4. Straight line between terminals.—All manufac turing touches the outside world at two points—the receiving and shipping departments. These are the terminals of the road; and the simplest and best lay out, other things being equal, is a straight line between these two points. Where the plant has only one con nection, as one street or one railroad siding, the routes must generally constitute a circle, so that the start and the finish will be at the same point, or a U or series of U's, both ends of which touch the outside world. When, however, other exits are possible, re ceiving and shipping need not unduly influence the routing, but may be located so as to facilitate manu facture. As soon, however, as these elementary con ditions of the location of the "industrial terminals" are passed, there appear more important complica tions which affect the routing.
5. V arious types of manufacture.—All manufac turing is analytic, continuous, assembling, or more often a combination of all three processes. Thus the work of the United States Steel plant at Gary is ana lytic, in that it breaks the coal up into coke, gas and tar, each of which must then be handled separately.
The next operation is to unite the coke, ore and lime stone, which must be received separately and united in the blast furnaces. It is then analytic again, in that it separates the iron from the slag, which is sub sequently manufactured into cement ; and finally it is continuous, in that the iron continues without further additions until it emerges as bars.
6. Analytic manufacture.—The analytic type of manufacture is one in which the main material is gradually dissected to form many products, one of which is, however, usually of predominating impor tance. The best illustration is the meat industry, where the carcass is broken up into beef, hides, bones, etc., each of which is treated separately after it leaves the main stream. The important point in such industries is to provide means of taking away the parts that are removed, so they will not collect and block the main stream of work.
7. Continuous manufacture.—In the continuous manufactures the mass remains the same thruout the process, being merely acted upon and changed in form. This is by far the simplest kind and might be compared to a canal where the entire bulk of the water enters at one end and leaves at the other. In weav ing, the thread enters at one end of the loom, and after the application of labor alone, emerges as cloth at the other. In milling, the wheat enters at one end and the flour emerges at the other.
8. Assembling manufacture.—By means of the
assembling process many different materials are re ceived, worked upon and gradually brought together to make the finished whole. Building is the best illus tration because it is exclusively an assembling oper ation. It assembles the bricks, cement, plumbing and other manufactured products into a house. The im portant thing in assembling is to see that the neces sary parts come together at the right time and place, for all subsequent movement must wait until all the parts arrive.
9. Passageways must be provided.—VVhatever the type of manufacture, sufficient room must be allowed to provide convenient access to all parts of a machine, and to allow for the removal of any machine whenever necessary. Sufficient area must exist for the storing of as large a supply of working material and finished material as may be necessary, without interfering with the passageways. Storage facilities must be provided at each point where the flow of work is likely to be interrupted and wherever two streams unite. In order to minimize this area, the most economical method of stocking should be determined and the space should be allotted accordingly.
10. Transportation.—Adequate transportation fa cilities must be provided.
The open areas must be wide enough to permit the passage of two trucks in the aisles and for the sidetracking of trucks around machines. A truck system involving the retention of the material in the trucks, with as little unloading as possi ble, is an important feature and one deserving attention in an establishment. It involves the building of a considerable number of trucks, and departmental supervision, but is likely to result in economy. In some instances trucks are desirable, built so as to pick up and deliver a sheet-steel keg for hold ing work in progress. An ample supply of metal "tote boxes" for holding small parts will facilitate stock-moving and lessen losses of small parts.' Derricks, traveling cranes and industrial railroads are a great convenience in the handling of heavy ma terials and are often a necessity. Belt, link, gravity and pipe lines are serviceable where the material is uniform or will flow. Where the plant consists of several buildings it is customary to connect them by a system of tunnels radiating from the Tower house. These tunnels have cement floors, and brick and ce ment walls, waterproofed with asphalt. They are large enough to accommodate the trucks used and to allow a man to stand upright. They usually carry the electric and water pipes but no drainage.