Starwin composite pipe is five layers: inside and outside layers are made of PPR, tightly bonded with melt adhesive to the mid-layer of aluminum core which is longitudinally welded in a butt-welded or overlapping wayStarwin pipes combine the advantages of plastic pipe and aluminum pipe. Features of composite pipe as follows:1. Compared with the metal pipe, Starwin composite pipe has the same strength, easy to bend, reluctant to retain former shape2. Super properties of high temperature, high pressure and corrosion resistance3. Smooth inner surface of the pipe reduces resistance to the fluids. The ability to conduct water is 30% more efficient4. Good property of heat preservation, heat conduction coefficient is 0.45W/m.k, which is much less than metal pipes and it can save insulation materials outside the pipe5. Easy to cut and install. It can be connected with special fittings instead of screw fittings; small diameter pipes can be rolled and packaged. Once received the pipes (bent radius >5d) can be cut to desired length and simply bent in order than many directional parts such as elbows or angles ate no longer recessing very convenient to install, much time and labor cost can be saved6. Lifespan of Starwin composite pipe is more than fifty years