3.6  Expanded perlite powder

Other than specified, the material shall conform to ASTM C549-02 Type I.

    3.6.1 Properties

Though the values do not conform to ASTM C549-02, the required properties of expanded perlite powder for side and suspended deck insulation shall be as follows.

 

(1)        Thermal conductivity (at 0°C)                                                           0.044 W/mK

(2)            Compacted density                                             minimum            48            kg/rn

                                                                                           maximum            64            kg/rn

 

 (3) Grading

Mesh size ( mm)

2.5

1.2

0.6

0.3

0.15

Volume percentage of passage (%)

100

85 ~ 100

40 ~ 80

20~ 45

5 ~ 25

 

(4) Organic content                                                 maximum             0.1 % ( weight)

(5) Moisture content                                               maximum             0.5% ( weight)

3.6.2 Other requirements

(1) Expanded perlite powder shall be site expanded and shall be conducted directly from the expander into the tank with no intermediate bulk handling.

(2) The pefifte shall be vibrated to assure that all voids are filled.

(3) When a source of supply for raw material of perlite has been established and approved by MIII, the source shall not be changed without Mills Approval.