pipe vs pipe up

pipe is a noun but pipe up is not a noun.

Word	Noun	Adjective	Verb	Adverb
pipe	Yes	No	Yes	No
pipe up	No	No	Yes	No

As verbs, pipe and pipe up are synonyms defined as:

Other synonyms of pipe include shriek, shrill.

pipe (noun)	pipe up (noun)
a long tube made of metal or plastic that is used to carry water or oil or gas etc.
a tube with a small bowl at one end; used for smoking tobacco
the flues and stops on a pipe organ
a tubular wind instrument
a hollow cylindrical shape