2010年4月28日,美国对来自中国的无缝碳钢和合金钢标准管线管和高压管发布反倾销肯定性初裁。2010年5月3日,由于相关当事人对倾销幅度计算提出异议,经审查,2010年5月28日商务部发布初裁结果修正的通知,修正后结果如下:
Tianjin Pipe International Economic and                           22.67%
 Trading Corporation.....................
         Produced by:Tianjin Pipe (Group)
          Corporation.....................
 Xigang Seamless Steel Tube Co., Ltd......                         57.30%
         Produced by: Xigang Seamless
          Steel Tube Co., Ltd., and Wuxi
          Seamless Special Pipe Co., Ltd..
 Jiangyin City Changjiang Steel Pipe Co.,                          57.30%
 Ltd.....................................
         Produced by: Jiangyin City
          Changjiang Steel Pipe Co., Ltd..
 Pangang Group Chengdu Iron & Steel Co.,                           57.30%
 Ltd.....................................
         Produced by: Pangang Group
          Chengdu Iron & Steel Co., Ltd...
 Yangzhou Lontrin Steel Tube Co., Ltd.....                         57.30%
         Produced by: Yangzhou Lontrin
          Steel Tube Co., Ltd.............
 Yangzhou Chengde Steel Tube Co., Ltd.....                         57.30%
         Produced by: Yangzhou Chengde
          Steel Tube Co., Ltd.............