You are being redirected because this document is part of your ASTM Compass® subscription.
    This document is part of your ASTM Compass® subscription.


    Suitable Steady-State Methods for Measurement of Effective Thermal Conductivity in Rigid Insulations

    Published: 0

      Format Pages Price  
    PDF (268K) 17 $25   ADD TO CART
    Complete Source PDF (4.1M) 309 $94   ADD TO CART

    Cite this document

    X Add email address send
      .RIS For RefWorks, EndNote, ProCite, Reference Manager, Zoteo, and many others.   .DOCX For Microsoft Word


    The ASTM Test for Thermal Conductivity of Materials by Means of the Guarded Hot Plate (C 177-63) is a recognized technique for measurement of thermal conductance of insulations. This method may not be the optimum choice due to temperature range, material availability, and other factors. This paper describes three other steady-state techniques that may be used. Two are modifications of the basic comparative rod apparatus, and the third is a modification of the radial inflow apparatus. The two modifications of the comparative rod apparatus are designed to minimize or monitor or both the axial heat bypass and radial heat interchange effects. The modification to the radial inflow apparatus converts a cylindrical specimen to obtain heat flows through a plane surface. These modifications represent an improvement in the state of the art.

    The advantages of these procedures over the ASTM C 177-63 apparatus are smaller specimen size and wider temperature range. The disadvantages are that the precision and accuracy are not as good as that for the ASTM C 177-63 apparatus; however, an acceptable level for most engineering data may be obtained (< ±12 percent).

    Data on various candidates for the reusable surface insulation of the shuttle were measured by these methods and are reported.


    thermal conductivity, resistance, measurement, rigid insulations, radial flow, moldings, heat transmission

    Author Information:

    Engelke, WT
    Head, Applied Thermal Section, Southern Research Institute, Birmingham, Ala.

    Committee/Subcommittee: C16.30

    DOI: 10.1520/STP34775S