Users often buy acid and alkali resistant magnetic pumps, and the pipes are indispensable for installation. One user once heard that when installing the pumps and pipes, he found that the pump diameter did not match the size of the pipes, which made installation impossible. After communication, he found that the customer's pipe size was calculated by De, while the diameter of Shenyi acid and alkali resistant magnetic pumps is generally expressed by DN, regardless of the difference of one letter, The difference in size is at least ten millimeters.

De mainly refers to the outer diameter of the pipeline of the acid and alkali resistant magnetic pump, which is generally marked by De and needs to be marked in the form of outer diameter and wall thickness; It is mainly used to describe: seamless steel pipes, PVC and other plastic pipes, and other pipes that require clear wall thickness.

DN refers to the nominal diameter of the acid and alkali resistant magnetic pump of the pipeline, also known as the average outer diameter. The nominal diameter is the size of all pipeline accessories in the pipeline system represented by numbers. The nominal diameter is a convenient round integer for reference, which is only loosely related to the processing size. The nominal diameter is marked with the letter "DN" followed by a number.