Modern Gasworks Practice

THE HORIZONTAL RETORT BENCH 85 (strengthened by webs) by means of which the bar is suspended from the support,ing or cross bars. The central portion is convex, so that the fuel resting upon the grate is held away from the point of attachment of the hook end. The lower end of the hangpr bar is bent round, and (wrapping round the triangulär portion of the supporting bars) efEects a locking action, which. prevents the bars from becoming disengaged during the process of cleaning. To the back of the bars is cast a web, provided with two holes, into which a Y-shaped rod may be inserted when the removal of the bar is necessary. The bars are suspended from supports, which are cast with parts alter-nately triangular and round in cross section, and provided with square extremities to rest in the supporting boxes. The bars perform a double function in that (as the triangulär portions protrude beyond the circular portions upon which the hanger bars are suspended) each banger bar is maintained in its right position, while the lower end of the hanger bar engages with the base of the triangulär portion of the supporting bar, and efEects the locking action referred to. At the same time, while th.e hanger bars are locked when in their working position, each may at any time be unhooked and removed by dis-engaging its lower end from the triangulär portion of the cross bar by applying to the lower end a slightly forward movement. The most economical method of working is to arrange for the attendant to gently shake up the fire in between the Grille spaces every eight or twelve hours according to the purity of the coal employed. For this purpose a light pricking bar, made from i!-incli round iron with a 1-inch chisel head is used. At the same time a long-handled shovel should be inserted into the base of the fuel-bed beneath. the bottom row of hangers, and the dead material should. be removed. The amount of steam required depends entirely upon the quality of the coke employed. In the simple form of grate, where the primary air is taken in. under vacuum in the ordinary way and steam is admitted through the cheeks of the producer, a liberal amount of steam should be admitted when first getting to work. This should th.en be gradually reduced until the amount is just sufficient to ensure that no hard clinker is formed, but that all the inert material is obtained in the form of dust. When the new pressure system is employed the exact quantity of steam required for the best results must again be found by trial and effect. For instance, when. the producer is put on to regulär working a liberal amount of steam should again be admitted at first, and the air-regulator should be set so that the requisite quantity of air is impelled. It should be remembered, however, that when the steam is gradually reduced the injector effect is also reduced, thus it is necessary to open. the air-regulator slightly in order that sufficient air may be taken in. Experience has shown, however, that once the proper adjustment is obtained it need scarcely ever be interfered with. With all types of sloping grates, whether they be of the ordinary step pattem or the Grille type, it is essential that the fuel in the producer should be kept as deep as possible. Whereas water is employed for cooling the ordinary step grate it sh.ou.ld be remembered that it is harmful not only to the working of the Grille grate but also