Use of notches in the shafts loaded by torque for improvement in accuracy of strain gauge measurements

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F68407700%3A21220%2F18%3A00327033" target="_blank" >RIV/68407700:21220/18:00327033 - isvavai.cz</a>

Result on the web

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DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Use of notches in the shafts loaded by torque for improvement in accuracy of strain gauge measurements

Original language description

One of the decisive factors for the sensitivity of the strain gauge instrumentation is the sensitivity of used strain gauges. For foil strain gauges, we talk about 1 μm / m [1]. This value is reached for steel components at a stress of about 2 MPa. It can be understood as a limiting one in terms of reliable detection. Since the ideal value of strain in the practical measurements for commonly used foil strain gauges should be about +/- 0.15 % for the wire versions and circa 0.1 % for the semiconductor versions, we talk about 20 - 25 MPa on the surface of measured steel component when the final error can theoretically decrease below 1 %. However, many engineering applications are out of this range and thus the uncertainty of the results is significantly growing. Especially in direct detection of torque on the gearboxes shafts in order to determine their mechanical efficiency, this is crucial. Generally, as well as in the case of the mentioned gearboxes, a certain possibility of solving the above mentioned problem is offered by constructional and technological notches in which the mechanical stress is locally concentrated. There are many various approaches available to estimate the rate of increase in local tension against nominal values on smooth surface of stable cross-sections, unfortunately without determining of the location of calculated extreme value. This is why we work with finite element method that eliminates mentioned drawbacks and allows us to reliably apply the direct strain gauge measurement in applications with extreme demands on accuracy of results as the mentioned efficiency of gearboxes is.

Czech name

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Czech description

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Type

D - Article in proceedings

CEP classification

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OECD FORD branch

20301 - Mechanical engineering

Project

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Continuities

N - Vyzkumna aktivita podporovana z neverejnych zdroju

Publication year

2018

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Article name in the collection

EAN 2018 56th conference on experimental stress analysis, Conference Proceedings

ISBN

978-80-270-4062-9

ISSN

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e-ISSN

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Number of pages

6

Pages from-to

239-244

Publisher name

Česká společnost pro mechaniku

Place of publication

Praha

Event location

Harrachov

Event date

Jun 5, 2018

Type of event by nationality

WRD - Celosvětová akce

UT code for WoS article

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