US3604089A

US3604089A - Methods of manufacturing hollow bodies with separate elements enclosed therein

Info

Publication number: US3604089A
Authority: US
Inventors: Frans Harry Karlsson
Original assignee: Hykon Patent AB
Current assignee: Hykon Patent AB
Priority date: 1968-04-10
Filing date: 1969-04-01
Publication date: 1971-09-14
Anticipated expiration: 1988-09-14
Also published as: DE1916347A1; SE325377B; GB1267382A; FR2006008A1; BE731300A; NL6905497A; CH489302A

Abstract

In a method of manufacturing in one piece a hollow body which is to accommodate in a hollow space thereof one or more separate elements which cannot possibly, or only with difficulty, be mounted in the body without division thereof, the separate elements are enclosed in a core and the body is then shaped in one piece on the core by casting or otherwise, whereupon the core is removed so that the separate means are uncovered in the hollow space in the body.

Description

United States Patent Inventor Frans Harry Karlsson Lund, Sweden Appl. No. 812,160

Filed Apr. 1, 1969 Patented Sept. 14, 1971 Assignee Hykon-Patent Aktiebolag Lund, Sweden Priority Apr. 10, 1968 Sweden 4825/68 METHODS OF MANUFACTURING HOLLOW BODIES WITH SEPARATE ELEMENTS ENCLOSED THEREIN 6 Claims, 4 Drawing Flgs.

U.S. Cl 29/157,], 137/454.6, 251/148 Int. Cl. ..B2ld 53/00, B21k 29/00, 823p 15/26 Field of Search 29/157. 1;

[56] References Cited UNITED STATES PATENTS 3,049,794 8/1962 Bredtschneider 29/l57.1 3,081,792 3/1963 Hansen 29/157.l 3,100,501 8/1963 Hansen... 137/4546 3,182,952 5/1965 Montesi.. 251/148 3,192,948 7/1965 Anderson... 29/l57.l 3,271,845 9/1966 Breher.... 29/157.l

Primary Examiner-John F. Campbell Assistant Examiner-Donald P. Rooney Attorney-Beveridge & DeGrandi ABSTRACT: In a method of manufacturing in one piece a hollow body which is to accommodate in a hollow space thereof one or more separate elements which cannot possibly, or only with difficulty, be mounted in the body without division thereof, the separate elements are enclosed in a core and the body is then shaped in one piece on the core by casting or otherwise, whereupon the core is removed so that the separate means are uncovered in the hollow space in the body.

PATENTED SEPI4I97| 3504.089

SHEET 1 0F 4 INVENTOR. FRANS HARRY KARLsSQN by 61cm 514. 4% aww y,

I WW4 METHODS OF MANUFACTURING HOLLOW BODIES WI'II-ISEPARATE ELEMENTS ENCLOSED THEREIN This invention relates to a method of manufacturing in one piece a hollow body which is to accommodate in a hollow space thereof one or more separate elements which cannot possibly, or only with difficulty, be mounted in the body without division thereof.

l-Iollow bodies which are to contain separate elements must often be made divisible to permit mounting the separate elements in the hollow space of the body.

As examples of such bodies there may be mentioned valve housings which are to contain valve members. For instance, the valve housings of shutoff valves are usually cast in two parts, one part constituting the body of the housing and the other part a cover which is connected to a flange of the body with the aid of bolts. The cover is usually cast with a box for a packing for the valve rod and besides has to be sealed relative to the flange of the body of the valve housing by means of a cover gasket. The disadvantage connected with this embodiment is that the seal between the cover and the remaining portion of the valve housing will often become deficient after some time of use and has to be replaced, which may prove very difficult and costly at certain installations. Also, it is basically more expensive to manufacture a valve housing in two parts with relatively good fitting between the parts than to manufacture the housing in one piece, if this were possible. Moreover, the two-part embodiment described requires boring a number of holes in the cover and the flange of the valve housing, mounting the valve member in the housing and assembling the valve housing details. Some of these operations might be dispensed with if it were possible to manufacture the valve housing in a single piece.-

This has now been made possible by the present invention, which relates to the manufacture of a valve comprising a cast valve housing having inlet and outlet ports and a movable valve member situated in said housing and operable via an operating means which extends through an opening in the valve housing. Characteristic of the method according to the invention is that the valve member is manufactured and enclosed in a core and that the valve housing is cast in one piece on the core whereby the valve member is enclosed in the housing, that the core is then removed through one of the ports of the valve housing for releasing the valve member therein, and that the valve member is connected to the operating means which is introduced for this purpose preferably from outside through an opening provided therefor in the valve housing.

Molding of the hollow body on the core can be performed by conventional casting methods and molding of the core can be performed according to conventional core molding methods, for instance the shell molding method.

The method of the invention is particularly suited for easting valve housings of metal in one piece around a metallic valve member enclosed in the core, said metallic valve member being preferably shaped and, as the case may be, finished for immediate use to avoid inconvenient final working thereof in the interior of the valve housing.

The method of the invention is applicable to the manufacture of sluice valves and other shutoff valves where special advantages are gained.

The invention will now be more fully described in the following by way of example when applied to the manufacture of a low pressure type shutoff valve, reference being made to the accompanying drawings in which:

FIG. I is an axial sectional view of a sluice valve;

FIG. 2 is a similar view showing the valve in FIG. 1 after casting of the valve housing but before removal of the core;

FIG. 3 is a cross-sectional view of the valve housing shown in FIG. 2 taken at right angles to the axis of flow and showing the valve housing after removal of the core but before mounting of the valve rod and positioning of the sealing rings;

FIG. 4 is an axial sectional view of a shutoff valve having a conical valve member.

The valve shown in FIG. I is a sluice valve of the conventional type except for the simplifications gained by the invention in casting the valve housing in one piece. The valve housing comprises a lower body having an inlet and an outlet connecting socket 2, 3, and an upper body 4 cast integrally with the lower body and accommodating the slide-type valve member 5 in the open position thereof. At the mouth of each socket 2, 3 leading into the bore of the valve housing there is formed a seat which is an annular groove with a sealing ring 6 and 7, respectively, therein. The valve member or slide 5 substantially is in the form of a disk having an annular sealing surface on each side for application against the sealing rings 6 and 7. These sealing surfaces on the slide are formed by the edge surface of annular flanges 8 and 9, said edge surface lying in two planes converging towards the interior of the slide or the lower end thereof, as viewed in FIG. 1. The annular grooves for the sealing rings 6 and 7 are formed with conforming convergence and therefore the sealing rings are placed at a suitable inclination in the valve housing for receiving the wedge-shaped disk-type slide which is operable in conventional manner by means of a spindle 10 whose outer end portion projects outwardly through an opening at the top of the upper body 4 of the valve housing 1 and carries a handwheel 11 at said end portion.

Provided on the part of the spindle 10 extending through the opening therefor in the upper body 4 of the valve housing 1 are three annular grooves two of which accommodate an O- ring-

type gasket

12 and 13, respectively, while the third innermost groove accommodates a washer 14 which engages the bottom surface of an annular groove on the inner side of the valve housing around the opening for the spindle 10. The latter is axially fixed in the valve housing with the aid of the washer l4 and the hub 15 of the handwheel 11, said hub engaging a flat surface or a washer 16 at the top of the upper body 4 of the valve housing and being held by means of a nut 17. By rotation of the handwheel 11 the slide 5 can be moved up and down in conventional manner in the valve housing since the axially fixed but rotatable spindle I0 is threaded and screwed into a threaded bore in theslide 5. At the bottom the valve housing has a threaded drain closed by means of a screw plug I8 which can be opened from outside, and the sockets 2, 3 are provided with bolt holes 19 for connection with the pipes of a pipeline.

The manufacture of the valve in FIG. I is illustrated in FIGS. 2 and 3. First, the slide 5 and the sealing rings 6 and 7 are manufactured from metal, such as brass or bronze cast in ingot molds or red brass cast in sand, and the said details are worked into a condition ready for use. The slide is then mounted on a supporting rod 21 which is inserted in the hole in the slide for the valve rod and is centered in the slide with the aid of washers 22. The sealing rings 6 and 7 are detachably secured to the slide in the position in which they are shown in FIG. 2, that is, the sealing rings 6 and 7 are mounted on the sealing surfaces of the annular slide flanges 8, 9 and connected to the slide in a suitable manner, for instance by adhesive or other suitable detachable bond. This being made, the unit comprising the slide 5, the sealing rings 6 and 7, and the rod 21 is enclosed in the core 23 so that the slide and the sealing rings are surrounded by that part 24 of the core which is to shape the hollow space in the upper body 4 of the valve housing. This part 24 of the core is connected or formed integrally with the remaining part of the core which is to shape the hollow space in the lower body of the valve housing 1, i.e. including the hollow spaces for the sockets 2 and 3,

projections

25 and 26 being formed on the core 23 around the supporting rod 21 for shaping the spindle opening 27 at the top of the upper body 4 of the valve housing, and the drain 28 at the bottom of the lower body of the valve housing.

The core 23 is given a suitable outer contour to facilitate forming the grooves 30 and 31 for the sealing rings 6 and 7. These grooves are machined after the casting of the valve housing to be smooth and to fit the sealing rings 6 and 7. Also the core 23 is given suitable tolerances to permit subsequent machining of the opening 27 for the spindle l0 and cutting internal threads in the drain 28 for the screw plug 18 closing said drain.

The core is preferably provided with a pair of parallel and substantially diametrical grooves extending in the longitudinal direction of the slide to shape a pair of guide ribs 32 on the inner side of the valve housing, and the slide is formed with a pair of guide studs 33 (see FIG. 3) for engaging said guide ribs. It may be suitable to shape said ribs in such a way that they are mutually offset to opposite sides of diametrical planes extending in the direction of motion of the slide in the valve housing, in which case the slide at the casting operation must be placed in the core in an angular position deviating from the normal operating position so that the guide studs 33 lie laterally of the grooves in the core and can be moved to positions opposite the guide ribs 32 (see left-hand part of FIG. 3) after casting. The core must then be so dimensioned as to allow said position of the slide and moreover the core must be so dimensioned that the sealing rings 6 and 7 can be moved downwards from the position shown in FIG. 2 past the inwardly directed

flanges

34 and 35 at the ends of which the grooves 30 and 31 for the sealing rings 6 and 7 are to be provided, as indicated in FIG. 2. These

flanges

34 and 35 are shaped in such a way that their end surfaces will take an inclination corresponding to that of the end surfaces of the slide flanges 8 and 9.

The right-hand part of FIG. 3 shows a possible modification of the guide for the slide 5. In this modification the guide ribs 32' are made slightly shorter so as to terminate a short distance beneath the top of the hollow space in the valve housing, and the studs 33' of the slide are made slightly longer and are formed with grooves for accommodating the guide ribs, the slide being enclosed in the core in such a position as to be located during casting a slight distance above its normal, fully open position, i.e. in such a way that the studs 33 go free from the upper ends of the guide ribs 32. After casting the slide is lowered somewhat to permit insertion of the ends of the guide ribs 32 in the grooves provided in the studs 33', whereupon the slide is fixed on the spindle so that it cannot any more be pulled up to a position in which the studs 33' are disengaged from the guide ribs. By this arrangement the slide will be guided and securely retained against rotation in opposite directions, which will spare the sealing rings 6 and 7 and prevents jamming of the slide.

Having been given its final shape the core is fixed in conventional manner in a mold for casting the valve housing 1, for instance in cast iron, which is customary. After casting, the core is removed and the annular grooves 30 and 31 are provided in the

flanges

34 and 35 by machining with the aid of tools introduced through the ports of the sockets 2 and 3. If necessary, the supporting rod 21 is first removed, but the slide 5 and the spindle 10 are retained in the upper body 4 of the valve housing in the positions shown in FIG. 2. Machining can be effected with the upper body of the valve housing turned downwards. After the provision of the grooves 30 and 31 the sealing rings 6 and 7 are released and moved down into the lower body of the valve housing, whereupon they are positioned in the grooves 30 and 31 in a suitable manner, for instance by hammering.

After machining of the hole 27 at the top of the upper body 4 of the valve housing, through which hole the spindle 10 is to extend, and after cutting internal threads in the drain 28 which is to be closed by means of the plug 18, the spindle 10 is mounted in the slide 5, the washer 14 being first introduced through one of the sockets 2 and 3 and passed onto the spindle. For this purpose, the washer 14 is divided and the parts thereof are yieldingly kept together by a spring clip 36 of bronze or other suitable material which permits sufficient spreading of the halves of the washer for passing the latter onto the spindle, and which then compresses the washer halves in the groove provided for said washer in the spindle 10, after the washer has been moved up to said groove by rotation of the spindle in the slide. The spindle can then be raised so that the washer is moved into the groove 37 provided for said washer in the valve housing, whereupon the handwheel 11 is secured in position so that the spindle is axially fixed in the valve housing.

The necessary treatment for finishing the valve housing on the outer side thereof are performed by some conventional method.

It has been assumed in the foregoing that the slide is in an integral piece and thus consists throughout of the same material. For economical reasons, however, it may be desirable to cast the slide from cast iron and to provide it with sealing rings of another metal secured by dovetailed grooves or in any other manner. It is also conceivable to substitute for the metal sealing rings 6 and 7 in the valve housing, valve seats which are machined on the valve housing flanges 34 and 35 (see FIG. 2) instead of the grooves 30 and 31.

It is also conceivable to place the metal rings 6 and 7 in another position in the core than that shown in FIG. 2. For instance, they can e disposed closely beneath the slide 5 or some distance beneath it, if the sludge well at the bottom of the valve housing is made sufficiently broad and deep for the purpose. If desired, the supporting rod 21 can be made slenderer to permit close relative location of the metal rings 6 and 7 beneath the slide 5, and it is also possible to substitute the metal rings for part of the rod 21 if said rings are placed in application against one another beneath the slide and are enclosed in said position in the core.

FIG. 4 shows an example of a shutoff valve having a conical valve member 50 which is operable in the valve housing 1 by means of a handwheel 11' and a spindle 10'. The conical valve member 50 cannot be introduced into the valve housing if the latter is not made divisible or the connecting sockets 2 and 3 are not made unreasonably large, but no difficulty is associated with the incorporation of the valve member 15 in question with a core and the casting of the valve housing in one piece, with the valve member positioned in the valve housing.

What I claim and desire to secure by Letters Patent is: 1. A method of manufacturing a valve having a unitary, integrally formed housing comprised of first and second portions with inlet and outlet ports and valve seats located in said second portion, and a valve member movable by an operating means extending through an opening in said housing between a position in said first portion of said housing in which said valve is opened and a position adjacent said valve seats in said second portion of said housing in which said valve is closed, comprising the steps of:

manufacturing and completely finishing said valve member, enclosing said valve member in a first portion of a unitary, integrally formed core in the position corresponding to said open position of said valve, said core having a second portion which is shaped so that it includes said inlet and outlet ports and so that it may be provided with said valve seats,

fixing said core in a mould for casting,

casting said valve housing around said core so as to form said first and second portions of said housing around said corresponding first and second portions of said core,

removing said core from said housing through either said inlet or outlet port, and

attaching said operating means to said valve member.

2. A method according to claim 1 further comprising the step of mounting said valve member on a supporting rod before it is enclosed by said core, said supporting rod being replaced by said operating means after casting.

3. A method according to claim 1 further including the steps of;

attaching manufactured sealing rings to said valve member before said valve member is enclosed by said first portion of said core,

providing annular valve seats for said sealing rings in said second portion of said housing after said core has been removed, and

releasing said sealing rings from said valve member and mounting them in said valve seats.

4. A method according to claim 3 in which the valve housing is cast with internal guide ribs and said valve member is formed with guide studs for engagement with said guide ribs. said valve member being positioned in said core so that said studs lie laterally of said ribs at the time of casting and wherein said valve member is turned after casting so that said studs are in position to engage said ribs.

5. A method according to claim 3 wherein said valve housing is cast with internal guide ribs for the valve member and the valve member is formed with guide studs for engagement with said guide ribs and wherein said valve member is enclosed in said core in a position spaced from said open position of said valve, said guide ribs being formed in the valve housing so that when said valve member is moved to said open position said studs engage said guide ribs.

6. A method according to claim 3 wherein said sealing rings are enclosed in said core at a point extended from the end of said valve member.

Claims

1. A method of manufacturing a valve having a unitary, integrally formed housing comprised of first and second portions with inlet and outlet ports and valve seats located in said second portion, and a valve member movable by an operating means extending through an opening in said housing between a position in said first portion of said housing in which said valve is opened and a position adjacent said valve seats in said second portion of said housing in which said valve is closed, comprising the steps of: manufacturing and completely finishing said valve member, enclosing said valve member in a first portion of a unitary, integrally formed core in the position corresponding to said open position of said valve, said core having a second portion which is shaped so that it includes said inlet and outlet ports and so that it may be provided with said valve seats, fixing said core in a mould for casting, casting said valve housing around said core so as to form said first and second portions of said housing around said corresponding first and second portions of said core, removing said core from said housing through either said inlet or outlet port, and attaching said operating means to said valve member.

3. A method according to claim 1 further including the steps of; attaching manufactured sealing rings to said valve member before said valve member is enclosed by said first portion of said core, providing annular valve seats for said sealing rings in said second portion of said housing after said core has been removed, and releasing said sealing rings from said valve member and mounting them in said valve seats.

4. A method according to claim 3 in which the valve housing is cast with internal guide ribs and said valve member is formed with guide studs for engagement with said guide ribs, said valve member being positioned in said core so that said studs lie laterally of said ribs at the time of casting and wherein said valve member is turned after casting so that said studs are in position to engage said ribs.