Kirby Corporation has signed an agreement to purchase United Holdings for $270m, including a three-year earnout provision for an additional payment of up to $50m payable in 2014.

United Holdings manufactures oilfield service equipment including hydraulic fracturing equipment, with major customers in oilfield service companies, oil and gas operators and producers, compression service companies and transportation companies.

The acquisition is expected to take place in April 2011 with finance from Kirby’s existing cash and revolving credit facility.

Kirby CEO Joe Pyne said that assuming the acquisition closes in April 2011, anticipated revenues from United’s operations will be in the range of $285m to $335m.