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The bracket plate A' is 3% thick and has an area of 148 square in. and equal to 384.8 tons tensile strength. Example: Bracket plate D E 52% xX ¥%. Io. X .13/16 rivet holes: equals. 13 inches. - 521%, in. -- 13 in. = 39.5 in. 39.5 X 3% X 26 = 384.8 tons. The. ange has the same material so that it is safe to punch the 16 holes in the bracket plate and angle. The 16 rivet holes where the bracket plate laps onto the channel shows that there are no more in a.lne than 3 holes which does not cripple the chan- nel' or reduce its strength to less than 154 tons. This example shows that the mate- rial and rivets correspond and if car- r.ed out as per sketch it will 'come as near as practicable to the. punched material. The web frame must be taken into considerat'on in this connection. 16. rivet holes have been punched across the plate reducing the material from 66, to.53. inches. Between the stringers shown by Fig. 2, lightening holes are cut out 20 in. wide so that it reduces the metal in the plate to 46 inches instead of 53. At the top of the web. frame the connect'on to the stringer is made. with double angles and 11 34-in. diameter rivets giving a double shear, and hav- ing a value each of 21 tons per rivet. 2). 11 = 231. tons; for connection at top. The connection at the bottom is made by double lappi ne: the plate at line of tank top. The lap rivets amount to 26 in num- ber and equals 26 X 12 = 312 tons. This investigation shows that the connection to the main deck stringers is the weakest part of the web plate and may be summed up as follows: Web plate through I'ne of holes at ' stringer, 33 in. X % in' X 26 = 520 tons. Through lightening hole 46 in. X 3 in. X 26 = 449 tons. Bottom at girder, 315 tons. Bottom lap, 26 rivets X 12 = 312 tons. Top of stringer, 11 rivets X 21 = 231 tons. This' investigation. does not consider the face angle at the middle of the web plate and goes to show that the Ine of rivet holes for the side stringer ds the strongest part of the wep frame. Th's example will show. how inftri- Cate it is to get all the materials to. agree in area of section. When there is a large surplus of ma- terial it is reduced by punching out TAE Marine Review holes as shown in bracket-A, Fig. 20, and the webs Fig. 2, By reducing the weight adds to the total amount of tonnage a vessel car- res in the season, care of course must be taken that no part of-the vessel be reduced in strength below. the unavoidable .weakest section, % Fig. 21 shows the main ia str: ing-, er whith 15.51) in; 22 9/1 ci "thick There are eight rivets rhrodehe D Ba connecting the stringer to the. beam and channel B. so "that 8 x 15/16 in, = 75g 5k / 5 455 in, 435 in, 2 9/16. iio X26 Ga 22 tons tensile strength, 636. 22 ------ = 4241 rivets 7% in. diameter. 15 The rivets of the outer rows must not be wider in pitch than at the beam or bracket. The back rows in this butt lap have 8 rivets in each row and 27 rivets in the middle making four rows of rivets with a total of 43 rivets 7% in. diame- ter. 'The intercostal plate only contri- butes. four. rivets 34 in. diameter to' the - strength when the. stringer is under tension G H, Bic 2i The material in the frame. space M N is equal to 51--1 rivet hole =: 50 in. 49 in. X 9/16 in. X 28 = 787.36 tensile strength. 15/16 in. diameter ne may be taken as 1 inch because the one side of the hole is: larger, and is practi- . cally 1 inch diameter. Fon all - practical purposes yj-in: and 7%-in. diameter _ holes' may be -taken- as..1 inch. ce This stringer having no passing strakes to ass'st it, must have a cate- ful riveted butt connection as shown _ py A; big 21. There is no saving by running the stringer plate to the shell because the value of the plate ends at the inside of the channel F. The intercostal shown' by C is the most economical method of filling up. the space between the frames' which serves the purpose of stiffen: ng, ie shell ae ae the shell plating; thus saving" an i and the' rivets' through, same. late a. 128 be tee eo On face a He singe : "deSigning departments for 'hall and Re in. channel B is' run which contributes to the tensile strength of the. stringer plate when the channel. as. properly. strapped as 'shown by examples, Figs. 17: 18 abd 19 This example shows that ier are 5.6 square in. more area through line MN thee A Re De ee 8 > , boats. for dry, docking confining ate energy to. "special: he : "nage, such as yachts, passenger, tags, 419 being the weakest part of stringer and channel on face, the stringer be- tween frames. might be lightened up by cutting out Holes. across. the (stringer A -hole 12° in. plate . could be : punched » out'. (of. the plate | without in any way injur. ng the Stren ett of the see plate, 'The solid material in the inttercos- "dale does not, figure. Of valtie 'in, this. ' . example seeing', that" the rivets MG a é would shear if the stringer plate cwere. a break through line M N. ~The rivets N G H are equal to. ise 5 = 75 rons' "the Thtercostal equals 20 in. X He xX 26 = 195 tons. ? ae wide angles shown at K are for connecting the arch plate to the _ stringer. Double angles dre used on top of stringer and underside of same in order .to get as much strength as possible for the web frames. Ex- amples, in connection with Fig. 20 show that the weo frame' is weak- est at the stringer plate. In the case of Fig: 20, the plating of tank side assists the web but in this case the web upon itself. MANITOWOC DRY DOCK CO. The Manitowoc Dry Dock' Co.' has a very compact and economical plant -and in the meantime are very busy, employing 600 men steadily. Fifty vessels have been wintering in Manitowoc and some very large repairs have been done to quite a number of them. Seventy-four per cent of these vessels have more or less been in the hands of the Manito- woe Dry Dock Co. The plant is built on a point of land a where the river forms an S, and ex- tends so that there is water on two sides" of same, : This arrangement aoe i handy, as. al large number of vessels can be, laid "3 up. along the docks of the yard ante convenient. for repairs. In front of the yard are two large' 4 _ turning. basins, making the. shifting, of. machinery are seen. This company in the 'meantime dredges, lighters, etc. ; 'There is one building berth 710 ft. long and one 425 ft, the former is entirely depending |