1.There are three styles: vertical single layer,double layers,and 3 layers structure. 2.The polishing precision of inside wall is Ra0.45. The inside of pipe are heated by steam winding, the spring tape or cooled by cooling water. 3.The outside layer that keeps warm uses polyurethane foam or pearwool. 4.The pars that touch the medical liquid adopt the 316L material, the other parts 304 material 5.There are water entrance, circumfluence e