Traiisnrlions Society Naval Architects and Marine Emiineers, Vol. 36, 1918. 



Plate J 33. 



To illustrate f>aper on "The Application of Electric VVcldiny to Ship Construction," 



by II . Jasper Cox, Esq., Member. 



.KIMO OF WELD . 



TACK 



STMBOL ' 



A TACK weld is applying the welding mat- 

 arlal In snail aeotlons to hold two edg«s to- 

 gether, and ahould always be speoified by glvlnfe- 

 the SPACE from oenter to oentor of weld and the 

 LEHSPH of the weld Itself. No partloular 

 "Desiga of weld" is necessary of oonslderation. 

 X TAOK is alao used for temporarily hold- 

 ing material in place that is to be solid- 

 ly welded, until the proper aligsmusnt and 

 eltloa is obtained, and in tMs case, neither 

 the I^HTH, SPACS, or DESIGH OF VELD are to be 

 speoified. 



CAULKING 



SYMaOL-7* 



A OiULEIKC weld Is one la wfcloh the density 

 of the osystalin© metalj used to close tip the 

 seam or opening, is such, that no possible 

 leakage is visible ■oiaier a water, oil or air 

 pressure of 25 lbs, per square Inoh. The ulti- 

 mate atrength of a c^uUiing tyeld is not of mat- 

 erial iia^rtance,- neithar is the "Design of 

 weld" of this kind neoeasary of ooasidoration. 



The operator most be the judge In the number 

 of layers needed for a tight weld, although the 

 designer should specify a mininnm amount of 

 lavers. 



STRENGTH 



SYMBOU" 



A STISEOTH weld is one in whi<fli the ssc- 

 tioaal area of the welding material niuat be 30 

 considsred that its tensile strength a^id el-s 

 OEgatlon per square inoh niist be e^^ual at least 

 80% of the ultimate strength per square inch of 

 the surrounding matsriale (To be datcrialned 

 aad speoified by the designer j« The welding 

 material can be applied in any number of layers 

 I beyond a mininKmj speoified by the designer. 



Tlie denaity of the orystaline motals is 

 SOT of vital importaaoee In this form of v;eld9 

 the "Design of weld" asost be specified by 

 the designer and followed by the operator. 



COMPOSITE 



aYM»©i.-S' 



A COMPOSITE weld is one in vyhich both the 

 strength and density are of the BXist vital im- 

 portance. The STRSHO-TH must be at least as 

 specified for a "strength weld", aai tho 

 density must moot the rsciUirsaocta of a 

 "Gaulklng weld" both as abovo i'bfined. The 

 minlmam number of layers of v^alding ti'iatorial 

 nMst always be specified by the designer, but 

 the welder mast be in a position to ta:ow 

 If this number mast be increased acooKling 

 the welders woi^cing conditions. 



THE NORRIS PETEKS CO., WASH. D. C. 



