Mô tả
- Nippon Kokan K.K ., Japan
- Nippon Steel Corporation, Japan
- Kawasaki Steel Corporation, Japan
- Sumitomo Metal Ind. Ltd, Japan
- Benteler/ Mannesmann, Germany
- Siderca, Argentina
- Mannesman, Brazil
- Dalmine, Italy
- Shin Ho Steel Co., Japan
- Seah Steel Hyundai Pipe, Korea
- USS, America
