US2061300A - Processing roll and method of producing same - Google Patents

Description

Nov. 17, 1936. F. c. T. DANIELS PROCESSING ROLL AND METHOD OF PRODUCING SAME Filed Aug. 22, 1934 2 Sheets-Sheet l alloy sfee/ oll cash/27 Patented Nov. 17, 1936 PRGQESSENG WOILL AND METHQD GE PJRKBDKJQDHNG SAME Fred C. T. Daniels, Pittsburgh, Pa. Appllication August 22, 19%, Serial No. 740,903

11 (Claims.

My present invention relates to a processing roll as a new article of manufacture and to a method of producing the same.

In the rolls hitherto used for the processing papers, fibre board, vegetable oil compounds and various synthetic compounds, there have been certain inherent defects present which the industry has never been able satisfactorily to overcome. Such rolls were either inherently weak, due to their chilled iron construction, or

were difficult to make with uniform wall dimensions free from imperfections and sufiered during their manufacture from the formation of considerable gas under pressure. In addition, these rolls, which were generally made with a sand core, were frequently damaged in removing the sand core, which, due to .space limitations, was rather difficult to remove cleanly. Again, these cores often fused to vitreous glassy masses during the use thereof.

' Accordingly, one of the objects of my present invention is to produce a processing roll which shall be free from those inherent defects and disadvantages present in connection with rolls of prior types.

Another object is to produce a roll which is made of cast steel with either or both of its ends unitarily forged.

A further object resides in casting a steel roll with a cylindrical body portion having an extension at either or both ends and thereafter forging down either or both extensions to form unitary journals and to provide a roll which is strong, uniform as to wall sections, easy to separate from the sand core and which is so produced as to be unaffected by generated gases during the casting operations.

More generally, an object is to improve prior hardened to any desirable extent and by any conventional method.

Other and further objects and advantages will either be understood by those skilled in this art, or will be apparent or pointed out hereinafter.

In the accompanying drawings I have illustrated the present invention in such manner that a direct comparison can be made between prior rolls and the present type of roll which 50 is an improvement thereover, and in such drawings:

Figure 1 illustrates an ordinary hollow chilled iron roll of relatively great wall thiclmtSt and 55 of relatively small bore;

of such materials as rubber, textiles, linoleum,-

known rolls and to enable such to be surface Fig. 2 represents a hollow cast alloy steel roll of thinner wall section and larger bore;

Fig. 3 represents a casting from which the roll of Fig. 2 is machined;

Fig. 4 illustrates one end of a cast steel roll body with a rough cast cope end or extension ready for forging in accordance with the present invention;

Fig. 5 illustrates the result of the nextv step after Fig. 4 with the cope end forged down ready for machining; and

Fig. 6 illustrates a roll provided with reduced roll necks for 'use with anti-friction (roller bearings.

Similar numerals designate corresponding parts in several views.

Extensive studies and investigations have convinced me of certain fundamental deficiencies inherent or latentin prior known and used processing rolls. For example, (Fig. l) a chilled iron roll it with relatively thick walls ii of bodies and journals is inherently weak because the material used has well-known limitations. It is weak and brittle and does not have great tensile strength or elasticity, and these defects are not remedied by the presence of the thick wall sections, which in fact act as an additional handicap in that the bore l2 of such a roll is necessarily rather small and hence dimculties arise in casting the same and in removing the sand core cleanly after the casting operation.

It has been attempted to overcome these erraculties by means of a hardened cast alloy steel roll i5 (Fig. 2). Such a roll is greatly superior in strength and at the same time permits of a reduction in wallthickness, say from 5 inches to 3 /2 inches on a 26 inch roll, while still producing a roll which was stronger than the heavy wall chilled iron roll it described above. These alloy steel rolls it are cast in sand molds and the inside of the roll is formed by means of a I sand core. The bore is indicated by the numeral i6. I observed. that in casting these rolls the molten metal which is fed into the mold at the bottom or drag end is forced upward through the narrow space between. the sand core and the sand mold until the mold and the sinkhead above are completely filled (see Fig. 3 which is the casting required for the roll of Fig. 2). cumstances, as soon as the molten metal passes over the core, a large amount of gas is generated therein due to either combustionor volatilization of the organic matter, etc. in the core. Even though this gas is let ofi through vents in the core and discharged at the top, a considerable top and while the metal was solidifying in the mold and thus caused formation of holes in the roll. can be very readily understood when it is considered that in a typical example the inside bore diameter of the roll body Ill is 19 inches, while the bore diameter of neck i8 is only 10 inches. This constriction of the bore not only resulted in the above, but meant considerable difficulty in removing the core cleanly. Numeral i9 indicates the pipe which forms in the top dur ing solidification and which is eliminated when the sinkhead is removed. Various schemes have been tried to overcome this difiiculty, such as different core mixtures and mixtures of sand or other refractory materials with various organic or inorganic binders. Again, it was attempted to encase the core in a metal casing to prevent this escape of gas and to permit the making of the core with a more refractory material with a minimum amount of gas-forming binder and so,

as to facilitate cleaning out the core itself.

None of these schemes has been successful, although some of them have been improvements over preceding rolls in some respects.

It has also been attempted to make these rolls by casting the bodies and drag end journals in one piece. In this manner the cores could be made straight up through the sinkhead, avoiding constriction. The journals for the cope end were made as a separate casting and then shrunk, keyed-and welded to the body. While this over-= came casting difficulties and produced a roll with a perfect body, nevertheless in service the mechanical fit between the body and cope journal frequently worked loose and rendered the rolls useless.

Hollow forged steel roll bodies and separate forged steel journals have been made and assembled similar to the above, but these too have failed in service because the joints also worked loose in use. It is accordingly apparent that there is a real problem here which has not been satisfac torily solved by the many varied attempts to overcome the known difficulties.

I have discovered, according to my present invention, that I can produce a roll for processing materials, such as those above enumerated, which is not only free from the foregoing and other defects and disadvantages, but which is perfectly satisfactory both from a process standpoint and from a product point of view. Such a roll has a long trouble-free life, has no inherent or latent defects or weaknesses and involves no difliculties in manufacture. It can be produced with uniform and strong wall sections without unnecessary weight and hence can be produced with a higher percentage yield of good metal and thus more inexpensively because I avoid the necessity of using a massive sinkhead for feeding the roll as shown in the light sinkhead of Fig. 4 in contrast to that of Fig. 3.

In forming the roll of the present invention as particularly delineated in Figs. 4 and 5, I cast the drag end (not shown in Figs. 4 and 5) and the roll body together with a unitary cope end or extension, the body and cope end being cast as a straight or substantially straight cylinder 20 having a relatively large bore 2| throughout.

Instead of cutting off the sinkhead 20a at the line 23, as in prior practice, and mechanically fitting in a separate journal, I rough forge the sinkhead to about the shape of Fig. 5 from the,

rough casting of Fig. i. Thus, directly from the rough casting, I rough forge the sink-head to approximately the shape of the journal. 2%. Such procedure additionally provides excess metal in the form of an. annular ridge or head 23 which I find to be especially valuable and useful in that, during the forging operations, I at all times have plenty of metal and can better form a strong, uniform and long-lived roll with no point of weakness at the critical junction as possible excessive thinning of the wall at the junction is eliminated. This rough forging also directly forms a solid journal which is advantageous in those instances where solid journals are desired or required. Hence, no operations are required such as drilling and plugging the ends to form. solid journals.

To finish the roll I need then only machine it to final form and dimensions since the drag end and roll body proper have already been cast to approximate size and shape. If a hole or bore is desired orrequired in the forged journal, for example, for circulating a cooling medium such as water or oil, I may forge the journal on a mandrel of suitable size, thus also producing hollow' journals without extra operations or expense. I could of course, .drill or machine out the solid journals to produce a bore if I so desired.

A roll according to my invention is therefore characterized by freedom from known defects and disadvantages of prior products and processes, by freedom from brittleness or weakness since strong ductile materials can be utilized, by

relatively thin and uniform walls, by a large bore easy to clean and by the capacity of being more efficiently made at less cost per salable unit.

This roll can be made of any suitable or known material which can be forged or swedged under a press, hammer or the like. I might, for example, make the roll from high carbon alloy steel possessing air hardening qualities where I wish machinable steel and then locally surface hard.-

ened. I may, however, utilize a high carbon alloy steel, hardened prior to the machining of the corrugations, but in this case, of course, the hardness is limited to that which can be machined.

In a modified form of the invention I cast a single straight cylinder with an extension at each end and then, in accordance with the teachings above set forth, I forge a journal on each end of this body portion. Such a cylinder can be sand cast according to usual foundry practice or it may be centrifugally cast or hollow forged.

In addition to the elimination of the defects and disadvantages of priorrolls as above outlined and in addition to the advantages herein above pointed out for the present roll, there are other advantages from a. manufacturing standpoint. The large core extension through the cope end makes the whole core strong and rigid and permits it to be held firmly in place, thus enabling me to produce walls of uniform thickness. This also permits free access to the core and renders easy the subsequent cleaning out thereof. The relatively large volume of sand making up the core prevents it heating up too much when the casting is made, thus avoiding fusion of the sand into a vitreous or rock-like structure. The percentage yield of good metal is increased from 15 to by my process and in the case of a 26 inch roll, such as that of Figures 3 and 4, 1500 pounds of metal are saved in making each roll. a

My process and roll is especially valuable for manufacturing rolls to be used with roller bearings (see Fig. 6) which, because of the large space occupied by them ,in comparison with standard bearings, renders necessary a much smaller di ameter of journal. This would involve a still smaller diameter sand core extension through the center of the journals, if prior practice were to be followed, and such; has been found to be almost entirely impracticable by any straight casting process. However, by forging the ends in accordancewith my present invention the diameter of the journals can be reduced as small as desired without any difiiculty. Such a roll with small forged hollow journals 24 is shown in Fig.

6 which otherwise does not vary from my above invention.

The above is intended to be illustrative rather than limitative and the scope of the invention is rather to be defined by the subjoined claims. My invention is applicable to any size or type of roll and to any material so long as it can be cast or swedged. The invention comprises both a roll with forged ends and a process for making the same and these ends may be either solid or hollow and of any required size. The invention may be applied to either end or toboth ends of the roll.

What I claim as new and desire to secure by Letters Patent is:

1. As a new article of manufacture, a hollow processing roll comprising a cylindrical cast body portion and a cast and pressed end unitary with the body portion.

2. As a new article of manufacture, a hollow processing roll comprising a straight cylindrical cast body portion, one east end and one cast and pressed end, both ends being unitary with the body portion.

3. As a new article of manufacture, a hollow processing roll of cast steel with relatively uniform and thin walls free from imperfections andhaving a cast drag end unitary with a cylindrical cast body and a cope end which is unitarily pressed from the end of the body.

4. In a process of manufacturing a processing roll for industrial purposes, the steps comprising casting a hollow cylindrical steel roll body and sinkhead of relatively thin and uniform wall thickness free from imperfections due to casting, and forging the sinkhead to'form a journal.

5. In a process of manufacturing a processing roll for industrial purposes, the steps comprising casting a hollow cylindrical steel roll body and sinkhead of relatively thin and uniform wall thickness free from imperfections due to casting, and forging the sinkhead to rough shape to form a journal, the forging of the cope end being so carried out as to produce a solid journal.

, 6. In a process of manufacturing a processing roll for industrial purposes, the steps comprising casting a hollow cylindrical steel roll body and sinkhead of relatively thin and uniform wall thickness free from imperfections due to casting, and forging the sinkhead to rough shape to form a journal, the forging of the cope' end being carried out upon a mandrel so as to produce a hollow journal.

7. As a new article of manufacture, a hollow thin-walled cast steel roll with one or two reduced ends and having such characteristics as are imparted thereto when a cylindrical cast steel body of suitable composition is cast with a drag end in the rough shape desired and a rough cope end as a body extension, the rough cope end is reduced to form a rough journal and the roll is machined to final shape and size.

8. A process of manufacturing a hollow roll of the kind described comprising unitarily rough casting a drag end, a roll body and a cope end as a body extension, rough forging the cope end in such manner as to reduce it to approximate final shape and size while leaving an excess of material at the junction between the body and cope end to avoid possible excessive thinning of the wall during forging and thereafter machining the entire roll to final shape and size.

9. A hollow processing roll comprising a roll body and two journals, all formed unitarily, the roll body and one end being characterized by having been cast to approximate size and shape with the other end as a cylindrical extension of the roll body, which extension was then forged or swedged down to form a journal, the whole roll being characterized by great strength and by uniform thin walls free from imperfections due to casting.

- 10. As a new article of manufacture} a hollow processing roll comprising a cylindrical cast body portion and a cast and pressed end unitary with the body portion, the roll body having a uniform relatively thin wall section free from casting imp'erfections and characterized by relatively great strength. i

11. As a new article of manufacture, a hollow

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