National Oilwell Varco designs, manufactures and sales equipment and components used in oil and gas drilling and production, the provision of oilfield inspection and other services and supply chain integration services. The company s integration services serve the upstream oil and gas industry. It offers a range of equipment, systems and components for land rigs and semi-submersible rigs worldwide. Located in Houston, National Oilwell Varco has provided oilfield products and services for more than 140 years.