Uncertainty Assessment in Temperature Uniformity Survey of Thermal Processing Equipment According to AMS2750 Aerospace Specification

Abstract

Thermal processing equipment used in the aerospace industry must meet the requirements of the processes for which they are intended. The periodic tests performed by calibration laboratories, according to the AMS2750 specification, are intended to ensure compliance with these equipment requirements. While this specification does not explicitly state the need for uncertainty calculation, it does specify that pyrometry laboratories must have an ISO/IEC 17025 Quality System accredited by a recognized regional body which is a member of the International Laboratory Accreditation Cooperation (ILAC). Therefore, the calculation of uncertainties is necessary. This work presents a methodology for conducting temperature uniformity surveys and uncertainty assessment in these tests. This methodology has been applied to four different types of equipment to analyse, in each case, the contributions of uncertainties and to assess their potential for improvement. The objectives that laboratories should aim for include improving measurement accuracy and reducing uncertainty components in order to meet the criteria of both AMS2750 and ISO/IEC 17025.