The ring flexibility of the HDPE double-wall corrugated pipe is simply to test the performance of the pipe after deformation under pressure. The testing process is not complicated: first, prepare the double-wall corrugated pipe sample and place it in a specified temperature environment for state adjustment, so that the sample reaches a stable state. Then, the sample is placed between parallel pressure plates and pressure is applied at a constant rate until the vertical inner diameter deformation of the pipe reaches 30%. After the deformation is reached, the pressure should be quickly removed. Then, the sample is carefully observed. If the pipe sample is not broken, there is no disengagement between the inner and outer walls, and the inner wall is not bent in reverse, it means that the ring flexibility of the double-wall corrugated pipe is qualified; on the contrary, if any of the above adverse phenomena occurs, it means that the ring flexibility is not up to standard. Through this test method, the performance of the double-wall corrugated pipe after pressure deformation can be intuitively judged to ensure that it can withstand external pressure without damage in practical applications, and ensure the quality of the project and the safety of use. PE double-wall corrugated pipe manufacturers, pipeline manufacturers, Hubei pe pipe manufacturers.