July, 1905.] 



KNOWLEDGE & SCIENTIFIC NEWS. 



145 



A New Process for 

 Welding Aluminium. 



The Cowper-Coles process for welding aluminium re- 

 quires no flux, and does not necessitate the hammering 

 of the joint when in the semi-fluid state. The process 

 is especially suitable for wire rods and tubes and other 

 drawn or rolled sections, and consists in placing the 

 parts to be welded, after being faced off square, in a 

 machine (illustration No. i), fitted with clamping 



Cowper-Colcs's Machine for Welding Aluminium. 



.-1, Serten; B. Aluminium Bo els ; C, Lamp; D, Levers for applying prcsiuve : 

 E, Pump; Fj Water Remivoir. 



screws, which are capable of moving horizontally on 

 guides; the movement of the clamping sciews is con- 

 trolled by the levers D. The aluminium to be welded 

 is heated by means of an ordinary benzine lamp. As 

 soon as the rods have arrived at the necessary tempera- 

 ture, slight pressure is applied to the levers D, which 

 causes the aluminium rods to unite, and a ring of metal 

 is squeezed out, as shown in illustration No. 2. This 



Joint after Welding. 



ring is largelv composed of aluminium oxide, and acts 

 as an insulating and supporting collar, the molten metal 

 being retained within this collar. The weld is then 

 instantaneously quenched by turning a handle attached 

 to the screen A, which allows water, under pressure, 



to be projected on to the joint from the reservoir F. 

 The same handle which turns the water on, places the 

 screen A in front of the heating flame. The water 

 pressure is maintained by air supplied by the hand 

 pump E. The rod is finally removed from the machine 

 and the collar filed off, when it will be found that the 

 joint is as strong as the rest of the metal. An oxygen- 

 hydrogen flame or ordinary gas with or without air can 

 be substituted for the benzine lamp. The process is a 

 simple one, and can be worked by any unskilled work- 

 man. 



Illustration No. 3 clearly shows the molten aluminium 

 supported by a pipe or case of aluminium oxide, 

 the case havincr been pricked with a steel point 

 to allow some of the molten metal to flow out. 



The following table gives the result of tests for 

 tensile strength on twelve consecutive welds (not 

 picked specimens) made by the process just 

 described. The fractures occurred at a con- 



siderable distance from the weld, showing that the 

 metal has not deteriorated at the weld. In the twelve 

 tests referred to, not one specimen broke through the 

 welded portion. 



