Some pipes for Chanel holding service on empty bus (8)

'some pipes' is the definition.
Although both the answer and definition are plural nouns, I don't see how one could define the other.

'chanel holding service on empty bus' is the wordplay.
'chanel' becomes 'coco' (I've seen this in other clues).
'holding' indicates putting letters inside.
'service' becomes 'rn' (abbreviation for Royal Navy).
'on' says to put letters next to each other.
'empty' means to remove the middle letters.
'bus' with its centre taken out is 'bs'.
'coco' going around 'rn' is 'cornco'.
'cornco'+'bs'='CORNCOBS'

'for' is the link.

Can you help me to learn more?