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

1 around better job than formerly. The weight of the channel tank top is slightly greater than a plate top, put has approximately double the strength of the plate construction. In renewing tank tops on lake steamers, however, this item is negligible be- cause the retanking is always heavier than the original construction. In fabricating the sections in the hold of the vessel, ten ship channels were laid side by side, as shown in the upper left hand corner of the large illustration. They were squared and clamped together. When the sections were perfectly squared and clamped al si of 65 to 70 feet per hour were at- tained on toes of the sections. As the sections were finished, they were turned over and laid in place parallel to the keel. The flanges of the chan- nels were then welded to the floor by means of plate chips on alternate flanges. When the channel sections were tack welded in place, parallel to the keel, the automatic welder was again placed into position on the sections and the heels welded together. The accom- panying illustration shows the elec- tronic tornado automatic tractor weld- ing a seam. This machine utilizes the hs The advantages of the channel sys: tem of construction, fabricated by arc welding, over the traditional riveted plate construction is a stronger and more rigid tank top with practically no increase in weight, and a reduc- tion in construction costs. The addi- tional stiffness is obtained due to the flanges of the channels acting as con tinuous stiffeners, and because they are more closely spaced than the stiffeners in tank tops of the tradi- tional plate construction. For intermediate floors, the channel tank top only requires half the num- ber of stiffeners as in the plate tank UPPER LEFT—TACK WELDING SECTION OF CHANNELS BEFORE FINAL WELDING WITH AUTOMATIC CARBON ARC—UPPER RIGHT— MAKING TANK TOP IN ONE PIECE OF STEEL BY ELECTRIC WELDING CHANNELS. LOWER LEFT—SECTION OF WELDED CHAN- NEL SIDE TANK IN PLACE. LOWER RIGHT—SECTION OF WELDED CHANNEL TANK TOP—ALL VIEWS OF STEAMER C. 0. JENKINS they were tack welded together on the toe so as to hold them in place while being joined to each other by the electronic tornado process of auto- matic carbon are welding. By this process the metal in the heels and the toes of the flanges of adjacent chan- nels were fused into each other with- out the use of additional metal. Thus the entire tank top is literally one Solid Piece of rolled steel with the Joints as strong as the members they Join. In joining the channels, speeds carbon arc welding process and fuses the metals into each other as_ it travels along the seam. There were approximately 48,600 lineal feet of welding on the CHARLES O. JENKINS. This modern type of ship con- struction was designed by W. G. Bartenfeld, for the Jenkins Steam- ship Co., owner of the vessel. The Channel Steel Hull Corp. controls the American patents of W. G. Barten- feld for the channel system of con- struction. MARINE REVIEW—June, 1930 top because the flanges of the chan- nel tank top have enough strength to permit a wider floor spacing than can be obtained in a plate tank top. Maintenance costs are reduced and life of the tank top is increased due to elimination of rivets which often work loose and whose heads become badly worn due to abrasive action of buckets and cargo; also because this type of tank top has practically double the strength against buckling as that of the plate tank top. 37