US1765021A - Flask section for molding cast-iron pipes and the like - Google Patents

Description

3 Sheets-Sheet l ATTORNEYS J. R. MCWANE Filed March 19, 1928 FLASK SECTION FOR MOLDING CAST IRON PIPES AND THE LIKE TEW June 17, 1930'.

June 17, 1930.

J. R. McwANE 1,765,021 FLASK SECTION'FF. MOLDING GAST IRON PIPES AND THE LIKE 3 Sheets-Sheet 2 Filed March 19, 1928 I INVENTOR,

lll lli ATTORNEYS 'June 17, 1930. J. R. MwANE 1,765,021

FLASK SECTION FOR MOLDING C'AST RON PIPESIIAND THE LIKE 5 Sheets-Sheet 3 ATToRNEYs i u. U M Q. ,RN m QW@ y s L llll -L mmfi-l LA H Nm. Sm. NN Nm. w n@ Patented June 17, 1930 narran? stares Farrar ortica JAMES ia. McwAn'E, on BIRMINGHAM, ALABAMA, AssIGNoR. To McwANn oAsr IRON PIPE COMPANY, or BIRMINGHAM, ALABAMA, A'coRroRArIoN or ALABAMAv FLASK SECTION FOR MOLDNG CAST-IRON PIPES AND THE LIKE Application led March 19, 1928. Serial No. 262,683.

This invention relates to apparatus which is advantageously used for molding long cast iron pipes, although capable of other uses and, among other objects, aims to pro- 5, vide an improved pattern platev and im` proved flask sections cooperating therewith to expedite making multiple molds. The apparatus is preferably employed in connection with the system described and 1@ claimed in my copending application, Serial No. 220,731 filed September 20, 1927.

Referring to the accompanying drawings of a preferred form of the invention Figpl is a top plan view of the drag section of a flask;

Fig. 2 is a fragmentary plan view of the drag of Fig. l;

Fig. 8 is a side elevation, partly in vertical section, of the same,

Fig. 4 is a sectional view taken on the line H of Fig. l and also showing, in dotted outline, a cope arranged on the drag;

Fig. 5 is an elevation of a portion of a jolt rammer with the pattern plate thereon,

the patterns being inv section, and a flask section shown above the `pattern plate in cross section and ready to be rammed;

Fig. 6 is a Jfragmentary side elevation, on

3o an enlarged scale, of the preferred means for holding the pattern plate and flask sections together;

Fig. 7 is a fragmentary top plan view, also on an enlarged scale, lof thel holding means of Fig. 6;

Fig. 8 isa perspective view of the wedge forming part of the holding means of Figo ;V

Fig. 9 is a fragmentary sectionalview, on an enlarged scale of a flask section on a pattern plate; and i Y Fig. l0 is a fragmentary sectional view of one end of the pattern plate showing a guide pin for a flask section.

In the manufacture of cast iron pipe in horizontal molds, by what is known as the green sand process, the practice heretofore has been to use a molding machine having a stripping plate and drop pattern. y@ne section of the flask is rammed ata time, and the rammed sections are removed and matched together with the core bar or bars between them.

There are some objections to the useV of these stripping plates and drop patterns,

the principal objection being that, in theY course of time, the patterns and stripping plates both wear and it is then quite diflicult to keep them properly adjusted. Moreover, in ramming pipe flasks on a jolt rammer, the mechanism of the drop pattern will not withstand rough usage. Therefore,

when lemploying the ysystem heretofore in` use, it has been necessary to ram the flasks byhand, which is laborious, expensive and slow. Y

To speed upr production and to economize in the manufacture of cast iron pipes and the like, it is highly desirable to employ the jolt ramming machines. To use this ramming apparatus successfully, it is necessary' to employ pattern plates orY match plates. kSuch attern lates have one-halfy of the patterns fastened to them and are made so as to permit lifting the flask sec# tions off them A after the jolt ramming. Tn

the process of molding, each pattern plate 1n one operation forms'onehalf of one or more pipe molds and these halves (the flask sections) are subsequently matched to gether, with the cores properly placed'i'n the molding space to make the complete mold.

ln using a pattern plate, it is very difli-Y cult to prevent what is calledv ratting, this being'a sticking of the sand along the edges of the pattern, which results in an imperfectmold. It will be readily understood that' this is much morer easilyv preventedV when the pattern is dropped through the stripping plate away from the mold, Vas in the old process, than itV isy when the flask section, with the molds formed therein,is lifted from a stationary pattern yattached to the. pattern plate.` The present ,inven tion'provides a pattern plateso made as to I To hold the flask section intermediately to the pattern plate, a pair of opposed brackets 36 (Figs. 5, 6 and` 7) are' shown as being bolted to the sides of the pattern plate and have overhanging portions for receiving holding wedgesY between opposed, compound tapered faces thereon and co-acting bosses or pads 38 on the flask section having machined vertical faces. The taper of the wedges is both longitudinal and transverse (Fig. 8) so that when the wedges are inserted between the wedge receiving faces, their thickest portions at the bottom rest against a suitable shoulder 39 on the brackets whereby they tighten themselves automatically when the jolt rammer 40 is reciprocated up and down. The described Wedge means will engage and hold slightly warped flask sections. Moreover, the arrangement is such that the plane faces of the wedges which engage the bosses or pads 38 are also vertical and act as lateral guides for the flasks when they are being lifted from the pattern plate, thus preventing ratting.

After the flask section is thus located on the pattern plate, it is supplied with green sand and the jolt rammer 40 is operated. The section is jolted until the sand is well rammed; then the ramming operation is completed by manually operated pneumatic rammers. To permit the flask sections to be removed from the pattern plate without destroying any part of the mold or without ratting, the patterns 33 (Figs. 5 and 9) are shown as being flattened or cut away adjacent to their junctions with the surface of the pattern plate. If the patterns were not cut away there would be portions of their surfaces adjacent to their junctions with the pattern plate which would be substantially vertical. Hence, there would not be suflicient draft for the patterns to permit the flask sections to be removed without destroying the molds. Herein, the patterns have planed surfaces ll extending `upwardly atan angle of a few degrees from their junctions with the pattern plate to afford ample draft. I have found by many hundreds of trials that it is only necessary to cut away a few thousandths of an inch of the thickness of the pattern, to provide this draft. Figs. 5 and 9 greatly exaggerate the flattened surfaces of the patterns so as to make them apparent. Y j

I have also found that the san-d adjacent to the surface of the pattern plate and around the edges of the patterns is not and cannot be rammed as tightly as the sand in other portions of the molds. Consequently, when the metal is poured, its weight will compress the somewhat looser sand where the flat surfaces appear and thus increase the thickness of the castings so that each is of substantially uniform thickness, with no perceptible flattening anywhere.

From the foregoing description, it -will be seen that the improved apparatus here provided permits rapid preparation of'pipe` molds and the-like practically entirely by mechanical means. There are nopparts of the patterns or flask sections which can be distorted during the ramming operation. Further, ratting and consequent destruction of the molds is practically elimina-ted by the form of the patterns. Also, the flaskv sections are so constructed Vas to .obviate deflections destructive to the molds when they are being handled by a crane. The apparatus makes practically perfect molds and will therefore permit the manufacture of long sections of pipes having thi-nner walls than could be produced by old methods.

Thepattern plate, the wedges and certain co-operating parts are claimed in a divisione al application Serial No. 436,751 filed March 18, 1930.

Obviously, the present invention is not restricted to the particular embodiment thereof herein shown and described. Moref over, it is not indispensable that all the features of the invention he` used ,conjointly, since they may `be employed .advantageously in various combinations and snb-combina,- tions.

What is claimed is J 1. A flask section for the molding ofV a plurality of cast iron pipes horizontally, having provision at itsV opposite ends to be lifted horizontally and double longitudinal strengthening vwebs separating the flask sectionA into pouring units and. arj ranged to prevent destructive Adeflections of the flask when rammed and lifted.

2. A flask section for the molding of a plurality of cast iron pipes horizontally, hav-ing double longitudinal strengthening webs separating the flask sectioninto `pour- 1n thgough the center portion ofthe flask sec,- tion and merging into single webs at .each end thereof.;` and means at .theoppcsite ends Aof the flask'section opposite said single web whereby it may be; lifted horizontally.

3. A flask section for the molding ofa plurality of cast iron pipes horizontally,

Y,having double longitudinal lstrengthening webs separating the flask section into pouring'units, `said webs being joined at their in'- side edge by an integral web; and lifting tri'innions on the Lends of said section alined with said webs.

4. `A flaskpsection for the molding of a plurality of ,cast iron pipes horizontally,

havingy double longitudinal V'strengthening webs separatingthe flask section into pouring units, said webs being joined at their inside edge by yan integral web,- and .the integral web being depressedat intervals beum'ts, said -doublewebs extending Cil strengthen the flask sectionY in the central part and thus obviate such deflection in the Vcentral part as will be destructive of the mold; the space between the branches of the longitudinal web permitting the provision of perforations for the escape of gases formed during casting and freezing of the metal.

6. A Hask section for molding a plurality of elongated castings horizontally7 having a pair of spaced longitudinal webs' dividing the section into pouring units; and a plurality of transverse webs connected to the longitudinal webs,vsome of the transverse webs extending across the space between v`the longitudinal webs. Y

7. A flask section for molding a plurality of long cast iron pipes comprising, in combination, axially aligned trunnionsV at the Y opposite ends; and a strengtheningrweb extending longitudinally of the flask section between said trunnions to obviate destructive saggingof the rammed flask section when it is lifted by said trunnions.

8. A flask section for molding a plurality of long cast iron pipes comprising, in combination, a pairloftrunnions at the ends on the longitudinal vaxis of the flask section;

' and'longitudinal and transverse strengthenside the flask section between the trunnioned ends to resist vsagging of the flask in the middle after it is rammed and lifted from n a pattern.

on the longitudinal axisof the flask section 5' and longitudinal and transverse strengthening webs integral with rthe walls of the flask section arranged to obviate destructive deture. f

Y JAMES R. MCWANE.

flection Vwhen the rammedflask section is lifted or 'transferred from a pattern; said

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