The Tongzhou DN1800 regulating valve unit in Beijing section of the Tongzhou production of the South to North Water Transfer Project recently successfully completed an online installation and debugging, and the work has been accepted by the user. The DN1800 regulating valve unit is the core part of the Tongzhou project, shouldering the task of regulating the whole line. TWT operates in accordance with the relevant requirements for product self-test, the relevant size and installation quality being detected, submitted the relevant documents to the acceptance group regulating valve manufacturing. The inspection group reviewed the documents relating to the product manufacturing, dimensions, welding quality and appearance quality to ensure that the DN1800 regulating valve good appearance quality, dimensions meet the design requirements, production quality and that the testing results and TWT test results are consistent, and have agreed to acceptance and delivery of trial operation.