riser pipeline vs riser pipe

riser pipeline and riser pipe both are nouns.

Word	Noun	Adjective	Verb	Adverb
riser pipeline	Yes	No	No	No
riser pipe	Yes	No	No	No

As nouns, riser pipeline and riser pipe are synonyms defined as:

Other synonyms of riser pipeline include riser, riser main.

riser pipeline (noun)	riser pipe (noun)
a vertical pipe in a building	a vertical pipe in a building