US3267568A

US3267568A - Apparatus for hydraulically removing and replacing interference fitted parts and the like

Info

Publication number: US3267568A
Application number: US278958A
Authority: US
Inventors: Howard M Johnson; Jeffery D Irons
Original assignee: Orbit Valve Co
Current assignee: Orbit Valve Co
Priority date: 1963-05-08
Filing date: 1963-05-08
Publication date: 1966-08-23
Anticipated expiration: 1983-08-23

Description

3, 1966 H. M. JOHNSON ETAL 3, 6 ,568

APPARATUS FOR HYDRAULICALLY REMOVING AND REPLACING INTERFERENCE FITTED PARTS AND THE LIKE Filed May 8, 1963 4 Sheets-Sheet 1 INVENTORSI HOWARD M. JOHNSON JEFFERY D. IRONS ATTORNEYS g- 23, 1956 H. M. JOHNSON ETAL 3,267,568

R H LY REMOVI APPAR S ICAL NG AND PLACING TE RE TTED PARTS AND THE E Filed May 8, 1963 4 Sheets-Sheet 2 1N NTORS:

HOWARD JOHNSON JEFFERY D [R0 NS ATTORN EYS g- 1966 H M. JOHNSON ETAL 3 7, 68

APPARATUS FOR HYDRAULICALLY REMOVING AND REPLACING INTERFERENCE FITTED PARTS AND THE LIKE Filed May 8, 1963 4 Sheets-Sheet 5 2 220 226 222 228 214 as f INVENTORSI HOWARD M. JOHNSON JEFFERY D. IRONS BY M4Mm- ATTORNEYS Aug. 23, 1966 H M. JOHNSON ETAL 8 APPARATUS FOR HYDRAULICALLY REMOVING AND REPLACING INTERFERENCE FITTED PARTS AND THE LIKE INVENTORS: HOWARD M. JOHNSON JEFFERY D. IRONS BY IM ATTORNEYS 3,267,568 APPARATUS FGR HYDRAULIiJALLY REMQVWG AND REPLACING INTERFERENCE FITTED PARTS AND THE LIKE Howard M. Johnson, Lafayette, La, and Jeffery D. Irons, Tulsa, Okla, assignors to Orbit Valve (Iompany, Tuisa, 0kla., a corporation of Oklahoma Filed May 8, 1963, Ser. No. 278358 8 Claims. (Cl. 229-413) This invention relates to apparatus for separating interference fitted parts. More specifically, the invention relates to apparatus for hydraulically separating valve seats from valve bodies which have been fitted with a high degree of interference.

It is a Well known engineering design function to fit parts together with a high degree of interference such that in normal usage the parts will not move relative to one another. Typically such interference fit occurs by dimensionally designing the parts such that their fit comes about by a press or a shrink process. Parts that have been joined in this manner frequently represent the best possible design permissive of equalizing stresses from one part to the other. In many valves and pumps 21 high interference fit between a seat ring and the body performs the sealing function in a manner not possible by any other means except integrally welding or soldering the mating pieces together. It has also been known that a high degree of press fit produces a high contact pressure between the mating parts and in addition to the scaling function all fluid is excluded from between the parts. This has been known to prevent corrosion from occurring even when the mating parts are dissimilar metals.

Additionally, it has been known to be advantageous in the construction of certain rotating machinery as centrifugal and axial flow pumps and compressors to press fit the impellers on the shaft. Such a design imparts intrinsic, static and dynamic balance to the rotating assembly. One of the problems, however, has been the difiiculty in disassembly of the mating parts.

It is also Well known in the engineering arts that high interference fitted parts can usually be joined together with comparative ease, but such interference fitted parts are frequently omitted from engineering design because of the problems in separating the parts later. Typical of this problem is in the construction of valve seats in valve bodies. Typically, the seat is installed at the manufacturers plant using hydraulic presses and other available equipment. Ordinarily with such equipment the seat can be removed from the valve. The problem remains, however, in the removal of the seat at its inline looation after it has once left the factory. It has been found that in many instances in removing valve seats from valve bodies using mechanical pullers or means an uneven pulling force is applied to bind to the walve seat within its bore. Typically this results in injury to the bore necessitating a grinding operation and replacement with an oversized valve seat. In many instances such procedures are difiicult if not impossible at the field location of the valve.

Accordingly, it is a primary object of this invention to provide apparatus for overcoming the problems heretofore associated with interference fitted parts.

It is another object of this invention to provide an apparatus for separating interference fitted parts, hydraulically, and with equipment readily available and usable at the location of the equipment or parts and without removal of the equipment or interfering with its future operation.

It is a particular object of this invention to provide apparatus for hydraulically separating v alve seats from valve bodies using hydraulic equipment, which is readily availnited States Patent able and usable at the on-line location of the valve, and without removing the valve from its position.

A still further object of this invention is to provide apparatus which can be used internally of cylindrical mating parts for separating interference fitted parts by external application of hydraulic pressure.

A yet further object of this invention is to provide an apparatus capable of hydraulically separating interference fitted parts wherein there is equality and inequality of diameters with respect to the interference fitted parts.

Still another object of this invention is to provide an apparatus for hydraulically replacing parts in interference fitted relation.

These and other objects of this invention will become more apparent upon further reading of the specifications and claims when taken in conjunction with the following illustrations of which:

FIGURE 1 is a sectional view, partly in elevation, of the preferred apparatus for removing interference fitted valve seats from valve bodies hydraulically.

FIGURE 2 is a sectional view, partly in elevation, describing apparatus for hydraulically removing valve seats from valve bodies in those instances where the internal bores are of unequal diameter.

FIGURE 3 is a partial sectional view of an apparatus constructed in accordance withthis invention for removing a die bushing from a die set.

FIGURE 4 is a partial sectional view of an apparatus for hydraulically removing cylindrical interference fitted parts which have the same exterior diameter.

FIGURES 5 and 6 are partial sectional views of an apparatus for removing cylindrical interference fitted parts which are of unequal outside diameter.

FIGURES 7, 8, 9, 10, 11 and 12 represent additional modifications of this invention.

FIGURE 13 represents an additional embodiment of this invention for inserting valve seats within a valve body.

General description Broadly speaking, this invention is concerned with separating interference fitted parts by hydraulic pressure. The various apparatus herein create a confined (annular space across the interference fitted parts. A force equal to the product of the hydraulic pressure and the annular crosssectional area of the object which is to be displaced is applied to cause separation. In essence, the cylindrical body which is to be removed becomes an annular piston to overcome the friction of its interference fit with respect to the mating part which serves as a cylinder for the piston.

Detailed description Referring now to FIGURE 1, a valve seat puller 19 of this invention is shown positioned with respect to a valve seat 12 which is interference fitted within valve body 14 and which is to be removed therefrom using the puller. The puller is cylindrical in shape and includes an inner cylindrical portion 16 and outer cylindrical portion 18. The two axially spaced

grooves

20 and 22 are adapted .to receive O-

rings

24 and 26 and expansible rings 28 and 39, respectively, the latter of which are positioned exteriorly of the O-rings. The

rings

28 and 30 are adapted to aid in retaining the O-rings in a sealed position and prevent any extrusion or leakage during the application of hydraulic pressure. The axial spacing of the two grooves and O-ring systems is made such that one is adapted to seal effectively with respect to the removable seat 12, while the other is adapted to seal with respect to the valve body 14. A hydraulic pressure channel 32 extends between the space between the seal' O-ring system and the exterior of the valve puller 1t} terminating, in

one embodiment, with a valved grease connection 34, which in this instance is located along the peripheral edge of the larger diameter body portion 13. In other instances it may be desirable to remove the threaded plug 36 and adapt a connection at this point to the channel 32 instead of that shown, of course, plugging the other channel opening.

In operation of the embodiment of FIGURE 1, the puller is inserted into the interior bore of the valve body 14 and valve seat 12 as shown. Suitable hydraulic media such as grease, oil, or others is umped into channel 32 using an ordinary grease gun, hand pump, or power pump connected to element The hydraulic media forces its way through channel 32 into the space between the seals and the space between the back edge of valve seat 12 representing the cross-sectional area of the valve seat. The interference it of valve seat 12 with respect to the valve body lidserves as a pressure tight seal around the circumference of the valve seat and hence prevents escape of the hydraulic media. Since in this embodiment the internal bore within which the uller operates is of the same diameter, the forces upon the puller are balanced, permitting increasing pressure of the hydraulic media without any unbalancing forces on the puller. However, upon sufficient pressure build-up operating against the effective cross-sectional area of the valve seat 12, the valve seat will begin to move axially in its counter bore. At this point the product of the annular cross-sectional area of the valve seat and pressure is greater than the frictional interference fit holding force. As the valve seat moves it will also move the puller causing the seal as to slide with reference to the valve body 14. Continued displacement of the pressure media into the annular Zone will eventually separate the valve seat 12 from the valve body The axial spacing of the two

seal systems

24 and 26 is such that the former maintains its seal with respect to the valve seat 12 and the latter maintains its seal with respect to the valve body 14 until effective separation is accomplished. Although the hydraulic pressure media channel 323 is shown terminating in a connection 34, it is to be understood that such connection can be made on the right hand end of the valve puller, in that instance there is sutlicient room to effectively apply hydraulic pressure. however, this would entail disconnecting the line connection with the valve.

The embodiment of FIGURE 2 effectively employs the principles of this invention applied, however, to that situation in which the effective internal bore of valve seat 12 with respect to valve body 14 is not equal. Typically, this occurs where the valve body is of the threaded end variety to receive a complementary threaded tubing Accordingly, the apparatus of this embodiment is adapted to provide an inner-cylindrical assembly d2, one end of which is a larger diameter cylindrical portion 44. A groove as is adapted to receive O-ring seal 48 and an expansi'ble back-up ring St). A hydraulic pressure media channel 52 extends from the interior end of the smaller diameter cylindrical portion 42 to an exterior connector 54 for connection to a high pressure hydraulic power source, not shown. The O-ring 4-3 and back-up ring Eli are adapted to maintain a sealing engagement with the valve seat 12. Seal adjustment member 56 is threadably re ceived axially with respect to

cylindrical members

42 and 44 being sealed by suitable O-ring 58 with respect thereto. The seal adjustment member 56 extends exteriorly of the cylindrical portion id and includes means for attachment thereto to rotate the member, such as by using a ratchet connection, or the like. The other end of the seal adjustment member terminates with an inner-cylindrical body portion on which includes a multiplicity of elements for maintaining an effective seal between the body portion as and the internal diameter of the tubing 49. A fixed seal is ordinarily not possible, due to the considerable variance in internal pipe diameter. The elements for providing this effective seal include back-up element 6?.

which retains

frictional drag members

64 and 66 which further act as back-up for the resilient seal member es. The frictional drag members 6 and as cooperate with respect to an inclined plane 7% by which adjustable drag with respect to the interior bore of tubing ill is effected by the rotational movement of the seal adjustment member Member 56 is adjusted so as to provide sufiicient frictional drag to offset thehydraulic unbalance in the puller apparatus.

in operation the preassemblcd apparatus as shown in FEGURE 2 is inserted internally into the internal bore comprising the valve seat 12 and the tubing 49. An effective seal and frictional drag of elements 68, 61; and 54 is produced by rotating the seal adjustment member 56, which in turn rotates body oil with respect to backup member 62 effectively causing greater or less frictional engagement of

members

64 and 66 as it operates with respect to the inclined plane '70. Once an effective seal is accomplished, hydraulic pressure media, as heretofore described, is forced into that space between seals 48 and 68 to operate against the effective cross-sectional area of valve seat 12 and thus force relative separating movement of the valve seat with respect to the valve body 14- and tubing iii. Once separation has been accomplished, the seal adjustment member is reversely rotated causing a reduction in effective diameters of elements 64, as and as and hence permitting removal of the system from the valve body and pipe line.

The apparatus of FIGURE 3 shows an additional embodiment of this invention as adapted for removing a cylindrical bushing 72 from an interference fit with respect to a die set id, the latter of which is retained to a die holder 7s in sealed relationship using O-ring 78. In this instance, as shown, the efiective internal bore of the die holder and the bushing '72 are unequal In that instance a cylindrical puller 8d includes a sealed groove portion 82 having an O-ring 84 and split ring 86 therein as shown which is adapted for sealed engagement with the bushiru 72 and an axially spaced groove 38 adapted to re eive O-ring and split Teflon ring 92, which creates an effective hydraulic pressure space. In that instance the movement length of the bushing '72 with respect to the die set 74 is greater than the length of the O-ring 9i) will travel upon the respective die holder bore. An auxiliary sealing groove as having an O-rlng 96 and Teflon split ring 98 therein is provided for making a secondary effective seal to the die holder and the space between O-ring 84 for continued hydraulic pressure against bushing 72. A hydraulic pressure channel 109 extends from the space between the O-rings to an exterior connection such as zerk run for connection to a hydraulic power source as heretofore described.

In operation the puller 8t) is inserted into the internal bore of the bushing and die holder where effective seal is retainedbetween the two. Thereafter a retainer member fil is attached to the puller body 39 to permit contact of the bushing 72. thereagainst for axial movement as hydraulic pressure is applied.

FIGURE 4 represents an additional embodiment of this invention wherein it is desired to remove a cylindrical bushing Hill as for example from a cylindrical shaft 112. In this instance a cylindrical sleeve 114 is adapted with an interiorly directed flange portion 116 which abuts against the bushing lit). Spaced

grooves

118 and 120 are adapted with sealing assemblies consisting of O-rings 122 and 126, respectively, and split rings 124 and 123, respectively. Between the two seals hydraulic pressure fluid conduit 13% terminates with connection 132, for connection with a hydraulic fluid power source.

In operation hydraulic pressure fluid is forced into that space between the two O-ring seals 122 and 126 and is adapted to operate against the effective cross-sectional area bushing 11d forcing same outward. An effective seal is maintained between the parts by proper axial spacing of the two O-ring systems in order that an effective seal of ring 126 with respect to the shaft 112 is maintained until separation of the bushing occurs.

FIGURE 5 describes apparatus for removing bushing 134 from a shaft 136. In that instance the external diameters of the two parts are unequal. Puller 138 is a cylindrical sleeve having an inwardly extending flange portion 140 for abutting engagement with the bushing 134. Internally of the sleeve are two effective

diameter groove portions

142 and 144 having O-ring and Teflon seals 146 and 148, as heretofore described, therein which respectively engage the smaller diameter bushing 134 and the larger diameter shaft 136 creating a sealed space therebetween having a connecting conduit 150 and high pressure connection 152. In this instance there is a hydraulic unbalance of the uller assembly which is overcome by adding a frictional force to the system. This latter is tacomplished by partially cylindrical arcuate wedge block 154 which is adapted to be pressed into tighter frictional engagement with the shaft 136 by advancing a cooperating wedge block member 156 toward the rear- Ward end of the puller 138 by threaded adjustment of bolt 158. In this instance the net pulling force available to force bushing 134 away from its shaft 136 is a product of the hydraulic media pressure and the net seal area less the frictional component on the puller as adjusted.

Referring now to FIGURE 6, apparatus is described for removing a cylindrical bushing 160 interference fitted with respect to shaft 162, and wherein the external diameter of the bushing is greater than that of the shaft. In this instance a pulling sleeve 164 is adapted to fit over the respective parts and includes a groove 166 having sealing elements 168 and groove 170 having sealing elements 172 therein. The former sealing elements are adapted to the peripheral sunface of bushing 160, while the latter abut the peripheral diameter of shaft 162, creating a space for the injection of hydraulic pressure media through passageway 174 and pressure source connection 176. A multiplicity of transverse extension flanges 178 are adapted to be locked to sleeve 164 whereby bushing 160 is adapted to contact the flanges as a part of the overall operation of the invention.

In operation hydraulic pressure fluid is forced through connection 176 and passageway 174 into the space between the sealing

elements

168 and 172. The net pulling force is sufficient to cause bushing 160 to contact flange elements 178, forcing the sleeve to move axially along the shaft until separation of the interference fit is accomplished. The net pulling force is equal to the product of the pressure of the hydraulic media pressure and the net seal area exposed to the hydraulic media.

FIGURE 7 shows a two piece puller arrangement for use in a situation as previously described with reference to FIGURE 2; that is, where the effective internal bore of the valve seat 180 is not equal to the effective internal bore of tubing 182 threadably attached to the body 183 of the valve. The tubing sealing structure 184 is substantially the same as the inner-cylindrical body portion 60 of FIGURE 2 with the exception that seal adjustment member 56 of FIGURE 2 has been removed and replaced by a threaded plug member 186. Plug 186 is provided on its inner end with a radially extending flange portion 188 that contacts the inner end 190 of tubing 182. Likewise, the inner-cylindrical assembly 192 is of the same construction as the inner-cylindrical assembly 42 of FIG- URE 2 with the exception that seal adjustment member 56 of FIGURE 2 is replaced by a pawl actuating arm 194. In operation, the tubing sealing structure 184 is positioned within the end of the tubing and sealing thereof effected in the manner above described. Arm 194 is then placed inwardly of cylindrical portion 192 sufficiently to allow the pawls 196 to be manually depressed radially inwardly. Cylindrical portion 192 is then inserted within valve seat 180. Arm 194 is then pulled outwardly -whereupon the cam surfaces 198 provided near the inner end of the arm urge pawls 196 radially outwardly into engagement with the inner surfaces 200 of valve seat 180. A pressurized medium is then forced through channel 202 into the space 204 isolated by the

seals

206, 208 and 184 to effect the pulling or removal of valve seat 180. During the pulling operation, flange 188 prevents tubing sealing structure 184 from being displaced into the tubing. Pawls 196 prevent the cylindrical portion 192 from being displaced from the bore of valve seat 180.

Although there does exist a hydraulic unbalance across this pulling assembly, since the assembly is divided into two parts and means are provided for preventing displacement of these parts, no frictional drag mechanism is required in thi apparatus.

FIGURE 8 discloses yet another alternate embodiment of this invention for the pulling or removal of a valve seat when the effective internal bore of the valve seat is greater than the internal bore of the threaded tubing attached to the valve, similar to the situation reflected in FIGURE 2.

Sleeve 210 having an outwardly extending flange portion 211 is provided on the end opposite flange 211 with annular sealing elements 212 for sealing engagement with the internal bore of valve seat 213. Extending through the central bore 214 of sleeve 210 is a shaft 215, one end of which extend into tubing 216 with the other end remaining inside the body of the valve. Sealing element 217 sealingly contacts the internal bore of tubing 216. Annular sealing element 218, provided near the middle portion of shaft 215, provides an annular seal between shaft 215 and the internal bore 214 of sleeve 210. Located internally of one end of shaft 215 is a chamber 219 which is in communication with the chamber 220 isolated by the sealing

elements

212 and 217 of this puller assembly. Slidably extending into chamber 219 is an elongated piston 222 provided with one or more annular sealing rings 224. The external end 226 of piston 222 contacts the head of an adjusting screw 228 that is in turn threadably connected to a retainer member 230 that contacts the valve body at a point opposite the location of the valve seat. The cross-section of chamber 219 is carefully chosen to equal the dilference in the sectional areas of the two annular sea-ls .212 and 217. Therefore, any hydraulic unbalance in the puller assembly is transmitted through piston 222, screw 228 and retainer member 230 to the valve body. In operation, as hydraulic fluid is pumped into chamber 220 through passage 231 the puller assembly and the valve seat will be moved inwardly of the valve body until the valve seat is removed from interference fit with the body.

Referring now to FIGURE 9, there is shown still another alternate embodiment of thi invention for use in removing a valve seat in a situation such as shown in FIGURE 2. In this embodiment a mechanical means is provided for offsetting the hydraulic unbalance in the puller assembly. The puller assembly including cylindrical portion 42A, seal adjustment member 56A and the tubing sealing structure composed of innercylindrical body portion 60A provided with element 62A, drag members 64A and 66A, and seal member 68A are the same as the corresponding parts shown in FIGURE 2. The head portion of an adjustable screw 232 contacts the inner end 234 of the seal adjustment member 56A. Screw 232 is threadably received within a retainer member 236 that abuts against and is received within the tubular opening in the valve body, opposite the valve seat 12A. Therefore, the hydraulic unbalance of this pulling apparatus is transmitted through screw 232 and retainer member 236 to the body of the valve. After hydraulic fluid is pumped into chamber 240 in a manner described in reference to FIGURE 2, screw 232 is backed otfin small increments to allow movement of the entire puller assembly and valve seat inwardly of the valve body until the valve seat is removed. Since asavgaea the hydraulic unbalance of this puller assembly is transmitted to the body of the valve, the frictional drag elements of the assembly may be omitted or may be included simply to assist in effecting a seal against the internal bore of the tubing l-iiA.

Referring now to FIGURE 10, there is shown an alternate embodiment of this invention for use in unseating a valve seat in a situation similar to that reflected in FIGURE 2. The tubing sealing structure 238 is the same as that described with reference to FIGURES 2 and 9. The pulling apparatus of this embodiment is intended to remain stationary while the valve seat is removed from position in the valve body. Inner-cylindrical portion 24% is substantially elongated axially and is provided with several annular sealing elements 242 near one end for sealing engagement with the internal bore of the valve seat 243. A seal adjustment member 246 sealably extends through a central bore 248 in cylindrical member 240 and is threadably attached to the tubing sealing structure 238. The head portion of an adjuster screw 25% contacts the inner end of seal adjustment member 246 with the threaded portion of screw 256? being received within a frustro-conical shaped retainer member 252. Member 252 extends at least part way within the passage 254 through the valve body, opposite the passage including the valve seat 243. Therefore, hydraulic unbalance of this pulling apparatus or assembly is transmitted through screw 25%) and retainer member 252 to the body of the valve to prevent any lateral movement of the assembly relative to the valve.

When hydraulic fluid is pumped through passage 256 into the chamber 25? isolated by the two

parts

238 and 240 of this pulling assembly, the valve seat 243 will be moved axially along the length of inner-cylindrical portion 240 and out of seating engagement with the body of the valve. It should be understood that in order for this apparatus to be operable there must be a suflicient number of sealing elements 242 spaced over a sufficient length of inner-cylindrical portion 249 to insure a seal between portion 240 and the valve seat 243 until the valve seat is completely removed from interference fit with the valve body.

Referring now to FIGURE 11, there is shown a modifled stationary pulling apparatus for use in pulling or removing valve seat from a valve in a situation as indicated with reference to FIGURE 10. The apparatus disclosed in FIGURE 11 is intended to remain stationary during the pulling or removing operation with the valve seat moving axially along the length of the pulling apparatus. valve seat 260 into contact with the end 261 of tubing 2.62. Shaft 258 is provided with an annular sealing element 264 for sealing engagement with the end 261 of the tubing 262. Shaft 258 is also provided with a plurality of annular sealing elements 266 that sealably contact the internal bore of valve seat 26%. Adjustable screw 268 and retainer member 27h are provided in contact with one end of shaft 258 for transmitting the hydraulic unbalance in this puller apparatus from the apparatus to the body of the valve, thereby to hold the apparatus stationary during the pulling operation. When hydraulic fluid is pumped through passage 272 into the chamber isolated by the sealing elements 266 and 26d of this pulling apparatus, the valve seat 261? will be actuated axially along the length of shaft 253 until it is completely unseated from position in the valve body.

The pulling apparatus as shown in FIGURE 12 is constructed similarly to and operates in the same manner as the pulling apparatus disclosed in FIGURE 11 and discussed above with the exception of the method for effecting the seal between the shaft 258A and the valve body. As can be seen in the'figure, annular sealing element 273 is of the O-ring type and is designed to sealably contact the valve bore 27 immediately behind the valve seat 276.

Inner-cylindrical shaft 258 extends into the it should be noted that the embodiments disclosed in FIGURES 11 and 12 include on the tubing end of the puller shaft 253 and 258A, respectively, a plugged hydraulic fluid opening 275% and 289, respectively, which allows operation of the pulling apparatus from the tubing side of the valve.

Referring now to FEGURE 13, there is shown an interference fit valve seat inserter that utilizes the same general theory of operation as the valve seat pullers above described. The inserter consists of a hydraulic cylinder 23?; having reciprocably disposed therein an elongated hydraulic piston 28 i. Piston 284 is provided with at least one annular O-ring type sealing element 286 for sealing contact with the bore of cylinder 282. Valve seat holder 288 is removably received upon the external end of piston 234. Holder 28% is provided with a reduced diameter portion 2% about which the valve seat 292 is positioned.

In operation piston 234 is retracted into cylinder 282. Valve seat holder 288 is then positioned on the external end 289 of piston 284 and valve seat 292 is slipped about reduced diameter portion 2% of the holder. The thusly assembled apparatus is then positioned Within the valve body with the valve seat 29 2 positioned adjacent to the opening in the valve body designed to receive it. The closure plate 2% of cylinder 282 is provided with an annular shoulder 2% t at contacts the valve body opposite the valve seat. Hydraulic fluid is then introduced into the cylinder through passage 2%, thereby forcing the piston 284 outwardly. Continued outward movement of piston 12% will press valve seat 292 into interference fit with the body of the valve. The hydraulic pressure in the cylinder is then relieved to allow the piston 284 and valve seat holder 238 to be retracted after which the apparatus is removed from the valve body.

This invention provides a method of and apparatus for installing pressed-in valve seats and the like and removing same from equipment installed in a place remote from the elaborate and complete facilities of a factory. That is, this apparatus permits the use of shrink fitted, press fitted, and interference fitted parts in field repairable equipment.

The apparatus of this invention is easily operable by one man and does not require complete disassembly of the valve or similar equipment in which it is used.

Also, when removing valve seats and the like from equipment using the apparatus of this invention, there is no galling of the equipment in which or upon which the valve seat or similar element is located.

The invention has been described by reference to specific and preferred embodiments. It will be apparent, however, that many modifications can be made without departing from the spirit and scope of the invention. Accordingly, this invention should be construed not to be limited to the embodiments herein described but should be limited only by the scope of the appended claims.

What is claimed is:

l. Apparatus for hydraulically removing a cylindrical shaped element from interference fit with a mating structure comprising:

a substantially cylindrical body portion having a crosssectional configuration to permit said body portion to telescope with respect to said element and mating structure;

at least one annular sealing means on said body portion for sealably contacting the annular surface of said element adjacent to said body;

at least one annular sealing means on said body for sealably contacting said mating structure thereby forming an annular hydraulic chamber between said sealing means;

passage means through said body to said chamber for the passage of hydraulic fluid to force said element from lit with said structure;

at least one radially adjustable frictional drag element attached to said body portion for frictional engagement with said mating structure to provide a frictional force to offset any hydraulic unbalance in said apparatus.

said mating structure at a point opposite said element to said first body structure to offset any hydraulic unbalance in said apparatus.

4. Apparatus of claim 3 wherein said first body strucshaped element from interference fit within the bore of a mating structure comprising:

a first substantially cylindrical body portion for limited insertion into the bore of said mating structure to a 2. Apparatus for hydraulically removing a cylindrical 5 point distant from said element in a direction opshaped element from interference fit with a mating strucposite the direction of removal of said element; ture comprising: an annular sealing means on said first body portion for a substantially cylindrical shaped body portion having a sealably contacting the bore of said mating structure;

cross-sectional configuration to permit said body pora second substantially cylindrical body portion for intion to telescope with respect to said element and sertion into the bore of said element; mating structure; an annular sealing means on said second body portion at least one annular sealing means on said body porfor sealably contacting said bore of said element tion for sealably contacting the annular surface of thereby forming a sealed hydraulic chamber between said element adjacent to said body; said first and second body portions;

at least one annular sealing means on said body porat least one retainer means provided on said second tion for sealably contacting said mating structure body portion radially movable from a closed position thereby forming annular hydraulic Chamber flush with the annular surface of said second body tween said sealing means; portion to an open position of contact with said elepassage means through said body portion to said chamment on the side opposite the direction of removal of ber for the passage of hydraulic fluid to force said said element; element from fit With Said Structure; an operator mandrel extending coaxially through said means extending radially from said body portion for e ond body ortion movable axially from a first contact with said element as said element is forced position to a second position to open said retainer from fit with said structure whereby said body is means; moved by and in the same direction as said element; a passage means through said second body portion to a cylindrical Passage extending COaXiauY into one 611d said chamber for the passage of hydraulic fluid to of Said y POYtiOll; force said element from fit with said structure.

a lateral, Small diameter, Passage Connecting interior 6. Apparatus for hydraulically removing a cylindrical extremity of Said Cylindrical Passage With Said yshaped valve seat from interference fit with a valve body dl'aulic chamber; comprising in combination therewith:

a Piston fecipfocably received Within Said Cylindrical a cylindrical portion having a cross-sectional configura- P tion to permit said portion to telescope within said a mechanical linkage contacting at itS one end the Valve seat and valve body one end of termieXtelnal end of Said Piston and at its other end with nates outwardly in a larger diameter portion abuttable said mating structure at a point opposite said elei t id valve seat; ment l as Said element is forced fit With a first annular sealing means on said body portion con- Said mating Structure, Said Piston moves lllwardly tacting against the annular surface of said valve seat of said cylindrical passage to apply a hydraulic force adjacent to Said bedy;

Sufiicient to Oflset any hydraulic unbalance in Said a second annular sealing means onsaid body contacting apPafatusagainst said valve body to form an annular hydraulic 3. Apparatus for hydraulically removing a cylindrical h b b t ee aid sealing means;

shaped element from interference fit with a mating struceach f Said Sealing means Comprising a groove d tum Comprising: spectively outward from said hydraulic chamber a a first substantially cylindrical shaped body structure resilient Gring and an expansible ring; and

having a cross-sectional configuration to permit said Passage means through Said body to Said chamber for first body structure to telescope with respect to said the passage of hydraulic fluid to force Said valve Seat element; i from fit with said valve body whereby said valve seat a second substantially cylindrical shaped body structure contacts said larger diameter portion causing Said having a cross-sectional configuration to permit said Valve seat and said apparatus to move in the Same second body structure to telescope with respect to direction sa1d matmg stmciure; 7. Apparatus for hydraulically removing a cylindrical means for cqnnectmg sa1d first and Said Second body shaped insert from interference fit with a mating structure structures in coaxial end-to-end spaced apart relacomprising: non; a first substantially cylindrical shaped body structure least one annular Sealing f sa1d first body having a cross-sectional configuration to permit said struciuw for sealtbly contacimg t annular Surface first body structure to telescope with respect to said of sa1d element ad acent to sa1d body, insert;

at least one annular seahng mealis on t secfmd body a second substantially cylindrical shaped body structure structure for sealably contacting sa1d mating struch l nfi t ture thereby forming an annular hydraulic chamber avmg a Cross sec Iona co gum Ion Penm Sal b o0 second body structure to telescope with respect to etween sa1d sealmg means, sa1d mating structure,

passage means through said body to sa1d chamber for f fir t d d b d the passage of hydraulic fluid to force said element means or cc-mnec Sal S an Sal scon y fmm fit With Said structure structures in coaxial end-to-end spaced apart relation;

a variable length mechaniczil linka e extending from at least one annular Sealing means on sa1d first body b 5 structure for sealably contacting the annular surface of said insert adjacent to said body;

at least one annular sealing means on said second body structure for sealably contacting said mating structure thereby forming an annular hydraulic chamber ture is provided with at least one radial extension for contact with said element as said element is forced from fit with said mating structure and said linkage is progressively shortened to allow said body and said element to move relative to said mating structure.

5. Apparatus for hydraulically removing a cylindrical between said sealing means;

passage means through said body to said chamber for the passage of hydraulic fluid to force said insert from fit with said structure; and

means for opposing and offsetting any hydraulic unbalance in said apparatus including at least one radially asst pee it adjustable frictionable drag insert attached to said second body structure for frictional engagement with said mating structure.

8. Apparatus for hydraulically removing a cylindrical shaped insert from interference fit With a mating structure comprising: 7

a first substantially cylindrical shaped body structure having a cross-sectional configuration to permit said first body structure to telescope With respect to said insert;

a second substantially cylindrical shaped body structure having a cross-sectional configuration to permit said second body structure to telescope With respect to said mating structure;

means for connecting said first and said second body structures in coaxial end-to-end spaced apart relation;

at least one annular sealing means on said first body structure for sealably contacting the annular surface of said insert adjacent to said body;

at least one radially adjustable annularsealing means on said second body structure for sealably contacting said mating structure thereby forming an annular hydraulic chamber between said sealing means;

means included in said apparatus for opposing and oilsetting any hydraulic unbalance in said apparatus.

References (fited by the Examiner UNITED FOREEGN PATENTS Germany.

W ELLIAM FELDMAN, Primary Examiner.

J. C. PETERS, Assistant Examiner.

Claims

6. APPARATUS FOR HYDRAULICALLY REMOVING A CYLINDRICAL SHAPED VALVE SEAT FROM INTERFERENCE FIT WITH A VALVE BODY COMPRISING IN COMBINATION THEREWITH: A CYLINDRICAL PORTION HAVING A CROSS-SECTIONAL CONFIGURATION TO PERMIT SAID PORTION TO TELESCOPE WITHIN SAID VALVE SEAT AND VALVE BODY, ONE END OF WHICH TERMINATES OUTWARDLY IN A LARGER DIAMETER PORTION ABUTTABLE AGAINST SAID VALVE SEAT; A FIRST ANNULAR SEALING MEANS ON SAID BODY PORTION CONTACTING AGAINST THE ANNULAR SURFACE OF SAID VALVE SEAT ADJACENT TO SAID BODY; A SECOND ANNULAR SEALING MEANS ON SAID BODY CONTACTING AGAINST SAID VALVE BODY TO FORM AN ANNULAR HYDRAULIC CHAMBER BETWEEN SAID SEALING MEANS;