US3210837A - Method of effecting pre-stress - Google Patents
Method of effecting pre-stress Download PDFInfo
- Publication number
- US3210837A US3210837A US327236A US32723663A US3210837A US 3210837 A US3210837 A US 3210837A US 327236 A US327236 A US 327236A US 32723663 A US32723663 A US 32723663A US 3210837 A US3210837 A US 3210837A
- Authority
- US
- United States
- Prior art keywords
- stress
- yokes
- pillars
- construction
- forces
- 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 - Lifetime
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Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B30—PRESSES
- B30B—PRESSES IN GENERAL
- B30B15/00—Details of, or accessories for, presses; Auxiliary measures in connection with pressing
- B30B15/04—Frames; Guides
- B30B15/042—Prestressed frames
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B31/00—Rolling stand structures; Mounting, adjusting, or interchanging rolls, roll mountings, or stand frames
- B21B31/02—Rolling stand frames or housings; Roll mountings ; Roll chocks
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21B—ROLLING OF METAL
- B21B31/00—Rolling stand structures; Mounting, adjusting, or interchanging rolls, roll mountings, or stand frames
- B21B31/02—Rolling stand frames or housings; Roll mountings ; Roll chocks
- B21B31/028—Prestressing of rolls or roll mountings in stand frames
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49758—During simulated operation or operating conditions
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49826—Assembling or joining
- Y10T29/49863—Assembling or joining with prestressing of part
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49826—Assembling or joining
- Y10T29/49908—Joining by deforming
- Y10T29/49925—Inward deformation of aperture or hollow body wall
- Y10T29/49927—Hollow body is axially joined cup or tube
Definitions
- a pressure means is necessary, which with support against the construction in question is charged with great force, which is thereby transmitted to the construction and compresses its parts so that the desired pre-stress is obtained.
- the pre-stress is effected thus by tightening or stretching the pressure means at erection until the parts of the construction are compressed with sufiiciently great force.
- This procedure is suitable in such cases where use is made of simple pressure means such as tension rods, draw bolts or the like.
- the method is on the other hand detailed and difficult to execute in such cases where other pressure means are used, for example strip or thread casings wound around the construction.
- the method according to the present invention is especially suitable for such cases, since the construction may be at first built up without pre-stress or with very little pre-stress. Further, the method should be used to pre-stress or to obtain an increased pre-stress in composed constructions, which are normally subject to an intermittent working load, such as for example press frames, rolling stands and motor frames, whereby according to the invention the construction is loaded with a force being at least equal to the desired pre-stress and adapted to charge the construction in a way statically imitating said normal working load, so that a clearance occurs between at least two of the parts of the composed construction, after which filling pieces are inserted in said clearance.
- an intermittent working load such as for example press frames, rolling stands and motor frames
- the method according to the invention leads to a considerable simplification of the manufacture.
- Such frames have namely been manufactured previously by winding a steel strip or the like under heavy drawing pressure in several layers around pillars and yokes but this known procedure necessitates an expensive apparatus and is both detailed and costly.
- the pre-stress can no longer be regulated, but according to the method according to the invention the pre-stress in such a frame may easily be increased to a higher value if for some reason it is too low.
- FIGURE 1 shows a frame including two semi-circular yokes 1 and 2 separated by two pillars 3 and 4 and held 3,210,837 Patented Oct. 12, 1965 together by a strip casing 5 wound around yokes and pillars.
- the frame in FIGURE 1 is erected without any real pre-stress and in order to obtain pre-stress in the frame, which is necessary if the frame shall be able to take up forces without clearance arising between its parts, the frame is charged with two forces P and P parallel with the pillars and working towards the yokes. These forces which are equal and directed in opposite directions are symbolised in FIGURE 2 by two arrows.
- the forces P and P should be at least equal to the desired pre-stress in the frame, but preferably considerably greater in order that the desired pre-stress can with certainty be attained.
- the method according to the invention may be adapted to all kinds of prestressed, composed constructions irrespective of which form the pressure means has.
- the adaptation of the method is thus not limited to the shown type with pressure means in the form of a thread or strip casing but several variations are feasible within the scope of the following claims.
- Method of effecting a desired degree of pre-stress in a construction comprising a plurality of pillars separating a pair of yokes at opposite ends of a surrounding strip casing, said method including the steps of applying equal forces in opposite directions to said yokes to stretch said casing and give it a stress at least equal to the desidered pre-stress, thereby providing clearances between said yokes and the end of said pillars, then inserting fillers to substantially fill each of said clearances and removing said forces, said fillers thereby retaining the construction in extended pre-stressed condition.
- Method of producing a pre-stressed frame construction comprising a pair of yokes separated by a plurality of intermediate pillars and a clamping means surrounding said yokes and pillars, said method including the steps of fitting said yokes and pillars loosely in said surrounding clamping means, applying equal forces in opposite directions to said yokes to stretch said clamping means and give it a stress at least equal to the desired final pre-stress, thereby providing clearance between said yokes and the end of said pillars, then inserting fillers to substantially fill each of said clearances, and removing said forces, said fillers thereby retaining the construction in extended pre-stressed condition.
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Metal Rolling (AREA)
- Placing Or Removing Of Piles Or Sheet Piles, Or Accessories Thereof (AREA)
Description
Oct. 12, 1965 A. HASSELLOF 3,210,837
METHOD OF EFFEC'IING PRE-STRESS Filed Dec. 2, 1963 1N ENTOR 44% 62 55543;
United States Patent 3,210,837 H METHOD OF EFFECTING PRE-STRESS Alke Hassellof, Surahammar, Sweden, assignor to Allmanna Svenska Elcktriska Aktie'bolaget, Vasteras, Sweden, :1 Swedish corporation Filed Dec. 2, 1963, Ser. No. 327,236 Claims priority, application Sweden, Dec. 5, 1962, 13,081/ 62 2 Claims. (Cl. 29404) The present invention relates to a method of effecting pre-stress or increasing the pre-stress in composed constructions and to pre-streissed constructions manufactured or adapted to increased pre-stress in accordance with this method.
In order to effect pre-stressed constructions a pressure means is necessary, which with support against the construction in question is charged with great force, which is thereby transmitted to the construction and compresses its parts so that the desired pre-stress is obtained. The pre-stress is effected thus by tightening or stretching the pressure means at erection until the parts of the construction are compressed with sufiiciently great force. This procedure is suitable in such cases where use is made of simple pressure means such as tension rods, draw bolts or the like. The method is on the other hand detailed and difficult to execute in such cases where other pressure means are used, for example strip or thread casings wound around the construction.
The method according to the present invention is especially suitable for such cases, since the construction may be at first built up without pre-stress or with very little pre-stress. Further, the method should be used to pre-stress or to obtain an increased pre-stress in composed constructions, which are normally subject to an intermittent working load, such as for example press frames, rolling stands and motor frames, whereby according to the invention the construction is loaded with a force being at least equal to the desired pre-stress and adapted to charge the construction in a way statically imitating said normal working load, so that a clearance occurs between at least two of the parts of the composed construction, after which filling pieces are inserted in said clearance.
Especially for such pre-stressed frames which include two substantially semi-circular yokes separated by two pillars and held together by a prestressed thread or strip casing wound around the yokes and pillars, the method according to the invention leads to a considerable simplification of the manufacture. Such frames have namely been manufactured previously by winding a steel strip or the like under heavy drawing pressure in several layers around pillars and yokes but this known procedure necessitates an expensive apparatus and is both detailed and costly. After the winding of the strip casing has been carried out the pre-stress can no longer be regulated, but according to the method according to the invention the pre-stress in such a frame may easily be increased to a higher value if for some reason it is too low.
The invention will be described in more detail in the following with reference to the accompanying figures which show schematically how the method is adapted to a frame of the type described above.
FIGURE 1 shows a frame including two semi-circular yokes 1 and 2 separated by two pillars 3 and 4 and held 3,210,837 Patented Oct. 12, 1965 together by a strip casing 5 wound around yokes and pillars. The frame in FIGURE 1 is erected without any real pre-stress and in order to obtain pre-stress in the frame, which is necessary if the frame shall be able to take up forces without clearance arising between its parts, the frame is charged with two forces P and P parallel with the pillars and working towards the yokes. These forces which are equal and directed in opposite directions are symbolised in FIGURE 2 by two arrows. The forces P and P should be at least equal to the desired pre-stress in the frame, but preferably considerably greater in order that the desired pre-stress can with certainty be attained. When the non-stressed frame according to FIGURE 1 is charged by the above-named forces the strip casing 5 is stretched and a clearance 6 occurs between the upper yoke 1 and the pillars 3 and 4. In these clearances one or several filling pieces 7 are placed, which retain the frame in the extended position according to FIGURE 2 even after the forces P and P have been removed. The pressure in the strip casing 5 then also remains substantially unchanged and the desired pre-stress has thereby been obtained.
The method according to the invention may be adapted to all kinds of prestressed, composed constructions irrespective of which form the pressure means has. The adaptation of the method is thus not limited to the shown type with pressure means in the form of a thread or strip casing but several variations are feasible within the scope of the following claims.
I claim:
1. Method of effecting a desired degree of pre-stress in a construction comprising a plurality of pillars separating a pair of yokes at opposite ends of a surrounding strip casing, said method including the steps of applying equal forces in opposite directions to said yokes to stretch said casing and give it a stress at least equal to the desidered pre-stress, thereby providing clearances between said yokes and the end of said pillars, then inserting fillers to substantially fill each of said clearances and removing said forces, said fillers thereby retaining the construction in extended pre-stressed condition.
2. Method of producing a pre-stressed frame construction comprising a pair of yokes separated by a plurality of intermediate pillars and a clamping means surrounding said yokes and pillars, said method including the steps of fitting said yokes and pillars loosely in said surrounding clamping means, applying equal forces in opposite directions to said yokes to stretch said clamping means and give it a stress at least equal to the desired final pre-stress, thereby providing clearance between said yokes and the end of said pillars, then inserting fillers to substantially fill each of said clearances, and removing said forces, said fillers thereby retaining the construction in extended pre-stressed condition.
References Cited by the Examiner UNITED STATES PATENTS 1,872,115 8/32 Byerlein 29452 XR 2,539,056 1/51 Brown 29-447 2,938,260 5/60 Holben et al. 29l56.4 3,115,696 12/63 Evans 29149.5
WHITMORE A. WILTZ, Primary Examiner.
THOMAS H. EAGER, Examiner.
Claims (1)
1. METHOD OF EFFECTING A DESIRED DEGREE OF PRE-STRESS IN A CONSTRUCTION COMPRISING A PLURALITY OF PILLARS SEPARATING A PAIR OF YOKES AT OPPOSITE ENDS OF A SURROUNDING STRIP CASING, SAID METHOD INCLUDING THE STEPS OF APPLYING EQUAL FORCES IN OPPOSITE DIRECTIONS TO SAID YOKES TO STRETCH SAID CASING AND GIVE IT A STRESS AT LEAST EQUAL TO THE DESIDERED PRE-STRESS, THEREBY PROVIDING CLEARANCES BETWEEN SAID YOKES AND THE END OF SAID PILLARS, THEN INSERTING FILLERS TO SUBSTANTIALLY FILL EACH OF SAID CLEARANCES AND REMOVING SAID FORCES, SAID FILLERS THEREBY RETAINING THE CONSTRUCTION IS EXTENDED PRE-STRESSED CONDITION.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE1308162 | 1962-12-05 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3210837A true US3210837A (en) | 1965-10-12 |
Family
ID=20296792
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US327236A Expired - Lifetime US3210837A (en) | 1962-12-05 | 1963-12-02 | Method of effecting pre-stress |
Country Status (2)
Country | Link |
---|---|
US (1) | US3210837A (en) |
GB (1) | GB1057859A (en) |
Cited By (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3581656A (en) * | 1969-06-11 | 1971-06-01 | Verson Allsteel Press Co | Prestressed press |
US3747393A (en) * | 1970-09-29 | 1973-07-24 | Schloemann Ag | Drop forging press |
US3884142A (en) * | 1973-01-19 | 1975-05-20 | Carbox Ab | Machine frame, having a biased wire girdle, and a method for biasing such a girdle |
US3992837A (en) * | 1974-07-29 | 1976-11-23 | Allmanna Svenska Elektriska Aktiebolaget | Press stand |
US4182018A (en) * | 1977-04-09 | 1980-01-08 | Siempelkamp Giesserei Gmbh & Co. | Method of and apparatus for the stressing of pressure vessels |
US4360143A (en) * | 1980-02-07 | 1982-11-23 | Dana Corporation | Method for manufacturing suspension members |
US4738388A (en) * | 1984-07-24 | 1988-04-19 | Steag Kernenergie Gmbh | Process for sealing a container for storing radioactive material and container for implementing the process |
ITRE20090052A1 (en) * | 2009-05-27 | 2010-11-28 | Sacmi | PRESS AND ASSEMBLY METHOD FOR A PRESS. |
CN108037015A (en) * | 2017-12-17 | 2018-05-15 | 四川航空工业川西机器有限责任公司 | A kind of large diameter ultra high pressure cylinder for deep sea pressure simulation test |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1872115A (en) * | 1932-08-16 | byerlein | ||
US2539056A (en) * | 1944-09-02 | 1951-01-23 | Chicago Pneumatic Tool Co | Method of assembling tool joints |
US2938260A (en) * | 1954-04-02 | 1960-05-31 | Curtiss Wright Corp | Method of fabricating cylinder barrels |
US3115696A (en) * | 1962-04-25 | 1963-12-31 | Tropel | Method of making mechanical slide |
-
1963
- 1963-12-02 US US327236A patent/US3210837A/en not_active Expired - Lifetime
- 1963-12-03 GB GB47618/63A patent/GB1057859A/en not_active Expired
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1872115A (en) * | 1932-08-16 | byerlein | ||
US2539056A (en) * | 1944-09-02 | 1951-01-23 | Chicago Pneumatic Tool Co | Method of assembling tool joints |
US2938260A (en) * | 1954-04-02 | 1960-05-31 | Curtiss Wright Corp | Method of fabricating cylinder barrels |
US3115696A (en) * | 1962-04-25 | 1963-12-31 | Tropel | Method of making mechanical slide |
Cited By (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3581656A (en) * | 1969-06-11 | 1971-06-01 | Verson Allsteel Press Co | Prestressed press |
US3747393A (en) * | 1970-09-29 | 1973-07-24 | Schloemann Ag | Drop forging press |
US3884142A (en) * | 1973-01-19 | 1975-05-20 | Carbox Ab | Machine frame, having a biased wire girdle, and a method for biasing such a girdle |
US3992837A (en) * | 1974-07-29 | 1976-11-23 | Allmanna Svenska Elektriska Aktiebolaget | Press stand |
US4182018A (en) * | 1977-04-09 | 1980-01-08 | Siempelkamp Giesserei Gmbh & Co. | Method of and apparatus for the stressing of pressure vessels |
US4360143A (en) * | 1980-02-07 | 1982-11-23 | Dana Corporation | Method for manufacturing suspension members |
US4738388A (en) * | 1984-07-24 | 1988-04-19 | Steag Kernenergie Gmbh | Process for sealing a container for storing radioactive material and container for implementing the process |
ITRE20090052A1 (en) * | 2009-05-27 | 2010-11-28 | Sacmi | PRESS AND ASSEMBLY METHOD FOR A PRESS. |
EP2255960A1 (en) * | 2009-05-27 | 2010-12-01 | SACMI Cooperativa Meccanici Imola Società Cooperativa | Press with a pre-stressed frame and method for mounting said press |
RU2555696C2 (en) * | 2009-05-27 | 2015-07-10 | Сакми Кооператива Мекканичи Имола Сосиета' Кооператива | Press and its assembly |
CN108037015A (en) * | 2017-12-17 | 2018-05-15 | 四川航空工业川西机器有限责任公司 | A kind of large diameter ultra high pressure cylinder for deep sea pressure simulation test |
Also Published As
Publication number | Publication date |
---|---|
GB1057859A (en) | 1967-02-08 |
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