Production Process of Polyurethane Insulating Pipe

There are three main production processes for polyurethane insulating pipes: "one-step method", "pipe-in-pipe method" and "foam spray method".


The "one-step method" is mainly used for steel pipes with a pipe diameter less than DN500. The process is limited with the pipe diameter range: the larger the pipe diameter, the difficulty of forming the insulation layer at one time will increase, and the eccentricity problem will become more serious. .


The "pipe-in-pipe method" is suitable for various pipe diameters, and the formation and eccentricity of the insulation layer are easier to control than the "one-step method". However, the process is more complicated, the foam density is uneven, the cavity is large, and it is difficult to make a large diameter outer protective tube.


"Foam spraying method" is a new type of process, using foam spraying equipment to spray polyurethane foam on the surface of the steel pipe directly, avoiding the eccentricity and forming problems of the anti-corrosion layer. The thickness and density of the insulation layer are consistent, which is convenient for monitoring. It is pretty good for large pipe diameters pipes.


Changsha Xiangjia Metal Materical Co., Ltd. has been engaged in the  steel pipe industry over 20 years and has now become a leader in the industry. If you have any inquiry, welcome to contact us!