The following text may have been generated by Optical Character Recognition, with varying degrees of accuracy. Reader beware!

THE MARINE RECORD. _ TESTING STEEL FOR SHIPBUILDING. ie (By JOSEPH R. OLDHAM, N. A.) ‘I think the time has arrived for those in any great and direct way responsible for the construction of our steel steamers, to take early action, as may seem to “them good, to rouse the producers of the material of which lake steamers are mainly constructed, to a sense of their responsibility, as it is more than evident to one who has watched the construction of large steel lake steamers in all of the old steel shipyards on these lakes, since steel came commonly into use, that much of our steel is not what it ought to be. Having had several ‘steel steamers to superintend during their construction for the last two or three years, it may be of use if I cite some experience I gained in connection with one of them. The steel of which the steamer is constructed was not cheap steel, nor was it manufactured at a small works; on the contrary, it was purposely purchased from one of the most reputable firms. Tests were reg- ularly applied, which were about as follows: Phospho- rus, 0281; dimensions, original, 1,992x2,201; dimensions after fracture, 1,662x100; area, original, 043,779 ; area, after fracture, .1662 ; elastic limit, actual, 13,408 pounds ; maximum load, actual, 2,529 pounds; elongation in eight inches, 2.161 ; elastic limit per square inch, 30,618; ples selected by them from every charge or cast em- ployed in the manufacture of the material, and these samples, when marked by them for testing, shotld be followed by the surveyor through the different stages of preparation until the tests are completed. Should the samples selected by the surveyor not fulfill the test requirements, the plates or angles from which they were cut are to be rejected, and further tests are to be made before any material from the same charge can be accepted. “‘When a surveyor is not in constant attendance at the steel works for the purpose of seeing the material tested, the association will require that tensile, and temper, and cold bend tests shall be applied either at the steel works or at the shipyard, to not less than one plate, angle bar, or bulb plate in every batch of fifty ora less number. Should the samples tested not fulfill the test requirements the whole of the material from that charge is to be rejected, and further tests are to be ap- plied toa sample from each of the other charges of which the batch is composed. In the event of any of these samples also failing, the whole of the material from the same charge or charges is to be rejected as in the first instance. “The steel used for rivets is to be of especial quality, produced if we are not to retrogade to all iron or wood ships again. More careful annealing of steel whch been locally heated may make such steel more reliable but only a change of the material requiring to be furnaced can secure us proper, that is, reasonable curity. If the foregoing is a system which may bri about partial, though only partial security, I may s that as yet we have very litile security ; for we have m such system. SS A LAKE BUILT TUG FOR NEW ORLEANS. (Illustrated.) x Through the courtesy of Zhe Engineer, New York wi are enabled to present to our readers an engraving of the powerful and handsome tug W. G. Wilmot recently launched from the yards of F, W. Wheeler & Co., West — Bay City, Mich., for service at New Orleans, La. The boat is named after her owner, is of steel throughont, and of the following dimentions: Length over all 110 — feet 6 inches; beam 23 feet; extreme draught 11 feet; the engines are triple expansion, with cylinders 16// 24 40’ by 28’ and drive a screw 9 feet 3” by 12 feet. The h. p. cylinder has a piston valve; the other two cylin- — ders have slides, worked by link motion, which is han- dled by steam reversing gear. ‘The boiler is of the Scotch type, 12 feet 6 inches diam- TUG “Ww. tensile strength per square inch, 57,796. per cent. of elongation in eight inches 27.02; per cent, of reduction of area, , The character of the fracture was silky. Now, if ever a shipbuilder might take credit to him- self for doing his best to have his steamer constructed of reliable materials, the man I refer to was that man ; but as to the result: One plate was fitted in place and cracked after being so fitted; this was removed and a better plate was ordered; it came, was fitted in place with the same result ; another and another, and yet an- other plate were ordered sent to. this yard, and were worked in with the same lamentable result. These plates were not of the same form, nor were they worked into the same part of the vessel; there was no fault 4 with the handling of the plates, for they stood working , and fitting together like the boilers of the Czar’s yacht; 4 but when we had all gone to sleep they cracked. Now, t the shipbuilder was hardly at fault in this instance; he 7 lost time and money over these plates. Perhaps the constructor was not at fault in connection with any re- cent great disaster. Let me quote an authority as a possible remedy for an intolerable state of things. “The steel will be required to withstand the whole of the following test, to be applied at the steel works under the personal inspection of the society’s surveyor, to sam- aS Cc. WILMOT,*? BUILT BY F. W. WHEELER & CO. soft and ductile, and samples of the rivets should be tested by being bent both hot and cold, by fastening down the heads, and by occasional forge tests, in order to satisfy the surveyors of their thorough efficiency. “Strips cut lengthwise or crosswise of the plate, and also angle and bulb steel must have an ultimate tensile strength of not less than 30 and not exceeding 35 tons per square inch of section, with an enlongation equal to at least 16 per cent. on a length of eight inches before fracture. Steel plates intended for flanged garboard strakes, if specially marked for identification, may be tested to within the minimum limit allowed for boiler plates, viz: 29 tons tensile strength per square inch. Steel angles intended for the framing of vessels and bulb steel for beams may have a maximum tensile strength of 37 tons per square inch of section, provided they be capable of standing the bending tests, and of being sufficiently welded. Strips cut from the plate, angle, or bulb steel are to be heated to a low cherry-red and cooled in water at 82° Fahrenheit and must stand bending double round a curve of which the diameter is not more than three times the thickness of the plates tested. In addition to this samples of plates and bars should be subjected to cold bending tests at the discre- tion of the surveyors.” The problem must be faced. Reliable steel must be eter by 12 feet 8 inches long, with three furnaces, 40 inches diameter by 8 feet long; the grate area is 63 square feet ; heating surface, 2,000 square feet. A fe-ed water heater is also furnished in addition to other fix- tures. ‘The Wilmot has steam-steering gear, and a com- plete electrical outfit, including search light. On her trial trip, in Saginaw Bay, the W. G. Wilmot, made 16 miles per hour under partial power, developing 700 h. p. on 160 pounds of steam, and 125 revs. per minute. This and other contracts for moderate sized vessels is suffic- ient evidence that the ship building industry on the lakes is only limited by the size of the St. Lawrence system of canals. Even the most sanguine must admit that the system of sending tonnage to the seaboard in sections is not an _ economical one, although it has been successfully ac- — complished in the case of the large freight steamers Mackinaw and Keweenaw, also built by F. W. Wheeler & Co., yet, such contracts can only be placed at lake shipyards under special circumstances. Where the to: nage can proceed in due course and without extra ex- pense being incurred there can be little doubt but that lake shipbuilders now can figure at as close a margin any shipyard on the coast and from past experience cal produce equally satisfactory tonnage in wood or sail or steam. ‘ \