UPDATE 1-NuStar Energy to offer 5 mln units, shares dip

* Net proceeds to fund acquisitions, capex and repay debt

* Shares fall 5 pct in post-market trade

Nov 9 (Reuters) - NuStar Energy LP (NS.N), which operates oil pipelines, storage facilities and asphalt refineries, said it will offer 5 million units and use the net proceeds to fund potential acquisitions and capital expenditures, and repay debt.

Shares of the company dropped 5 percent to $52.13 in trading after the bell. They closed at $54.94 Monday on the New York Stock Exchange.

NuStar joins an inflated list of energy firms that have chosen equity offerings as a means to raise funds to bolster their capital budget and expansion plans. The company said it has given its underwriters, Morgan Stanley & Co Inc, UBS Securities LLC, Credit Suisse Securities (USA) LLC and Wells Fargo Securities, a 30-day option to purchase up to 750,000 additional common units. (Reporting by Antonita Madonna Devotta in Bangalore; Editing by Anne Pallivathuckal)