1 XPS foamed board,has a perfect closed-pore alveolate structure 2 its density,water absorption,coefficient of heat conducting and the coefficient of steam pervasion are all lower than those of other board heat preservasion materials 3 They have the characteristics of strong intensity,light material,airtight,anticorrosion,aging resistance,low cost,etc 4 It has been widely used in the fields of heat preservation and heat insulation in the construction industry,frost resistance of the highway,railway,airport,square and household fitment.it is the generally known as the best heat preservation material in the market at present.