US2252963A - Support - Google Patents

Description

Aug. 19, 1941. F. A. FAHRENWALD SUPPORT Filed Oct. 27, 1938 2 Sheets-Sheet 1 a/am Inverfuor: Fimfli 411mm 'enwold Q9 75% Aid, h s.

Patented Aug. 19, 1941 UNITED STATES PATENT @FFICEL 2,252,963 v SUPPORT Frank A. Fahrenwald, Chicago, Iii. Application October 2'7, 1938, Serial No. 237,297

5 Claims.

My invention relates to enameling and analogous processes where articles to be subjected to a high degree of heat are passed through a furnace, either continuously on a traveling belt, or step by step by means of some sort of pushing arrangement. It includes among its objects and advantages a material reduction in the relative weight of the support proper for supporting such an article during heat treatment, together with increased resistance to the disintegrating action of repeated heating and cooling.

Further objects andadvantages of the invention will become apparent as the description proceeds.

In the accompanying drawings:

Figure 1 is a perspective view of a supporting unit according to the invention;

Figure 2 is a section on line 22 of Figures 1 and 3;

Figure 3 is a section on line 3-3 of Figures 1 and 2;

Figure 4 is a section on line 4-4 of Figure 2;

Figure 5 is a sectional view of a modification;

and t Figure 6 is a section on line 6--6 of Figure 5.

In the embodiment of the invention selected for illustration in Figures 1 to 4, the individual uprights H] are first cast separately. Each such upright has a flaring base at l2. A plurality of such uprights are material of the I beam I4 is cast in that mold with bosses or enlargements l6 adjacent the base [2 of each upright, which enlargements receive and grip the bases.

In the embodiment of Figures 5 and 6 the round uprights l l are cast in one piece with the metal of the I beam [5.

In either instance the bottom beam includes an upper flange l8 and a lower flange 2|] connected by a web 22.

As compared with the heavier structures of the prior art, the supporting means so far described embodies no adequate base for maintaining the parts in the upright position. In Figure 1, I have indicated two beams l4 positioned a considerable distance apart and interconnected by cross rods 24 passing through aligned holes drilled in the bases of the bosses It. In this way a wide variety of units can be quickly assembled from a stock of I beams with cast-in uprights l0, and a supply of simple round rods 24. In the one piece embodiment of Figures 5 and 6 the stub arms 30 are channel-shaped and the cross piece 32 is simply laid in and fastened with rivets 34.

then laid in a mold, and the When such supports are used in enameling ovens, the tops of the uprights H] are pointed as indicated at 20, and for a short distance below each point, the edges of the upright are beveled a little as indicated at 28 to avoid any collection of dust which might get hold of a sharp edge and tend to injure the enamel ware by blowing up against it. Because such an assembly as I have disclosed weighs only a fraction as much as previous supports for the same purpose, a very large heat saving is accomplished. The significance oi this will be more apparent when it is considered that in many instances the supporting means weighs more than the article supported, but it is necessary to heat both of them to the high temperature to which the supported article must be subjected, and the subsequent withdrawal of the article and support from the furnace represents a loss of the heat delivered to both.

In service, supports of this sort promptly build up a black coating of oxide, commonly believed to be chiefly chromium oxide, and this oxide tends to spall off in tiny almost microscopic flakes which get into the enamel and cause discoloration and blemishes. The use of nickel up to 60% materially obviates this ditficulty.

However, in such high nickel alloys in which the carbon is relatively high, say from 0.50% to 1.20%, another difficulty is encountered in that the irit, where it contacts the sharpened point of the support, corrodes the sharpened point rapidly so that the point has to be resharpened frequently and the life of the support is materially reduced. Whether this corrosion is primarily by dissolving the oxide coating at the top is not certain, but it is believed that this action is primarily responsible. In any event, the use of carbon below 0.30% and preferably as low as 0.25% very materially reduces the corrosion by the frit at the supporting tip. The analysis resulting from the experimentation supporting the foregoing statements is to 65% nickel, 17% to 21% chromium, and not more than 0.30% carbon; the balance iron with the usual metallurgical impurities. The percentage I prefer is nickel, 18% chromium and carbon 0.25%, but any alloy within the range stated will be outstanding in its resistance to the corrosive action of the frit.

Without further elaboration, the foregoing will so fully explain my invention that others may, by applying knowledge current at the time of application, readily adapt the same for use under various conditions of service.

I claim:

1. In a furnace support, an I beam'having a vertical web and horizontal top and bottom flanges not greater in horizontal dimension than twice the thickness of the web; a plurality of pre-cast uprights embedded in and projecting upwardly from the beam; said beam having transverse holes drilled therethrough to receive cross bars.

2. In an enameling furnace support: an upright having a conical point at the top; said upright being of substantially rectangular horizontal cross section below said point; the vertical edges of said upright being beveled adjacent said point.

3. In an enameling furnace support: a horizontal beam of I cross section with the web vertical; and uprights extending above said beam to support articles to be enameled.

4. In an enameling furnace support: a horizontal beam of I cross section with the Web vertical; said web having a thickness substantially half the flange width; and uprights extending above said beam to support articles to be enameled.

5. In an enameling furnace support: a horizontal beam of I cross section with the web vertical; said web having a thickness substantially half the flange width; and uprights extending above said beam to support articles to be enameled; said uprights having a thickness substantially the same as said web.

F. A. FAHRENWALD.

Images