CELLULAR GLASS INSULATION FOR UNDERGROUND HOT LINES

ONE-HUNDRED-AND-NINETY FEET OF 6-IN. PIPE USED TO CARRY STEAM CONDENSATE WAS INSTALLED WIT Foamglass insulation. Installation was made to evaluate the performance of Foamglass with particular attention given to improving the quality, efficiency and economy of installation techniques. The competitive position of Foamglass with regard to installation cost can be improved by elimination 1 the water cut-off collars if there is assurance that there would be no leaks resulting from internal corrosion 2 the cement coating of the insulation bore 3 the buttering of the butt and longitudinal joints and 4 the staggering of the sections of insulation. Improving the design of the expansion loop would also aid in reducing costs. Measurements of the temperature difference across the insulation indicated that Foamglass was satisfactory as a thermal insulator. The effectiveness of Foamglass as a moisture barrier is supposedly very good, but it will not be possible to check this property as the water table is below the pipe most of the time.