US1798649A - Rotary furnace - Google Patents

Description

March 31, 1931. BARTUNG 1,798,649

ROTARY FURNACE Filed Nov. 23, 1928 2 Sheets-Sheet 1 March 31, 1931. BARTUNG 1,798,649

ROTARY FURNACE Filed Nov. 23, 1928 2 Sheets-Sheet 2 Inventor:

Patented Mar. 31, 1931 UNITED STATES PATENT or ice FRIEDRICH BARTLIN G, MUNICH, GERMANY ROTARY FURNACE Application filed November 23, 1928, Serial No. 321,444, and in Germany December 9, 1927.

United States patent application Ser. No. 113,288 which was filed by me jointly with Ludwig Honigmann describes a rotary annular tray furnace for constant heat treatment of loose material, with a tray rotating in an annular furnace chamber and supported by a travelling frame mounted outside the furnace chamber, and the invention is substantially characterized by the insertion between the working tray and the travelling frame, of joints by means of which the tray rests on the travelling frame.

The said prior specification is the first disclosure that the connection, which up to that time was rigid, between the travelling frame and the working tray of a rotary annular tray furnace, should be broken by joints, for the purpose of rendering harmless the unfavorable infiuence of the very considerable difference of temperature between the parts of the structure (working tray and rotary frame) which hitherto has been rigid. As stated in the above-mentioned specification, this injurious influence made itself felt by unpleasant stresses in the whole tray construction, which were liable to lead to wearing out of material and also to seizing or jamming during working. Moreover, the possibility is attained of keeping the working surface of the annular hearth completely horizontal independently of the travelling frame, and perfectly flat.

The necessity of keeping the working surface of the annular hearth flat becomes obviously greater and greater, thethinner the layer in which the material to be treated is placed on the hearth surface.

United States Patent No. 1,640,502 dis closes the new technical rule that the material to be worked, when subjecting fuels or the like to low temperature distillation,

should be put on in layers of which the thickness amounts to only fractions of a centi meter. This results in very material advantages for the low temperature distillation,

more particularly as regards uniform, thorough and quick working, as well as regards the products obtained. Obviously, for such a process it is an indispensable condition that 501 the working surface shall be maintained perfectly straight as otherwise the uniform depositing of such thin layers is impossible.

The object of the present invention is still further to improve the arrangement previously proposed, in the sense of keeping the working surface perfectly straight. According to the invention, a rotary annular tray furnace for constant heat treatment of pulverulent or fine grained material in a very thin layer, in which the working trays and travelling frame are connected together by joints, is characterized by the arrangement on a joint supporting tray which is supported bythe travelling frame and closes the annular furnace chamber at the bottom,.of several inde pendent concentric annular working trays with the insertion of joints. This ensures that the working surface proper of the annularhearth is completely relieved from the influences of the stresses and movements appearing in the travelling frame or also in the supporting tray closing the'furnace.

In the same withdrawn from the influences-of the differ ence of temperature between the outer space and the furnace chamber. Further, however, owing to the subdivision of the working hearth into concentric annular surfaces of relatively modest width, the whole working surface isfsubdivided into narrowsections, so that these single sections are also protected from mutually influencing one another. It is obvious that the wider a rotating hearth surface is, the greater will be the tendency to. bending and warping of the surface.

Experience has shown that a working surface constructed in the manner described, is suitable for placing'on it thefmaterial to be treated in layers, of even one millimeter, and less, thickness, in a uniform manner.

In a preferred construction according to the invention, the supporting trayv can rest with its outer and inner edge, with'the in-' sertio-n of joints, each edge on a separate annular travelling frame. This ensures that the supporting tray will be kept absolutely flat and horizontal, and. the well-known easy up and downswinging of the rotating tray is avoided. The joints inserted between the travelling frames and the working trayenway, the working surface is' able the tray to assume automatically an absolutely horizontal position even when irregularities appear in the travelling frame during the working.

Moreover, according to the invention each working tray can be traversed by a heating fine or conduit so that its heating can be regulated in the finest possible manner independently of the adjoining working trays. These heating fines are provided according to the invention with heating medium inlets and outlets which are connected each by a joint swivelling pipe to a central stationary pipe.

A construction according to the invention is diagrammatically illustrated by way of example in the accompanying drawing, which shows? Fig. 1, a vertical radial section, of the same.

Fig. 2, a top plan view, with portions broken away.

Fig. 3, a fragmentary section of the tray and its support, substantially on line 3-3 of Fig. 1.

Fig. 4,

stantially The furnace in a similar fragmentary View, subon line t-et of Fig. 1.

the constructlon illustrated has, inaddition to the advantages just mentioned, also the advantage that it can be very light and movable, so that it can be very easily erected and dismantled again. Beside the central supply and discharge pipe for the heating medium, only the furnace hood a stationary. This hood is of the known U- shaped cross-section open at the bottom. Its outer and inner edges terminate in vertical ribs a a which dip in the known manner into sand troughs b which are secured to the rotating hearth and are intended to form a tight joint of the furnace chamber outwardly. The remaining furnace parts are combined to a jointed annular body which rests on two annular travelling frames 0 each of which is rotatably mounted by means of rolling brackets e on a separate rail track (7. The drive is in the known manner by means of the counter'shaft 7". On both travelling frames 0 is mounted the supporting and closing tray 9 namely by means of joints' comprising the rockers h and the bearing pin it located therebetween arranged at suitable distances-apart. These joints render possible a mutual adjustment between the tray 9 and the travelling frames. Above the supporting tray, at a suitable distance above the furnace hearth, are arranged several (in the construction illustrated three) concentric annular trays i '5 i Apart from the fact.

that these trays have different diameters in order concentrically to rotate ata suitable distance from one another, they are made completely identical. Each of them rests on the supporting tray 9 by means of joints comprising rockers k and the pivot pins k which allow of an adjustment relatively to the said trays.

It will be noted that the jointed connections between the rolling brackets e and the supporting tray, and between the supporting tray and annular trays, have horizontal axes and are arranged chordally with respect to the circles of the annular furnace chamber and the trays.

Each of the trays is hollow. The hollow space Z is used as the heating flue. The supply of the heating medium takes place through pipes on which must of course have a jointed or flexible section mc opposite the joint 76. They all open into a jointed admission pipe 71 which is radially directed and rotates ith the annular hearth about the centre of the latter. Identical'outlet pipes open into the joint outlet pipe 0. The inlet pipe 71 and the outlet pipe m open into a stationary column-like central pipe p pro-.

vided with an inlet Q and an outlet 1 hat I claim is 1. A rotary annular tray furnace for con tinuous heat treatment of pulverulent or fine-grained material in a very thin layer and including an annular furnace chamber,

comprising a traveling frame, a supporting tray closing the bottom of the furnace chamber and carried by said traveling frame, a plurality of independent concentric annular working trays located in the furnace chamber, and independent horizontal chordal jointed connections between said supporting tray and said working trays. V

2. A rotary annular tray furnace for continuous heat treatment of pulverulent or finegrained material in a very thin layer and including an annular furnace chamber, comprising inner and outer traveling frames concentric with said chamber, supporting tray closing the bottom of the furnace chamber, independent horizontal chordal jointed connections between said tray and frames, at plurality of independent concentric working trays located in the furnace chamber, and independent horizontal chordal jointed connections between said supportin tray and said working trays. q

3. An annular tray furnace as in claim 1 including an independent heating fine for each working tray, a common fixed inlet for renting medium coaxial with said trays and furnace, a common inlet conduit jo-intedly connected with said inlet and moving with the trays, and independent jointed connecgions from said conduit to said inde iendent ues;

In testimony whereof I have signed my,

name to this specification. I

FRIEDRICH BARTL NG.

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