Technical Bulletin 1115
Thermal Aging of Insulation in Low-Temperature Applications
Dyplast's latest Technical Bulletin addresses "Thermal Aging", which is the gradual reduction of thermal insulation performance over time experienced by some insulants due to latest-generation (highly efficient) blowing agents diffusing out of the closed cells within the insulant. There are many insulants with initially "poor" thermal efficiencies that exhibit no thermal aging (i.e. they remain poor), and alternatively there are insulants with initially "superior" thermal efficiencies that even after aging continue to have superior thermal efficiencies. Thus over the lifetime of the insulation system this latter class of insulants offers energy savings that far exceed those of non-aging insulants!
1) Insulants manufactured with Hydrocarbons, HFCs, or HFOs generally have better (i.e. lower) thermal conductivities than those blown with air or air-equivalents;
2) Testing methods such as those used by ASTM strive to predict thermal aging and provide apples-to-apples comparisons between alternative insulants, yet it is incumbent on engineers/specifiers to execute due diligence;
3) Thermal aging protocols typically age specimens at ambient conditions that vary rarely reflect the conditions present at the actual application;
4) Thermal aging is mitigated (sometimes dramatically) by a number of factors – particularly low process temperatures and physical impediments to gas diffusion such as insulant layers, vapor barriers and jackets.
Please
contact Dyplast personnel at (800) 433-5551
or e-mail us at sales@dyplast.us
www.dyplast.com for complete information.
