Interlaboratory Comparison of the Guarded Horizontal Pipe-Test Apparatus: Precision of ASTM (American Society for Testing and Materials) Standard Test Method C-335 Applied to Mineral-Fiber Pipe Insulation

摘要

Apparent thermal conductivity of refractory pipe insulation from the same production lot was measured by seven different laboratories. The comparison assessed the precision and bias of the ASTM Test for Measurement of Steady-State Heat-Transfer Properties of Horizontal Pipe Insulation (C 335). For all test results from all seven participants, the standard deviation was 5%. This value is offered as the estimated precision of the horizontal pipe-test method. The accuracy of the pipe-test method cannot be estimated from the data obtained in the intercomparison.