The kettle is shown in [Fig. 36], which represents one capable of heating sufficient seed to keep four 16-plate presses occupied, or to make 6 tons of cake per 11 hours. It is steam jacketed and furnished inside with a damping apparatus. The inside diameter is 5 ft., and the depth 2 ft. 6 in. The seed introduced is kept in motion by the stirring gear, and when sufficiently heated and damped, is withdrawn by the box A in quantities to form one cake, and transferred at once to the moulding machine, attached or separate.
This machine is illustrated in Figs. [37], [38]. Its purpose is to measure the quantity of seed required to make each cake, to shape it as required, and to press it so much, without extracting any oil, as will enable the greatest number of cakes to be put into the press. The measure of seed is placed on a strip of woollen cloth, spread upon a thin iron tray, sliding on the guides B; the bottomless hinged mould C, having the exact shape of the intended cake, is closed upon it, and the measure A ([Fig. 36]), which is also bottomless, is drawn over guides in the upper surface of the mould C, thus accurately distributing the seed. The mould is next thrown upon its hinge ([Fig. 37]), and the ends of the strip of cloth are folded over the seed, the thickness of which is about 3½ in. The thin iron tray, with the mould of seed upon it, is then pushed along the guides B, beneath the die D. This action gives motion to a cam, shown above in the illustrations, but which may be placed beneath if necessary. This cam brings down the die and compresses the mould of seed to a thickness of 1¼ in.; its revolutions are so timed that the seed is under pressure long enough (about one-third of a minute) to let the workman have another cake ready.
Fig. 36.—Seed-boiling Kettle.
When the die of the moulding-machine rises, the cake and tray are removed and placed in the press ([Fig. 39]), the tray being withdrawn. The plates of the press are slightly thickened towards the edges, and bear the name of the
Fig. 37.—Oil-cake Moulding Machine.