I think that the cylinders would have been used for cutting . This was the - nearly 100% - use in REME workshops that I was part of. Mind you, some of the Civies could weld!
You would have been surprised at just how many Military - 50s to 60s - did not know about the DA Cylinders!!! Mind you - in my 12 plus years service - I never met anybody who could weld!!!!
I am on that photo somewhere!!!!I stood on one of the trucks lining the Parade ground! I ran out of film just as the Royal Landrover passed me just 6' away!!!