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• 2011-02-22 Welding Wires for Hardbanding
• 2011-02-22 Processing of OCTG and Special Thread
• 2011-02-22 Paint products
• 2011-02-22 Internal Coating
• 2011-02-22 Hilong’s Proprietary Products.rar(2)
• 2011-02-22 Hilong’s Proprietary Products.rar(1)
• 2011-02-22 Anti-corrosion for Oil Pipe