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units that are to deliver highly su- perheated steam alloy tubes are joined to carbon steel tubes by this process, with the high-temperature- resisting alloy material in the hot- test zones. This welding together of dissimilar metals is an example of how the art as practiced in this shop has gone considerably beyond the welding of boiler-plate steel. Furthermore, chrome-nickel alloys of various analyses, as well as chro- mium-clad steel, nickel-clad steel, and other materials, have been suc- eessfully welded, The trend towards the use of high steam temperatures and high fur- nace temperatures, especially in land boilers, has given impetus to the study of welding alloys such as those mentioned, and has also led to the wider use of alloy castings for serv- ice at high temperatures. This is a matter that is relatively unimpor- tant as it now applies to marine service, but the steadily mounting temperature of steam used in ma- rine propulsion presages a wider use of alloy materials in the future. It is, therefore, appropriate for us to spend a few moments in the alloy foundry while on our trip through this plant. The alloy foundry is interesting, not only because its products may soon be important parts of the ma- rine boiler of the near future, but because it furnishes such an apt illustration of the tremendous change that has taken place during the past decade or two in the art of boiler making and in the equipment found in a modern boilershop. This de- partment, in fact, has little resem- blance to the popular conception of a foundry. All heats are taken from high-frequency electric-induc- tion furnaces supplied with energy from one 150 kilowatts, 2040-cycle generator and one 1250 kilowatts. 960-cycle generator installed in a room that resembles, in general ap- pearance, an up-to-date substation 12 of a modern public-utility system, There are nine melting furnaces, ranging in capacity from 100 to 3600 pounds. The alloy foundry is also equipped with testing apparatus for checking and controlling the quality of the sand used in the molds; auto- matically-regulated core-baking ov- ens, hydraulic testing equipment cap- able of exerting pressures up to 6000 pounds per square inch, and a centrifugal pipecasting machine that can produce cylinders up to 11 inches in diameter and 10 feet long. The diversity of the work done in a modern boilershop is further illus- trated by such products of the shop under consideration as_ forgings weighing 3500 pounds each and oil- ® Side view of 2600-ton twin press used in forming heavi- er drum plates for boilers and pressure vessels ® + A battery of vertical boring AVUUS: Us * CLE, forge shop at the plant of the Babcock & Wil- COu: Cos For machining lrum. heads and manhole covers burner sprayer plates weighing but a fraction of an ounce each and hav- ing machined tolerances of a nature so close as to have been practicaily unknown in the art as practiced only a comparatively few years ago in boiler’ plants. In the forge shop of this establishment, noz- zles ranging in size from the smallest in general use to thuse 24 inches in diameter are made, and drum heads as large in diameter as 60 inches are flanged and dished by specially designed hydraulic machin- MARINE REVIEW—July, 1934 ery. In contrast to this operation, the sprayer plates of oil burners are drilled and milled to plus or minus 0.0005-inch and handhole plates and handholes are machined to similarly close tolerances. The visitor to this plant, there- fore, views in succession work of the heaviest kind being done in the forge shop, and work of a most pre- cise nature being performed in an- other department. Another’ con- trast in the nature of work per- formed is that which exists between those parts made especially for each boiler and other parts that are high- ly standardized. Thus one sees, on the one hand, a drum being fabri- cated as a separate and individual part for a specific boiler and, on the other hand, stoker links, water- wall blocks, inspection doors, and many other parts being produced on a quantity basis by the latest mass-production methods, The fabrication of casings is one operation of the business that is Special, in the sense that each cas- ing is made for a specific boiler but is standardized to the extent that certain operations are performed on machines either built for, or ad- justed to, the work to be done, and certain standard-size panels are made which, with other special sizes, are assembled to comprise a complete easing of special overall dimensions and shape. Perhaps the most important con- sideration in the production of cas- ings is that of air tightness, espe- cially for boilers that are to be op- erated with forced draft. The ini- tial steps in the fabrication of an air-tight casing consists of shear- ing the sheets to size, followed by removal of the corners by coping. The plates are then put in a bend- ing brake and flanged, after which the flanges are welded together at the corners. The joining of the flanges by welding, combined with accuracy in bending and forming, (Continucd on Page 40)