable resiliently mounted nylon bolts are provided as vertical alignment means for each truncated cylindrical segment. The bolts are fitted within and protrude from cavities in the stepped portion of the lower stepped cylinder. A thin compliant bag encompasses the entire assembly during a pressing opera tion, thereby substantially permitting the entire primary pressure to be experienced by the outer faces of the truncated cylindrical segments and the stepped cylinders.

To facilitate an understanding of the invention reference is made to FIG. 1 of the drawings wherein a transverse sectional view of a preferred embodiment of the invention is illustrated. Shown in FIG. 1 is a group of converging side rams 1 each comprising a generally frustro-conical anvil member (2, 3, 4 and 5) attached to the planar face of a truncated longitudinal segment of a cylinder (6, 7, 8 and 9, respectively).

Segments

6, 7, 8 and 9 may be obtained by quartering a right solid cylinder longitudinally and truncating each quarter.

Side anvils

2, 3, 4 and 5 are attached to their respective segments by means of a multiplicity of projections 10 spaced about the periphery of the larger face 11 of each anvil member and integrally formed with or rigidly secured to the fiat face 12 of each segment. Set screws 13 are provided in each anvil member. Each anvil member is chamfered at intervals around its periphery so that it terminates in a region of square crosssection of diminishing size as the front face 14 of the anvil is approached. The anvils therefore resemble a regular cone in their larger base portions and a regular, truncated four sided pyramid as their smaller face portions are approached. The square face portions are necessary to reduce the clearance between adjacent anvils during a pressing operation and to define a cubic pressure chamber 15. Also shown are slots 16 which are radially aligned in the centermost portion of the top end of each

segment

6, 7, 8 and 9.

Referring now to FIG. 2, which is a vertical sectional view of the intensifier of FIG. 1, the relationship between the top and bottom stepped

cylinders

17 and 18 respectively, and two of the

cylindrical segments

6 and 8 may be seen. Anvil

members

19 and 20, identical to

anvil members

2, 3, 4 and 5, are attached to top and bottom

stepped cylinders

17 and 18 to form top and

bottom rams

35 and 36 respectively. The smaller face portions 43 of

anvils

19 and 20 form the top and bottom faces of cubic pressure chamber 15.

Top stepped cylinder 17 has appended thereto, on its stepped surface 21 and approximately 90 apart about said surface, four nylon guide members 22 rigidly secured to surface 21 by means of a screw 23 and dowel 24. Bottom stepped cylinder 18 has attached thereto, in a similar manner, four nylon guide members 25 which are also illustrated in FIG. 4. Guide members 25 differ from guide members 22 in that guide members 25 are T-shaped in vertical cross section whereas guide members 22 are rectangular in vertical cross section. The T-shaped members 25, mating in similar shaped, but deeper, slots 26 provided in the bottom of each

cylinder segment

6, 7, 8 and 9 serve both to align

segments

6, 7, 8 and 9 to prevent bottom stepped cylinder 18 from falling away from the remainder of the intensifier assembly when the assembly is lifted by means other than its bottom. The

guides

22 and 25 and

slots

16 and 26 thus cooperatively restrain the side pistons to exclusively convergent or divergent movements. Since only very short distances are traversed by the ram members of the assembly, sufiicient convergent movement of the top and bottom rams is provided for by providing

guides

22 and 25 having a height less than the depths of their

mating slots

16 and 26.

FIG. 3 depicts a typical sealing arrangement of the subject device, Shown in FIG. 3 are adjacent

chamfered surfaces

27 and 28 forming a trough between

segments

6 and 7 into which is fitted a vertical steel sealing member 29 held in place by a strip of adhesive tape 30. Circumferential sealing between the top and side rams is accomplished by a second triangular-eross-section steel sealing member 31 fitted between

adjacent chamfered edges

32 and 33 of top stepped cylinder 17 and

segments

6 and 7. Each junction ,of the vertical sealing member 29 and the circumferential sealing member 31 is covered by an antiextrusion plate 34 held in place wtih adhesive tape 36. Both vertical and

circumferential sealing members

29 and 31 are coated with an insulating plastic along their faces which contact the rams so as to maintain the rams electrically insulated from each other. The sealing arrangement between the bottom and side rams which is similar to that between the top and side rams is also shown in FIG. 3 with hidden lines omitted and with reference numerals corresponding to those used in describing the top and side ram seal.

In operation, the assembled intensifier is inserted into a thin rubber bag 37 as indicated in FIGS. 1 and 2, prior to immersing the assembly in the primary pressure transmitting medium employed in the primary pressure vessel 38. The function of the seals is to prevent extrusion of the rubber bag into the cavities between adjacent pistons which would block movement of the rams. The seals must not, while excluding the rubber bag, substantially inhibit the advancement nor unbalance the thrust of the rams. The triangular cross-section of sealing

members

29 and 31 is designed to introduce minimum resistance to ram movement consistent with sufiicient sealing.

Vertical positioning of

segments

6, 7, 8 and 9 and their attached components is provided for by means of a multiplicity of resiliently-mounted nylon bolts 39, at least two per segment, threadably engaging nuts 40 slidably fitted in a cavity 46 within the stepped portion of bottom stepped cylinder 18. Each bolt 39 protrudes upwardly out of the stepped portion of stepped cylinder 18 a selected amount and is retained at this height by a spring 41. FIG. 4 shows an exploded view, partly in section, of one of the resiliently-mounted bolts 39 together with its associated spring 4-]. and nuts 40. When assembled, each segment of the assembly rests on at least two of these resiliently-mounted protruding bolts 39. By varying the distance by which each bolt protrudes, the supported segment and therefore the attached anvil, may be aligned vertically as well as tilted, as desired, within the range of travel of the bolts. This alignment is accomplished prior to introduction of the specimen to be pressed into chamber 15. The function of springs 41 is to partially set the degree of protrusion of bolts 39 for alignment purposes and to allow retraction of bolts 39 when application of primary pressure causes convergence of the side, top and bottom rams.

FIG. is a bottom view of cylindrical segment 9, identical to

segments

6, 7 and 8 as illustrated in FIGS. 1 and 2. Bearing surfaces 47, which are adapted to rest on the tops of nylon bolts 39 as hereinbefore described, are shown in FIG. 5 together with a T-shaped slot 26 for the reception of a guide member 25.

In a typical pressing operation employing the subject intensifier,

segments

6, 7, 8 and 9, with their anvil mem bers attached, are assembled atop bottom stepped cylinder 1%, T-shaped guide members 25 mating with T-shaped slots 26. Bolts 39 are adjusted to align the convergent faces of the

anvil members

2, 3, 4, 5 and 20 to form five sides of the cubic pressure chamber 15. Into this pressure chamber is positioned a cube of pyrophyllite 42 having contained therein a sample of material to be subjected to ultra-high pressure. Other pressure transmitting materials, such as lithium hydride, talc, or silicones, which are solid at room temperature and pressure and at least semifiuid at working pressures and temperatures; may also be used. Top ram is then lowered into position atop

segments

6, 7, 8 and 9, upper guide members 22 being received into the appropriate slots 16 of segments 6, '7, 8 and 9, and the face 43 of top anvil 19 coming to rest on the aforesaid cube of pyrophyllite. After assembly of the anti-extrusion seals, as previously described, the entire assembly is placed into a close fitting, oil tight rubber bag 37. The bagged intensifier is then immersed in an oil pressure-transmitting-medium of an isostatic pressure vessel 38 and pressed by raising the pressure in the pressure vessel. The pressure in pressure vessel 355 is raised by introducing oil at high pressure through conduit 44 into the annular cavity 45 between the intensifier and primary pressure vessel 38.

The above description of one embodiment of the inven tion was offered for illustrative purposes only and should not be interpreted in a limiting sense. It is intended that the invention be limited only by the claims appended hereto.

What is claimed is:

1. Apparatus for applying ultra-high pressure to a work'- iece encased within a cube-shaped block of pressure transmitting material comprising in combination:

(a) four side rams for horizontally surrounding and converging upon the side faces of said block, each of said side rams having a smaller face section for contacting said block and a larger face sect-ion disposed away from said block for exposure to a source of primary pressure, said side rams having radially oriented vertical slots along their upper and lower peripheries;

(b) an upper ram member for converging upon the top face of said block, said upper ram member having a smaller face section for contacting said block and a larger face section disposed away from said block for exposure to a source of primary pressure;

(c) a lower ram member for converging upon the bottom face of said block, said lower ram member having a smaller section for contacting said block and a larger face section disposed away from said block for exposure to a source of primary pressure;

(d) radially oriented vertical guide members attached to said upper and lower ram members for engaging said radially oriented vertical slots along the upper and lower peripheries of said side rams; and

(e) means for applying isostatic pressure to said larger face portions of said top, bottom and side rams.

2. The apparatus of claim 1 wherein said larger face portions of said top, bottom and side rams substantially define a right circular cylinder.

3. Apparatus for applying ultra-high pressure to a workpiece encased within a cube-shaped block of pressure transmitting material comprising in combination:

(a) four side rams for horizontally surrounding and converging upon the side faces of said block, each of said side rams having a smaller face section for contacting said block and a larger face section disposed away from said block for exposure to a source of primary pressure, said side rams having radially oriented vertical slots along their upper and lower peripheries;

(b) an upper ram member for converging upon the top face of said block, said upper ram member having a smaller face section for contacting said block and a larger face section disposed away from said block I for exposure to a source of primary pressure;

(c) a lower ram member for converging upon the bottom face of said block, said lower ram member having a smaller face section for contacting said block and a larger face section disposed away from said block for exposure to a source of primary pressure;

(d) radially oriented vertical guide members attached to said upper and lower ram members for engaging said radially oriented vertical slots along the upper and lower peripheries of said side rams;

(e) a compliant bag completely enclosing said larger face portions of said top, bottom and side rams; (-f) means for preventing extrusion of said compliant bag between said rams; and

(g) means for applying isostatic pressure to the outer surface of said bag during a pressing operation.

4. Apparatus for applying ultra-high pressure to a workpiece encased within a cube-shaped block of pressure transmit-ting material comprising in combination:

(a) four side anvils for horizontally surrounding and converging upon the side faces of said block, each of said side anvils having a smaller square face sec tion for contacting one side of said block and a larger base section disposed away from said block;

(b) an upper anvil similar in shape to said side anvils for converging upon the top face of said block; (c) a lower anvil similar in slrape to said upper and side anvils for converging upon the bottom face of said block;

(d) four elongated, wedge-shaped cylindrical segments having truncated planar surfaces at their inner ends, the larger base portions of each of said side anvils being rigidly attached to the center of each of said truncated planar surfaces, said segments each having radial-1y oriented vertical slots in their upper and lower ends;

(e) an upper stepped cylinder member having larger and smaller diameter portions, said smaller diameter portion being rigidly attached to the larger base portion of said upper anvil;

(f) a lower stepped cylinder member having larger and smaller diameter portions, said smaller diameter portion being rigidly attached to the larger base portion of said lower anvil;

(g) radially oriented guide means rigidly attached to said upper and lower stepped cylinders for engaging said radially oriented vertical slots in the upper and lower ends of said segments respectively;

(h) a compliant bag completely enclosing the outer surface portion of said cylindrical segments and said top and bottom stepped cylinders when assembled;

(i) means for preventing extrusion of said compliant bag between said segments and between said stepped cylinders and said segments; and

(j) means for applying isostatic pressure to the outer surface of said bag during a pressing operation.

5. Apparatus for applying ultra-high pressure to a workpiece encased within a cube-shaped block of pressure transmitting material comprising in combination:

(a) four side anvils for horizontally surrounding and converging upon the side faces of said block, each of said side anvils having a smaller square face section for contacting one side of said block and a large base section disposed away from said block;

(b) an upper anvil similar in shape to said side anvils for converging upon the top face of said block;

(c) a lower anvil similar in shape to said upper side anvils for converging upon the bottom face of said block;

(d) (four elongated, wedge-shaped cylindrical segments having truncated planr surfaces at their inner ends, the larger base portions of each of said side anvils being rigidly attached to the center of each of said truncated planar surfaces, each of said segments having radially oriented vertical slots in their upper and lower ends;

(e) an upper stepped cylinder member having larger and smaller diameter portions, said smaller diameter portion being rigidly attached to the larger base portion or said upper anvil;

(f) a lower stepped cylinder member having larger and smaller diameter portions, said smaller diameter portion being rigidly attached to the large base portion of said lower anvil;

(h) means for providing vertical alignment of said cylindrical segments;

(i) a compliant bag completely enclosing the outer surface portion of said cylindrical segments and said top and bottom stepped cylinders when assembled;

(j) means for preventing extrusion of said compliant bag between said segments and between said stepped cylinders and said segments; and

(k) means for applying isostatic pressure to the outer surface of said bag during a pressing operation.

6. The apparatus of claim 5 wherein said means for providing vertical alignment of said cylindrical segments comprises adjustable, resiliently mounted bolts protruding from cavities within said bottom stepped cylinder, at least two of said bolts being provided for each of said cylindrical segments.

References Cited by the Examiner UNITED STATES PATENTS 3,103,699 9/1963 Gerard et al. 3,118,177 1/1964 Von Platen. 3,150,142 9/1964 Newhall. 3,169,273 2/1965 Brayman. 3,179,979 4/ 1965 Bundy et al.

WILLIAM J. STEPHENSON, Primary Examiner.

Claims

1. APPARATUS FOR APPLYING ULTRA-HIGH PRESSURE TO A WORKPIECE ENCASED WITHIN A CUBE-SHAPED BLOCK OF PRESSURE TRANSMITTING MATERIAL COMPRISING IN COMBINATION: (A) FOUR SIDE RAMS FOR HORIZONTALLY SURROUNDING AND CONVERGING UPON THE SIDE FACES OF SAID BLOCK, EACH OF SAID SIDE RAMS HAVING A SMALLER FACE SECTION FOR CONTACTING SAID BLOCK AND A LARGER FACE SECTION DISPOSED AWAY FROM SAID BLOCK FOR EXPOSURE TO A SOURCE OF PRIMARY PRESSURE, SAID SIDE RAMS HAVING RDIALLY ORIENTED VERTICAL SLOTS ALONG THEIR UPPER AND LOWER PERIPHERIES; (B) AN UPPER RAM MEMBER FOR CONVERGING UPON THE TOP FACE OF SAID BLOCK, SAID UPPER RAM MEMBER HAVING A SMALLER FACE SECTION FOR CONTACTING SAID BLOCK AND A LARGER FACE SECTION DISPOSED AWAY FROM SAID BLOCK FOR EXPOSURE TO A SOURCE OF PRIMARY PRESSURE; (C) A LOWER RAM MEMBER FOR CONVERGING UPON THE BOTTOM FACE OF SAID BLOCK, SAID LOWER RAM MEMBER HAVING A SMALLER SECTION FOR CONTACTING SAID BLOCK AND A LARGER FACE SECTION DISPOSED AWAY FROM SAID BLOCK FOR EXPOSURE TO A SOURCE OF PRIMARE PRESSURE; (D) RADIALLY ORIENTED VERTICAL GUIDE MEMBERS ATTACHED TO SAID UPPER AND LOWER RAM MEMBRS FOR ENGAGING SAID RADIALLY ORIENTED VERTICAL SLOTS ALONG THE UPPER AND LOWER PERIPHERIES OF SAID SIDE RAMS; AND (E) MEANS FOR APPLY ISOSTATIC PRESSURE TO SAID LARGER FACE PORTIONS OF SAID TOP, BOTTOM AND SIDE RAMS.