CPC Subgroup
F22D 1/40 Combinations of exhaust-steam and smoke-gas preheaters
Full Title
Feed-water heaters, i.e. economisers or like preheaters > Combinations of exhaust-steam and smoke-gas preheaters
F22D 1/40 Feed-water heaters, i.e. economisers or like preheaters > Combinations of exhaust-steam and smoke-gas preheaters