Petr Chvojka, Jiří Drobílek, Pavel Bach, Miloš Poláček, David Burian, Miroslav Janota
This paper reports on the tuning of dynamic properties of an experimental device used for identification of complex cutting forces that form a new force model, which should ensure a higher accuracy of the stability prediction. The dynamic properties of the device had to be tuned because of the natural frequency present in the working range. An investigation of the appropriate thickness and composition of plate springs and damping interlayers as well as the type of contact grip of the plate springs is the main task of the paper.
XXI IMEKO World Congress
· TC3
· 2015
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Ako Chijioke, Nicholas Vlajic
We report the implementation of a swept-sine dynamic force calibration system at NIST. This system is designed to perform primary calibration of force transducers at frequencies up to 2 kHz and forces up to 2 kN. We demonstrate the use of this system to measure the dynamic sensitivity of a strain-gauge based force transducer up to 2 kHz. The current dominant source of uncertainty in the system is angular motion of the calibration assembly.
XXI IMEKO World Congress
· TC3
· 2015
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John C. Bankert, Ako Chijioke
Dynamic calibration of force transducers using sinusoidal acceleration of load mass objects requires the accurate determination of the displacement field in such objects, in order to relate accelerations measured at one or a few locations on the object to its body-averaged acceleration. We present the results of finite element calculations of such displacement fields, and show that there are significant differences from the results of first-order approximations at calibration frequencies above ˜ 1 kHz for typical load mass objects.
XXI IMEKO World Congress
· TC3
· 2015
· Download
M. H. Hu, J. Wang, Y. Zhang, C. Q. Cai, R. L. Zhong, J. A. Ding, H. Yao, K. Jiao
The volume of a weight needs to be precisely measured for air buoyancy correction of the weight mass. To improve the measuring accuracy of volume determination with non-contact acoustic method, an acoustic measuring system with two measuring chambers is newly designed to compensate the non-linearly measuring errors. The volumes of mass standards ranging from 200 g to 5 kg are tested to evaluate the non-linearity errors of measurement, and a new test sequence is proposed theoretically to overcome the non-linearity of measurement and improve the measuring accuracy.
XXI IMEKO World Congress
· TC3
· 2015
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F. Hilbrunner, T. Fehling, S. Mühlich, M. Schreiber
Functions for calibration of weights in compliance with international standards are implemented in the current series of Sartorius manual mass comparators. Their intuitive software leads the user step by step through the entire mass comparison procedure. As a result, a record is generated, which contains the relevant data, including measurement uncertainty analysis. The present article discusses the determination of the uncertainty components and a possible method for budgeting these components in order to verify the suitability of mass comparators for various accuracy classes.
XXI IMEKO World Congress
· TC3
· 2015
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Hafid, Rachman Setiawan, Ghufron Zaid
A study on transmission ratio distortion of 1 MN lever-type force standard machine has been performed using finite element method (FEM). The study involves the determination of deformation that occurs in the arms due to loading calculated using a software-based finite element method. The dimensions of the arms are taken from the manufacturing data. For verification purposes, the transmission ratio distortion resulted from the finite element modeling is compared to the linearity error calculated from results of a series of calibration using load cells as force transfer standards. The finite...
XXI IMEKO World Congress
· TC3
· 2015
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Rafael S. Oliveira, Herman A. Lepikson, Thomas Fröhlich, René Theska, Wagner A. Duboc
This paper presents a new proposal for the dynamic test of torque transducers. The measurement methodology is presented in order to reach traceability in an angular acceleration regime of the measuring shaft. Different approaches to reach a test result are presented. A brief description of the assembly and methodologies applied are followed by the results of preliminary tests.
XXI IMEKO World Congress
· TC3
· 2015
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Klaus Fritsch
This paper presents the state-of-the-art calibration strategy for non-automatic weighing instruments (NAWI), based on the recently revised guideline EURAMET cg-18. Besides of the uncertainty at calibration, the document provides advice for the so-called uncertainty of a weighing result that describes the device performance during day-to-day use. The concept of minimum weight was added during a recent revision. The minimum weight is the smallest sample quantity that can be weighed on the device, still adhering to a predefined relative weighing tolerance requirement.
XXI IMEKO World Congress
· TC3
· 2015
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Hans Jörg Fraiss, Lioba Stenner, Dirk Röske
This paper describes the development of a torque calibration machine, based on a reference system, with a measurement range up to 400 kN·m and a target expanded relative measurement uncertainty of 0.1 %. Several factors that have to be considered as contributing to the uncertainty of measurement are discussed. The paper deals with multi-disc couplings, reference transducers and other mechanical components that are used to implement this calibration system.
XXI IMEKO World Congress
· TC3
· 2015
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Meng Feng, Zhang Zhimin, Zhang Yue
The paper describes two kinds of reference torque wrench, which were developed by our institute, and introduce the calibration methods by different torque standard machine. The experiment between two kinds of reference torque wrench has been done. The result was discussed in the paper.
XXI IMEKO World Congress
· TC3
· 2015
· Download