Post by spurley on Nov 12, 2006 20:54:18 GMT
I would have thought that air coming into a grate through a hole in the fire would tend to cool that area? This might be true should the ashpan become too full and the contents begin to burn against the underside of the fire also, hence your blacksmith's forge analogy?
My experience of full sized locomotives and grate/fire problems were only fireman induced inasmuch as if they'd allow an area of clinker to develop which would concentrate heat onto fire bars and cause the impurities and firebars to fuse into one lump. This was mainly caused through impurities in the coal such as fools gold etc which would melt around the bars, a way we found to avoid such problems from 'duff' batches of coal was to 'beach' the grate. This process was as simple as shovelling three or four good shovels of pebbles into the fire bed when making up a fire prior to leaving the shed. This would have the effect of breaking up the lumps of clinker and maintaining airflow.
Cheers
Brian
My experience of full sized locomotives and grate/fire problems were only fireman induced inasmuch as if they'd allow an area of clinker to develop which would concentrate heat onto fire bars and cause the impurities and firebars to fuse into one lump. This was mainly caused through impurities in the coal such as fools gold etc which would melt around the bars, a way we found to avoid such problems from 'duff' batches of coal was to 'beach' the grate. This process was as simple as shovelling three or four good shovels of pebbles into the fire bed when making up a fire prior to leaving the shed. This would have the effect of breaking up the lumps of clinker and maintaining airflow.
Cheers
Brian
