Public funds to cover work with carbon plumbing components (9)

'plumbing components' is the definition.
The answer and definition can be both man-made objects as well as being plural nouns.
Maybe you can see an association between them that I don't see?

'public funds to cover work with carbon' is the wordplay.
I cannot really understand how this works, but
'to' is within the answer.
'carbon' could be 'c' (chemical symbol) and 'c' is located in the answer.
This explanation may well be incorrect...

Can you help me to learn more?