TO SHIP CONSTRUCTION. 



209 



The figures have been adjusted to suit the present cost of welding labor and 

 electrode material in this country, which differ considerably from those obtain- 

 ing in England: — 



Metal Electrode Arc Welding (Quasi Arc). 



Other figures prepared by the Welding Committee show the possible cost of a 

 fillet weld on a J^-inch plate, using a motor generator set and bare electrodes, to be 

 as follows: — 



Average speed of welding on continuous straightaway work 5 ft. per hour 



Amount of metal deposited per running foot 0.6 lb. 



Current 150 amps, at 20 volts = 3 kilowatts. 



Motor generator eff. 50% = 6 KW H- 5 equals 1.2 K.W.H. per i ft. run 



1.2 K.W.H. at 3 cents per K.W.H. equals 3.6c per ft. 



Cost of electrode 10 cents per lb. and allowing for waste 



ends, etc., equals 7.2c per ft. 



Labor at 65 cents per hour equals 13.00 per ft. 



23.8 per ft. 



The curves plotted in Plate 139 are the results of data collected by the Quasi 

 Arc Weltrode Company, and show the lineal feet per hour of straight line flat weld- 

 ing for different thicknesses of plates tog^ether with percentage corrections for ver- 

 tical and overhead welds. These results were obtained under laboratory conditions, 

 however, and for bulk work in the field or shop it might be advisable to reduce them 

 by a considerable margin, even as much as 50 per cent. 



The protection of the worker on ship work in the field is one which will require 

 careful study. The welder himself must be provided with a hand glass or mask 

 which, while adequately protecting his eyes and body from the arc and falling metal, 

 will not impair his movements while working on high stagings in all weathers. 

 Arrangements should also be made to protect his neighbors or other workers from 

 exposure to the arc. 



