Cellulosic Electrodes
In the AWS E 6010 and E 6011 series of electrodes, the protective covering is composed of cellulose (C6H10O5) and silicate binders. The cellulose decomposes in arc accordings to the following equation:
(C6 H10 O5 + 0.5 O2 = 6 C+ 5 H2)
Cel lulose + Oxygen = Carbon Monoxide + Hydrogen.
The products of this reaction, carbon monoxide and hydrogen represent a total of 400 times increase in the volume of gas generated over the volumes of the unburnt coating. These gases rush outward from the arc and push the atmosphere away from the puddle. The gas produced raises arc voltage and thereby increases the amount of heat produced from the electricity in the arc. The cellulose electrode has therefore, a very hot arc even at lower current value and this together with the gases evolved from the coating at high pressure give rise to a "digging" arc and deep penetration. Naturally there is very little slag formed, and this makes welding possible in all positions.
This electrode is extremely good for pipe welding. The weld metal is of good quality. It generally meets with high pressure tests & X - ray tests very easily. This electrode requires a slightly longer arc for complete burning of the cellulose in the flux coating.