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the channel side tank is 10 per cent stronger than the present side tank of plate construction. In connection with the strength analysis, a careful check has _ been made of the weights involved in the two designs, and the riveting in each. The structures considered in each case were made up of parts as follows: 1. Plate side tanks; plating, frames, bounding angles, side tank and outer shell stringer plates, transverse chan- nel braces, and bulkheads spaced 72 feet. 2. Plate tank top; plating, seam and butt straps, tank top angle stiff- eners, center keelson top angles, tank top angle clips, tank top corner angle bars, and watertight floors spaced 72 feet. 3. Channel side tanks; side tank channels, brackets, transverse chan- nel braces, side tank and outer shell stringers, bounding angles and bulk- heads spaced 72 feet. 4. Channel tank top; tank top channels, extra height of center keel- son 38% inches, channel web butt straps, flange angle clips, interme- diate floors with brackets, tank top corner angle bars, and the watertight floors spaced 72 feet. A summary of the results obtained follows: Weight, Material and Rivet Heads of two Side Tanks. Hold Length 438 Feet. Plate construction Channel design 233.69 net tons 241.06 net tons Weight, Material and Rivet Heads of Tank Top. Hold Length 438 Feet. Plate construction Channel design 832.47 net tons 338.00 net tons Riveting in two Side Tanks. 438 Feet of Hold Length Plate construction Countersunk Non-Countersunk 41,026 8,176 Total 49,202 8314 per cent of total require countersinking. Channel Construction Countersunk Non-Countersunk 13,942 49,640 Total 63,582 22 per cent of total require countersinking. Riveting in Tank Top. 438 Feet of Hold Length Plate construction Countersunk Non-Countersunk 67,489 14,417 Total 81,906 82 per cent of total require countersinking Channel Construction Countersunk Non-Countersunk 10,420 68,036 Total 78,456 18 per cent of total require countersinking From the foregoing data, we find that in a complete channel tank top and side tank construction, the fol- lowing advantages are obtained over the plate construction: 1. An increase of 50 per cent in tank top strength, and 10 per cent in side tank strength. 2. Elimination of 84 per cent of the countersinking in the tank tops, and 61 per cent in the side tanks. This reduces in like proportion, the number of rivets which penetrate the hoppers, and which is one of the dis- tinct advantages in the channel con- struction. 3. Elimination of 51 per cent of the present tank top calking, and 49 per cent of the present side tank calk- ing. 4. Elimination of 60 per cent of the tank top butts, (72 feet channel lengths against 30 feet length plates). There are no butts in the channel side tanks. 5. Elimination of the fabricating and erection costs of all plate side tank frames. There are no_ side tank frames in the channel construc- tion. 6. Elimination of about 60 per cent of the present bolting up costs, if the channel flanges are set up with a bull machine. 7. A complete elimination of the cost of planing the edges to tank top plates. 8. A considerable saving in erec- out the floors to take the flanges, as is done in the plate design to allow the fore and aft tank top angles to pass through. 11. The complete channel design weighs 12.9 net tons more than the plate construction in the 438-foot hold length vessel for tank tops and side tanks. In fact no effort has been made to reduce the weight of the channel design, as the additional strength ob- tained by its use, is needed to meet clam shell abuse. Any additional dead- weight capacity which might be gained through a reduction in weight in the hoppers of a lake ship, would mean extra expense in repairs. It is the tank tops and side tanks, which take the hardest usage in our lake ships. 12. The channel tank top has only half the amount of unsupported tank BACK OF NEWLY ERECTED CHANNEL STEEL BULKHEAD ON THE STEAMER JAMES J. HILL OF THE PITTSBURGH STEAMSHIP CO. SHOWING HORIZONTAL CHANNEL STIFFENER AND CHANNEL BRACING TO TANK tion costs should be effected, as the channels can be set up in large sec- tions, rather than having to set up each plate separately. 9. Drilling or punching the flanges to any desired pitch, as it is all uni- form work, can be done quickly, and so can the riveting. The actual cost of riveting compared with the plate construction should be less, in view of the fact that the most of the rivets, can be bull riveted, the little bolt- ing up required, and the far less number required to be countersunk. 10. By the flanges of the tank top channels being brought to bear upon the top flanges of the floors, some of the direct shear on the flange rivets is relieved, and a further saving is effected by not having to cut MARINE REVIEW—June, 1927 TOP top area, and the side tanks only one third of the unsupported area, as com- pared with the plate construction, which will increase the buckling re- sistance and reduce the scalloping in the hopper shell. One of the main purposes in the channel construction is to throw as much of the weight and strength into the hopper shell as possible, to take abuse, and back it up with sufficient stiffening to make it stand up. In other words, additional weight is introduced where it is need- ed, without serious decrease in dead- weight. Net income of Bush Terminal Co., and subsidiaries for the quarter ended March 31, 1927, was $450,080 after interest, depreciation, taxes, etc. 33