Double Pre-insulated Pipe

Double pre-insulated pipes are designed and manufactured to be used in hot water, hot oil, industrial lines and vapor lines at temperatures in between 120-450 ℃. Rock wool or calcium silicate is used as second isolation material. The second isolation material and its thickness is determined as the mid layer temperature will be reduced to the temperature which is the constant operation temperature of polyurethane (100-120 ℃).

Steel darn pipe (weldless pipe at ST 35.87 I quality) is used as service pipe in general. PE 100 casing pipe is used as cover (UV compounded, black, high density, polyethylene, density >940 kg/m3). The specifications and sizes of high density weldless polyethylene pipes conform the TS EN 253 standard. Due to the corona operation the casing does not separate from the pipe and permanent connections are being guaranteed with PUR rigid foam. Besides, the tensile strength assures until -50 degrees.

Isolation material is calcium silicate (Ca- Sil)+ polyurethane or rock wool + polyurethane. Polyurethane rigid (solid) foam includes compound A (poliol) and compound B (isocyanate). It can be continuously processed with heat conductivity 0,0274 W/mK or 0,0275 W/mK as per foam density at least 60kg/m3, fluid at various temperatures up to 120 ℃ and the peak temperature of fluid can increase to 140 ℃ from time to time. Rock wool is industrial type and it is prefabricated with aluminum foil. It is nonflammable and its density is in between 100-140 kg/m3. Heat conductivity coefficient is approximately 0,054 W/mK at 150℃.Calcium Silicate is an isolation material that does not contains asbestos. Its density is 240 kg/m3. Its thermal conductivity value is 0,07 W/mK at 200℃ and 0,1 W/mK at 400 ℃. It can be used up to temperatures in between 1000-1100 ℃.Double pre-insulated pipes’ isolation thickness values vary due to project, process and the temperature of the fluid passing through the pipe. Therefore, there is no standard production sizes.