Boulogne-Billancourt Cedex, France-based Vallourec SA plans to acquire four business units from Grant Prideco Inc., Houston, (NYSE: GRP) for US$800 million. The units are within Grant Prideco's tubular technologies and services segment and include Atlas Bradford Premium Threading & Services, TCA and Tube-Alloy. The businesses will be added to Vallourec's seamless tubes unit that focuses primarily on the energy industry. The XL Systems unit will be excluded from the sale.