Steel Pipe Manufacturers
| Universal Stainless & Alloy (Titusville, PA) |
| Valmont Industries Inc (Elkhart, IN) |
| Walbridge Coatings Inc (Walbridge, OH) |
| Westinghouse Electric Co (Pittsburgh, PA) |
| Wheeling-Pittsburgh Steel Corp (Yorkville, OH) |
| Woodings Industrial Corp (Mars, PA) |
| World Class Processing Inc (Ambridge, PA) |
| Worthington Specialty Process (Jackson, MI) |
| Worthington Steel Co (Monroe, OH) |
| Worthington Steel Co (Jackson, MI) |
| Precision Components (Chilliwack, BC)
Manufacturer |
| Redman Mfg. Co. (Ferndale, MI) |
| Berg Steel Pipe Corp (Panama City, FL)
Manufacturer |
| Bethlehem Lukens Plate (Conshohocken, PA)
Contract Manufacturer |
| Cemco (Pittsburg, CA)
Manufacturer |
| Dayton Steel Svc Inc (Rome, GA)
Manufacturer |
| Markin Tubing Inc (Wyoming, NY)
Manufacturer |
| Metco (Salt Lake City, UT)
Manufacturer |
| Paragon Tube Corp (Fort Wayne, IN)
Manufacturer |
| Parker-Hannifin Corp (Ashley, IN)
Manufacturer |
| Texan Tubular Sales (Houston, TX)
Manufacturer |
| U S Industrial Piping Inc (Kernersville, NC)
Manufacturer |
| U S Steel Tubular Products (Bakersfield, CA)
Distributor |
| Wa-Kay Industries Inc (Milford, MI)
Manufacturer |
| West Virginia Cold Drawn (Point Pleasant, WV)
Manufacturer |
