Northwest Pipe Company is the largest manufacturer of engineered steel pipe water systems in North America. With our strategically located Water Transmission manufacturing facilities, including two PermalokÂŽ facilities, we are positioned to meet North America's growing needs for water and wastewater infrastructure. We supply large-diameter, high pressure pipes, manufactured through a double-submerged arc weld process, in diameters ranging from 18-inches to 156-inches. Projects are engineered to customer requirements and include a wide variety of internal pipe linings, external coatings, and custom fabricated fittings. Two of the Water Transmission facilities manufacture the proprietary PermalokÂŽ interlocking pipe joining system that takes the field butt welding out of joining steel casing pipe. The Company is headquartered in Vancouver, Washington and has manufacturing facilities across the United States.
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