Resumen: A general expression to estimate the measurement uncertainty of double-flank gear rolling tests, according to the uncertainty budget method outlined in the GUM, is presented in this paper. This method is more precise than the comparator method and it allows us to know the individual contributions of each error source. Therefore, it is often applied in secondary calibration laboratories or industrial facilities that require a better understanding of their measurement process capability. Furthermore, the proposed expression can be adapted to estimate the measurement uncertainty of any gear tester configuration that works under rolling principles. The paper describes a case study where the uncertainty budget developed is applied to a double-flank worm gear rolling tester. Using experimental values of calibration and characterization of the gear tester, the expanded uncertainties of the rolling parameters Fi ”, Fr ” and fi ” were calculated. Finally, an optimized uncertainty budget is proposed where the main detected error sources are minimized improving therefore the measurement capacities of the tester. Idioma: Inglés DOI: 10.1016/j.precisioneng.2019.07.015 Año: 2019 Publicado en: Precision Engineering 60 (2019), 222-234 ISSN: 0141-6359 Factor impacto JCR: 3.108 (2019) Categ. JCR: ENGINEERING, MANUFACTURING rank: 19 / 50 = 0.38 (2019) - Q2 - T2 Categ. JCR: INSTRUMENTS & INSTRUMENTATION rank: 16 / 64 = 0.25 (2019) - Q1 - T1 Categ. JCR: ENGINEERING, MULTIDISCIPLINARY rank: 24 / 91 = 0.264 (2019) - Q2 - T1 Categ. JCR: NANOSCIENCE & NANOTECHNOLOGY rank: 54 / 103 = 0.524 (2019) - Q3 - T2 Factor impacto SCIMAGO: 1.226 - Engineering (miscellaneous) (Q1) - Nanoscience and Nanotechnology (Q2)