HG/T 2-1198-1979 "Electrophoresis lacquer penetration determination method (steel tube method) " is a chemical industry standard, specifying the technical method for measuring the electrophoresis lacquer penetration by steel tube method. The content includes the test principle (using the deposition height of the film on the inner surface of the steel pipe during the Electrophoresis process to characterize the swimming penetration), instrumentation (steel pipe, Electrophoresis tank, etc.), operation procedures (steel pipe pretreatment, Electrophoresis parameter control, film deposition height measurement) and result evaluation. This standard is suitable for the detection of the penetrating force of the paint liquid in the electro-coating process, and provides a technical basis for evaluating the coating ability of Electrophoresis paint in the inner cavity of complex workpieces. It helps to optimize the process parameters of Electrophoresis and ensure the uniformity and integrity of the coating.