With the vigorous development of domestic medical care, the number of beds in large hospitals has been increasing, the production and supply of oxygen has also changed drastically, from the initial supply of oxygen cylinders to the current development of central oxygen supply by oxygen concentrator, which plays a vital role in clinical, therapeutic and emergency treatment. At present, the more widely used oxygen concentrators in large comprehensive hospitals in China are PSA series and VSA series oxygen concentrators, which are our main products.