[Help] Does anyone know how to choose the density of PIR insulation material?
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Everyone, PIR and HDPIR are also used as insulation materials or pipe supports for LNG pipelines. However, the density of PIR and HDPIR insulation materials ranges from 40 to 550 KG/M3. So how should one choose the appropriate density? For example, under what circumstances is which density usually chosen? Are there any standard criteria or guidelines for making such a choice?
This post was last edited by CHANGBAISHI on 2018-6-1 08:42. The principles behind heat retention are these three: heat conduction, convective heat transfer, and thermal radiation. Insulation with an internal vacuum in a sandwich structure is the best. If it is insulation material, it is best to check its thermal conductivity; the lower the value, the better. As for density, it is relative – those with a higher density are better than those with a lower density. For pipes with small diameters, there is a type of high-density foam (or sponge) or one that uses blowing agents; for larger-diameter pipes, glass wool with higher density is used, along with glass cloth coated with oil for waterproofing. It should be noted here that for insulation pipes used in the transportation of cryogenic liquids, a vacuum-insulated jacket is the best choice. However, it is important to pay attention to safety and explosion prevention measures here; there have been cases of overpressure explosions occurring due to liquid vaporization when a jacket-like structure is used. It is best to refer to the safety valve of the jacket shell on the cryogenic liquid storage tank. (For reference) Additionally, LNG pipelines are under the supervision of relevant **safety regulatory authorities; it is advisable to contact them for technical advice.
Seeing this post from many years ago, I’ll simply answer it to provide some reference for those who come across it later. Generally, there’s no need to choose a specific density for pipes or equipment; only supports require consideration regarding pressure resistance, with densities of 160 and 320 being common in such cases. Contact the manufacturers who provide quotes and tell them your ambient temperature and medium temperature; they will give you some references. Generally, PIR of 3 inches can be used in cryogenic environments, while 5 inches is the thickest available. If standards are of interest, you can look at ASTM C591.