On August 27, 2018, the US Department of Commerce announced an anti-dumping preliminary ruling on a cast iron sewer pipe imported from China (CastIronSoilPipe). Preliminary ruling: The dumping rate of the mandatory responding company HengTongCasting Co. Ltd. and other Chinese producers and exporters was 302.61%. The US Department of Commerce is expected to finalize the case on January 8, 2019. This case involves the United States to coordinate the tariff line number 7303.00.0030 under the product.

On February 16, 2018, in response to an application filed by the USCastIronSoilPipeInstitute on January 26, 2018, the US Department of Commerce announced an investigation into the initiation of anti-dumping and countervailing duties on cast iron sewer pipes imported from China. On March 9, 2018, the US International Trade Commission (USITC) issued a notice stating that the anti-dumping and countervailing industries imported from China's cast iron sewers were affirmative preliminary rulings. On June 26, 2018, the US Department of Commerce announced a countervailing preliminary ruling on cast iron sewers imported from China. According to US statistics, the US imports of China's cast iron sewage pipes in 2017 were about $11.5 million.