DIFF Subgroup
F22D 1/38 Constructional features of water and air preheating systems
Introduced: September 1968
Full Title
Full titles differ between systems:
IPC:
Feed-water heaters, e.g. preheaters > Water and air preheating systems > Constructional features of water and air preheating systems
CPC:
Feed-water heaters, i.e. economisers or like preheaters > Water and air preheating systems > Constructional features of water and air preheating systems
No child classifications to compare. This is a leaf node in both IPC and CPC.