Clock Spring Company - Manufacturing, installation training, and field installation of fiberglass composite pipeline repair sleeves. These sleeves are approved as permanent repairs for both liquid and gas pipelines in the USA. International services from a home base in Houston, Texas, USA. T.D. Williamson, Inc. - International manufacturer and services provider for hot tapping, pipe cleaning, internal inspection and other pipeline maintenance equipment and services. Based in Tulsa, Oklahoma, USA with offices around the world. Shaw Pipeline Services - Specializes in technology-based exploration and production products and services for pipeline, petrochemical and industrial markets worldwide. Manufacturing and service facilities globally. Allan Edwards Companies - Manufacturer of concrete river weights, concrete pipeline coatings and steel repair sleeves for all pipelines. Consultancy for pipeline buoyancy calculations. Offers on-site custom concrete coating services. Based in Tulsa, Oklahoma, USA. Sovde Enterprises, Inc. - Natural gas pipeline contractor offering a broad variety of construction and maintenance services. Headquartered in Bemidji, Minnesota, USA. Mainline Integrity Services, Inc. - Pipeline integrity management, regulatory compliance and site remediation services for pipeline operators. Based in Houston, Texas, USA. JW's Pipeline Integrity Services - A consulting and field services company specializing in pipeline integrity services for underground pipelines. Includes classroom and onsite training seminars.