TO SHIP CONSTRUCTION. 



205 



Workmanship and Finish. — (a) Electric welding wire shall be of the quality and 

 finish known as "Bright Hard" or "Soft Finish." "Black Annealed" or "Bright 

 Annealed" wire shall not be supplied, (b) The surface shall be free from oil or 

 grease. 



Tests. — The commercial weldability of these electrodes shall be determined by 

 means of tests by an experienced operator, who shall demonstrate that the wire flows 

 smoothly and evenly through the arc without any detrimental phenomena. 



Further reference emphasizing the importance of this factor will be found later 

 under the Rules of Lloyd's Register of Shipping. 



3. The chemical composition of the material to be welded is a quantity over which 

 we have no great control, but open hearth mild steel of the quality under considera- 

 tion has usually sufficient uniformity in its chemical composition to permit a general 

 application of the foregoing specification. 



However, the effects of varying carbon and other contents, including occluded 

 gases, are being carefully investigated with a view to obtaining a more complete 

 knowledge, and it is considered that a true understanding of the successful arc weld 

 will result only from a combination of metallurgical and electrical study. 



4. The size of the electrode in relation to the current strength and the thickness 

 of material to be joined is also a matter of obvious importance. 



While it has not yet been thought expedient to standardize these relations, the 

 following table published by the Quasi Arc Weltrode Company may be found of in- 

 terest : — 



Electrodes and Current Required for Sheet and Plate Welding. 



Thickness 

 of work 



16 8. W. G... 

 14 8. W. G... 

 12 S. W. G... 

 10 8. W. G... 

 3/16" plate . . , 

 1/-1" plate . . . . 

 6/16" and 3/8" 



1/2" plate. ... 



5/8" and 3/4" 



Preparation of joint 



Close joint 



Close joint 



Close joint 



Close joint 



1/16" open 



Veed half-way through and 1/32" open . 



Veed right through to 70° and 1/16" open 

 Two runs are necessary — 



First run 



Second run 



Veed right through to 60° and 1/8" open. 

 Two runs are necessary — 



First run 



Second run 



Veed right through to 60° and 1/8" open. 

 Three runs are necessary — 



First run 



Second run 



Third run 



Size of 

 electrode 



Inches 



0.08 

 .105 

 .105 

 .135 

 .135 

 .16 



.135 

 .16 



.135 

 .192 



.135 



.16 



.16 



Current in 

 amperes 



20 to 25 



30 to 35 



40 to 45 



50 to 65 



75 to 95 



93 to 110 



75 to 85 

 93 to 110 



75 to 85 

 100 to 120 



75 to 85 



95 to 110 



100 to 120 



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