I recently read an article about all of these oil and gas
pipelines that are either building now or scheduled to be
built in the next few years. Which companies, outside of
the steel companies etc. are the main builders of this
What are you asking? The MLPs are the owners and they contract out the pipeline building and materials. Lots of contracters, pipe and valve companies, surveyors involved. Companies like Flowserve have already moved a bunch. Am sure there are contracters getting rich out there too!