US1895135A - Water-cooled mold - Google Patents

Description

w. ROHN WATER COOLED MOLD Filed OG'C. 7. 1930.

Jan. 24, 1933.

2 Sheets-Sheet 1 J'n ventor Alarm/y J Jan 24, 1933.

w. RpHN WATER GOOLED MOLD med Oct. 7. 1930 2 Shuts-Sheet 2 Comma Jnven'to'r:

Ewan.-

Patented Jan. 24, 1933 PATENT OFFICE.

mam nonmor mnv-oiw-rnn-nnm, GERMANY WATER-COOKED MOLD Applicationflled October 7, 1930, Serial 1T0. 487,084, and-1n Germany July 8, 1989.

This invention relates to water-cooled ingot-molds, more especially to water-cooled molds formed by an inner and an exterior tube between which ribs for guiding the coolin medium are provided.

%he object of my invention is to provide molds of this kind in which a satisfactory transmission of heat from the inner tube to the cooling medium is warranted.

The invention is illustrated in the annexed drawings, of which Figure 1 is an-fiaxial section of a coollng mold according g't'o the invention.

Figure 2 is "a cross section and shows a modification of the cooling ribs. D

Figure 3 is a cross section similar to Figure 2 and shows a further modification of the cooling ribs.

Figure 4 shows a detail, namely a screwshaped body for insertion in the cooling passa es.

igure 5 shows an arrangement for exchanging the inner tube.

Figure, 6 is an axial section) showing a modified form of acooling mold according to the invention.

Figures 7a and 7 b show difierent forms of construction of the band for forming the which is adapted to define the cast molten metal. The ribs'b which guide the cooling water, are not formed integral with the inner mold wall a, but on the contrary may either be independent or connected to the outer casing c. The ribs 6, which guide the cooling water, are sharpened on their side turned towards the actual mold wall a so as to form cutting edges whereby contact between a and 6 only takes place along a suit-.

ably narrow line. Inthis manner there is obtained the result that the actual mold wall a does not have any points at which the passages of heat from a to the coolin water is liable to be defective. As shown in Figure 2 the cutting edge of the guide ribs b may be partly removed whereby the ratio between remaining ortions of the cuttin edges and the remove portions ma be di erently selected. In many cases t e cutting edge of the guide ribs 6 may preferably have an appearance similar to saw teeth. With such an arrangement the inner mold wall a is held and supported effectively at the points d, (1, while between these points narrow slits '65' e, e are provided between the mold wall a and the ribs 6 through which a small quantity of water can pass from the cooling passage I directly into the cooling passage II parallel to the main axis of the mold. In the accompanying drawings the width of these slits is magnified to be some what clear-' er. By suitably selecting the separate dimension it is possible for all the points of the inner mold wall a to be in contact with, water in a substantially uniform manner, and that no points are present where there is a lower removal of heat. A very efiicient utilization of the whole cooling capacity of I the water which flows thru can, in this case, be obtained in that propeller-like guide bodies 7 (Figure 4) are inserted in the separate cooling passages so that a whirling movement is superposed on the flow of water in the main direction of flow.

When constructing the molds in the described manner the outer casing c and the cooling ribs 6 need only be produced once, while the inner mold, which is very inexpensive by reason of its shape, can be exchanged in a short time. This exchange can, forex-i ample, be effected in the-manner illustrated-1'?- in Figure 5 in which 9 indicates a flange provided on the outer casing c and a is again the inner mold wall. Into a recessbetween both parts there is fitted and endless rubber ring 5., for example of circular'cross section, which is so compressed by the pressure-of the flange i, acting as a stufling box, that a water and pressure tight closure is obtained between the inner mold wall a and the outer casing c. For a round mold for a caplaclty of for example 100 kg., efiective lengt 850 mm. and an internal diameter of 140' mm. there is used as the inner member a seamless copper pipe of mm. wall thickness-and which only weighs about kg. Its renewal does not require any greater expense than the difierence in rice between new copper and old copper. have been formed at a casting temperature of 1650 C. in pieces amounting to more than 2,000 without the least damage to the inner copper pipe noticeable, while the usual molds made of hematite cast iron used for Eiing made by casting.

In some cases the manufacture of the molds may be simplified by forming both the jackets of the molds and the guiding ribs from rolled material, whereby the manufacturing costs are considerably reduced and, on the other hand, it is rendered possible to exchange the guiding ribs if required. 'Moreover, another advantage is attained inasmuch as the jacket of the mold may be made from one single piece closed initself, whereas a mold as shown in Fi e 1, for instance, is preferably made of t ivo longitudinal halves which are connected by flanges.

A mold of this kind is illustrated by way of example in Figures 6, 8, and 9 of the drawings. In this case as an outer casing a pipe l is used and the guide ribs for the cooling water are formedby a suitably shaped band an surrounding the mner pipe k of the mold.

An example of construction is illustrated in Figure 6, while Figures 7 a and 7?) show by way of example forms of construction of the strips m and m before being spirally wound around the pipe forming the actual mold. The spiral path formed by the strips m and m" may for example be simply fitted into the pipe formin the outer casing, and if necessary soldere to this at points or thruout the length thereof.

The spiral path may also be stifiened before inserting 1t intothe outer pipe by rods 11.

extending therethru as shown in Figure 8 or by means of longitudinal strips 0 as shown in Figure 9, whereby it is not necessary to secure them to the outer pipe or preferably only to secure them at a single point or some few spots. If the shape of the blocks to be formed is conical the inner mold pipe may, for example, be readily broughtinto the desired shape, for example, by forcing over a conical mandrel.

In order to enable the outer casing to be formed from a cylindrical pipe the guide strip adapted to be wound spirally is in this case preferably made conical, that is to say such molds steel blocks be screwed or fitted into position. The insertedouter ring which is screwed in position, or which is tightened by se arate screws when an internal screw threa is not provided, compresses the rubber packing and thus formsa fluid-tight joint.

- It is also possible to screw'at one of the ends of the pipes provided with an external thread, a flange or plate 1' which may serve for the reception of crane eyes 8 or securing devices for the base plate. I

If the mold is to be used for oscillating castings or centrifugal casting it is possible during the same operation as the cutting of the screw thread to turnthe bearing surfaces for the bearin These however may a so be provided in t e flanges which are screwed in position. H

It is preferable also to providea device for tightening and releasing the base plate and for removing the blocks from the mold. This device may consist of a guide rod t (F ig ure 11) bent in two directions, which for example can be pressed into position and released by means of an eccentric u with or same time is capable of bemg swung laterally or roller b'ea'rin so as to conveniently release the base plate 'v and the ingot which has been cast.

The above explanations have been giyen in connection with a conical mold, but it'will be understood that the same principles of constructions can be applied with the same or greater advantage to mol'dsof any other suitable shape e. g. for flat billets to be rolled into strips or sheets. If the heat conductivity of the metal to be cast or one of its properties renders it necessary an inner pipe of a meta-bother than copper may be used or substituted therefor. v

This extremely simple and inexpensive yet very suitable type of mold is also adapted as an element for casting machines in which a number of such molds are mounted together on a, turn table or on another returning conveying appliance with or without an oscillatingdevice for the separate molds as illustrated in a schematic manner by Figure 12.

According to this figure the molds A concharges of many thousands of, kilogrammes mechanically into small ingots by avoiding the tedious movement required for conveying and carrying-the ladle with the liquid metal into accurate relative position to every single mold. These small ingots can subsequently without any rough or preliminary rolling be treated directly .in continuous rolling mills so as to shape the final product.- The ingots mechanically cast'into a cooled mold show an excellent fine and uniform casting structure. If these cooled molds are oscillated during casting metals and alloys, which normally have a casting structure little suitable for rolling, acquire such a satisfactory structure that the ingots can be directly subjected to a continuous rolling mill without liability to disturbance. 7

The inexpensive production and easy capability of exchange of the actual mold forming the featureof the Figures 1-5 and the additional feature of constructing the outer casing substantially of. a simple internally smooth pipe and the formation of the partitions and ribs from spirally wound strips for guiding the water and which on the inner side are sharp edged or are pro-' vided with sharp edged projections, constitute the essential features of the present invention.

I claim V y I 1. A water-cooled ingot-mold having a thin wall of'suitable metal adapted. to surround the ingot to be cast, comprising a ack- '35 etand ribs for guiding the cooling water arranged in the space between the said wall and jacket and forming a helical path for .the cooling medium, the said ribs being formed on the side turned towards the inner wall as a cutting edge. V

2. A water-cooled ingot-mold having a v thin wall of suitable metal adapted-to sur 'round the ingot to be cast, comprlsing a jacketand ribs for guiding the cooling water arranged in the space between the said wall and jacket and forming a helical path for the cooling medium, the said ribs being formed on the side turned toward theinner wall as acutting edge, and the latter being partly cut away to form direct passages from one to th'e next winding. 7

In testimony whereof I aflix my s' ature.

- WILHELM R

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