What method is used to inspect the quality of ductile iron pipes, and what are the specific quality inspection methods? Here are some specific methods to help you in detail. Ductile iron pipes must meet the following quality requirements: 1. From the appearance point of view. Both the front and back of the ductile iron pipe must be flat and bright, without any obvious shortcomings such as honeycombs, cracks, dislocations, and cold partitions. Of course, some fine markings formed by cold casting that do not affect the function of the pipe are allowed. However, it is necessary to repair it and then smooth it before putting it into use; 2. In the place where the ductile iron pipe is connected, there should be no pitting, convex ridges or continuous grooves, etc., to avoid poor contact between the contact surfaces. The occurrence of leakage and other conditions; 3. The general outline of the flange at the socket of the ductile iron pipe must be clear, and the existence of grooved surface that affects the application is also not allowed.