scholarly journals Experimental Studies of an Asymmetric Multi-Bolted Connection under Monotonic Loads

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2353
Author(s):  
Rafał Grzejda ◽  
Arkadiusz Parus ◽  
Konrad Kwiatkowski
Keyword(s):  
Strain Gauge ◽  
Testing Machine ◽  
Experimental Studies ◽  
Measurement Data ◽  
Measuring System ◽  
Optimal Sequence ◽  
Bolted Connection ◽  
Initial Values ◽  
Measurement Results ◽  
Monotonic Loads

This article describes the experimental studies of a preloaded asymmetric multi-bolted connection in the exploitation state. The construction of two stands were introduced: for bolt calibration and for evaluating the bolt forces in a multi-bolted connection. The bolts were tightened in a specific optimal sequence, in three passes, monitoring the force values in the bolts using a calibrated strain gauge measuring system. The studies were conducted for the selected multi-bolted connection on an Instron 8850 testing machine. The measurement data were saved in MATLAB R2018b Simulink. The measurement results were analysed statistically and are presented via charts showing the distributions of the normalised values of the bolt forces as a function of the linearly increasing and decreasing exploitation loads. We show that the forces in individual bolts, after unloading the multi-bolted connection, change in relation to the initial values of their preload.

scholarly journals Health assessment of a multi-bolted connection due to removing selected bolts

2021 ◽  
Vol 49 (3) ◽  
pp. 634-642
Author(s):  
Rafał Grzejda ◽  
Arkadiusz Parus
Keyword(s):  
Strain Gauge ◽  
Experimental Studies ◽  
Health Assessment ◽  
Measuring System ◽  
Loading Conditions ◽  
Bolted Connection ◽  
Bolt Failure

In the paper, experimental studies of an asymmetric preloaded seven-bolted connection are presented. The tightening process of the connection was carried out with a wrench, monitoring the values of the bolt forces with a calibrated strain gauge measuring system. Two methods of bolt tightening were tested: in one and several passes. After all bolts were tightened, the selected bolts were removed, simulating bolt failure under the loading conditions of the connection. The influence of the method and sequence of bolt tightening on the distribution of bolt forces values after the introduction of failure states of some bolts was investigated. The results were statistically processed and presented in the form of graphs showing the distributions of normalised bolt forces values for all the considered failure cases.

scholarly journals Data Measuring System for Torque Measurement on Running Shafts Based on a Non-Contact Torsional Dynamometer

2019 ◽  
Vol 6 (2) ◽  
pp. e17-e23 ◽  
Author(s):  
S. M. Vanyeyev ◽  
D. V. Miroshnichenko ◽  
T. S. Rodymchenko ◽  
M. Protsenko ◽  
D. V. Smolenko
Keyword(s):  
Strain Gauge ◽  
High Speed ◽  
Measurement Data ◽  
Power Measurement ◽  
Measuring System ◽  
Bench Test ◽  
Torque Measurement ◽  
Performance Factors ◽  
Strain Gauge Dynamometer ◽  
And Performance

The need for power measurement transmitted by the running shaft has led to the need for using devices for measuring torque on the shaft. Of particular importance is the power measurement on high-speed machines, wherein some cases conventional measurement systems are either unsuitable or have low accuracy. Currently, data measuring systems are widely used in the researches of turbomachines. They allow to receive, process, transmit, store and display measurement data. Their application is relevant in relation to the priority of experimental study and subsequent modeling of characteristics and performance factors of expansion machines. The purpose of this research is a design and generation of the data measuring system for measuring torque on the running shaft of vortex expansion machines using a non-contact torsional dynamometer (strain-gauge clutch). The research has considered the results of the development of data measuring system, performed a theoretical analysis and presented the results of the practical application of the non-contact strain-gauge dynamometer designed for torque measurement on the shaft of low-power expansion machines when operating under bench test conditions. Has dealt with the problems of development, calibration. Keywords: data measuring system, torque, coupling, resistive-strain sensor, vortex expansion machine.

scholarly journals Information-measuring System to Study the Thermocouple with Controlled Temperature Field

2019 ◽  
Vol 19 (4) ◽  
pp. 161-169 ◽  
Author(s):  
Jinfei Wang ◽  
Orest Kochan ◽  
Krzysztof Przystupa ◽  
Jun Su
Keyword(s):  
Temperature Field ◽  
Experimental Studies ◽  
Measurement Data ◽  
Large Error ◽  
Measuring System ◽  
Metrological Reliability ◽  
Object A ◽  
Measured Object ◽  
Information Measuring ◽  
Information Measuring System

Abstract Error due to inhomogeneity is the main problem of thermocouples (TCs), e.g., during the operation of a type K TC, this error can reach 11-30 °C. Thus, metrological reliability of TCs is threatened by this error because there is a high risk of exceeding the permissible error when the temperature distribution along the TC legs changes. Such a large error, in turn, can threaten a proper operation or even safety of a measured object. A TC with controlled temperature field was proposed to cope with this error. An information-measuring system to perform proper measurements, measurement data acquisition and collection to construct mathematical models is proposed. Its property is high diurnal stability of ±(0.0025+0,002(X/XMAX–1) %. The requirements for the information-measuring system and its structure are considered in this paper. In particular, one of the key problems of such a sensor is how stable is its own temperature field under the influence of the temperature field of a measured object. The experimental studies were carried out using the developed system. They showed that the coefficient of penetration of the temperature field of the measured object is about 0.04. This allows decreasing error due to inhomogeneity by about 10-20 times.

scholarly journals Universal equipment for determining traction resistance of working bodies and their combinations designed for soil treatment

2020 ◽  
Vol 17 ◽  
pp. 00010
Author(s):  
Maxim P. Erzamaev ◽  
Dmitry S. Sazonov ◽  
Alexander E. Afonin ◽  
Leila S. Kurmanova ◽  
Evgeny S. Nesterov
Keyword(s):  
Strain Gauge ◽  
Measurement Data ◽  
Soil Treatment ◽  
Measuring System ◽  
Working Bodies ◽  
Universal Equipment

The article describes a strain gauge measuring system designed for measuring the traction resistance of tillage bodies and their combinations. Technical tools measure the traction resistance of the whole machine or one working body which is not an objective and reliable characteristics of combined tillage units. The design and principle of operation of the tensometric measuring system designed and manufactured by Samara State Agrarian University is described. It is used to determine the traction resistance of individual working bodies and their combinations. The results show that the measurement data on traction resistance are in compliance with the calculated values.

scholarly journals JUSTIFICATION OF TENSORISTOR CALIBRATION IN A COMPLEX WITH MEASURING EQUIPMENT

2021 ◽  
pp. 75-85
Author(s):  
Nataliia Fidrovska ◽  
Roman Ponomarenko ◽  
Evgen Slepuzhnikov ◽  
Dmytro Kozodoi
Keyword(s):  
Strain Gauge ◽  
Output Signal ◽  
Measuring Equipment ◽  
Functional Relationship ◽  
Experimental Studies ◽  
Strain Gauges ◽  
Strain Gages ◽  
Reliable Measurement ◽  
Complex Design ◽  
Measurement Results

The article describes the process of calibrating strain gauge and measuring equipment. Modern machines have a complex design of the shapes of parts and assemblies. The loads acting on them often do not allow the determination of the stress state by modeling or calculation when creating these structurally complex machines. Therefore, conducting experimental studies using the strain gauge method is an extremely important task in real time. But for such a study, it is necessary to calibrate the strain gauges. Calibration must be performed to determine the functional relationship between the load applied to the part to be tested and the equipment output. Depending on the size, as well as the configuration and other features of the investigated part, several methods of calibration of strain gages are used: direct and indirect. To obtain reliable measurement results, the calibration conditions should differ as little as possible from the conditions of experimental studies of the tested parts. Calibration must be performed to determine the functional relationship between the load applied to the part to be tested and the equipment output. Depending on the size, as well as the configuration and other features of the investigated part, several methods of calibration of strain gages are used: direct and indirect. To obtain reliable measurement results, the calibration conditions should differ as little as possible from the conditions of experimental studies of the tested parts. Calibration consists in finding a functional relationship between the load acting on the tested part and the output signal of the equipment. To do this, creating previously known loads on the part on which the strain gauges are glued, and comparing the value of these loads with the intensity of the output signal, their ratio is determined analytically or graphically. Electrotensometry uses bridge and half-bridge measurement circuits. The half-bridge circuit is widely used, especially in static processes, where one strain gauge is active, and the other is located in the area of the load and is used for temperature compensation. 

Experimental Studies Regarding the Mechanical Behaviour of Silicon-Coated and Uncoated P.A. 6.6 Fabrics

2014 ◽  
Vol 657 ◽  
pp. 377-381
Author(s):  
Mihaela Oleksik ◽  
Valentin Oleksik
Keyword(s):  
Uniaxial Tension ◽  
Testing Machine ◽  
Experimental Studies ◽  
Experimental Tests ◽  
Maximum Load ◽  
Woven Fabrics ◽  
Measuring System ◽  
Displacement Curve ◽  
Shear Loads ◽  
Tension Tests

These paper aims to present an experimental study for determining the mechanical properties of woven fabrics used for airbags manufacturing. In order to realise the study, there were chosen two types of fabric, one that is coated with silicon and one that is uncoated. The experimental tests that were carried out were uniaxial tension tests for samples extracted on the warp and on the weft direction, the Bias test, a test specific for shear loads and the dome test, a test specific for biaxial loads. For the uniaxial tension test the force-displacement curve was obtained and the maximum values of the loads and the displacement. For the last two tests (bias test and dome test) there have been determined the maximum load, the displacement at maximum load, but also the local major strains obtained. All tests were carried out on a tensile and compression testing machine Instron 5587, while for measuring the main strains there has been used also the optical measuring system Aramis.

Study of Bismuth Telluride Crystal Strength

2019 ◽  
pp. 1-8
Author(s):  
A. A. Gorbatovskiy
Keyword(s):  
Tensile Strength ◽  
Bismuth Telluride ◽  
Elasticity Modulus ◽  
Testing Machine ◽  
Bend Testing ◽  
Instron Testing Machine ◽  
Measurement Results ◽  
Strength Tests ◽  
Semiconductor Properties

The article presents results of strength tests of bismuth telluride prismatic samples obtained by growing crystals. These crystals have semiconductor properties and are used in the heat machines, the run-ability of which largely depends on the strength of crystals. Data available in the literature are significantly different from each other. It has been shown that, the most consistent strength tests results are obtained in case of bend testing. The measurement results of the elasticity modulus and tensile strength are given. For tests, an INSTRON testing machine with maximum direct stress of the 1000 H was used.

APPLICATION OF THE METHOD SPRINGY DEFORMATIONS OF BARREL DURING SHOT FOR DETERMINING THE INITIAL VELOCITY OF THE SHELL (MINE)

2019 ◽  
Vol 1 (12) ◽  
pp. 75-80
Author(s):  
Ye. Didenko ◽  
O. Stepanenko
Keyword(s):  
Strain Gauge ◽  
Initial Velocity ◽  
Radial Direction ◽  
Fire Control ◽  
Automatic Control Systems ◽  
Measurement Results ◽  
Initial Resistance ◽  
The Moment ◽  
The Many ◽  
Effective Use

One of the indicators of the effective use of artillery is the accuracy of the fire impact on the objects of enemy. The accuracy of the artillery is achieved by completing the implementation of all measures for the preparation of shooting and fire control. Main measures of ballistic preparation are to determine and take into account the summary deviation of the initial velocity. The existing procedure for determining the summary deviation of the initial velocity for the check (main) cannon of battery leads to accumulation of ballistic preparation errors. The supply of artillery units with means of determining the initial speed of the projectile is insufficient. Among the many known methods for measuring the initial velocity, not enough attention was paid to the methods of analyzing the processes that occur during a shot in the "charge-shell-barrel" system. Under the action of the pressure of the powder gases in the barrel channel and the forces of the interaction of the projectile with the barrel there are springy deformations in the radial direction. To measure springy deformations it is advisable to use strain gauge sensors. Monitoring of deformation in a radial direction by time can be used to determine the moment of passing a projectile past the strain gauge mounted on the outer surface of the barrel. In the case of springy deformations, the initial resistance of the sensor varies in proportion to its value. The speed of the shell (mine) in the barrel can be determined by time between pulses of signals obtained from strain gauges located at a known distance from each other. The simplicity of the proposed method for measuring the initial velocity of an artillery shell provides an opportunity for equipping each cannon (mortar) with autonomous means for measuring the initial velocity. With the simultaneous puting into action of automatic control systems can be automatically taking into account the measurement results. This will change the existing procedure for determining the total deviation of the initial velocity and improve the accuracy, timeliness and suddenness of the opening of artillery fire, which are components of its efficiency.

scholarly journals Modeling of German Low Voltage Cables with Ground Return Path

Energies ◽  
2021 ◽  
Vol 14 (5) ◽  
pp. 1265 ◽  
Author(s):  
Johanna Geis-Schroer ◽  
Sebastian Hubschneider ◽  
Lukas Held ◽  
Frederik Gielnik ◽  
Michael Armbruster ◽  
...  
Keyword(s):  
Low Voltage ◽  
Measurement Data ◽  
Analytical Calculation ◽  
Laboratory Measurement ◽  
Model Parameters ◽  
Calculation Methods ◽  
Modeling Approach ◽  
Measurement Results ◽  
Simulation Results ◽  
Return Path

In this contribution, measurement data of phase, neutral, and ground currents from real low voltage (LV) feeders in Germany is presented and analyzed. The data obtained is used to review and evaluate common modeling approaches for LV systems. An alternative modeling approach for detailed cable and ground modeling, which allows for the consideration of typical German LV earthing conditions and asymmetrical cable design, is proposed. Further, analytical calculation methods for model parameters are described and compared to laboratory measurement results of real LV cables. The models are then evaluated in terms of parameter sensitivity and parameter relevance, focusing on the influence of conventionally performed simplifications, such as neglecting house junction cables, shunt admittances, or temperature dependencies. By comparing measurement data from a real LV feeder to simulation results, the proposed modeling approach is validated.

scholarly journals Inverse Infiltration Modeling of Dike Covers Made of Dredged Material Using PEST and AMALGAM

Geosciences ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 41
Author(s):  
Tim Jurisch ◽  
Stefan Cantré ◽  
Fokke Saathoff
Keyword(s):  
Large Scale ◽  
Measurement Data ◽  
Fine Grained ◽  
Dredged Materials ◽  
Measurement Results ◽  
Large Scale Field ◽  
Eigenvalue Ratio ◽  
Ill Posed ◽  
Materials Used ◽  
Installation Technology

A variety of studies recently proved the applicability of different dried, fine-grained dredged materials as replacement material for erosion-resistant sea dike covers. In Rostock, Germany, a large-scale field experiment was conducted, in which different dredged materials were tested with regard to installation technology, stability, turf development, infiltration, and erosion resistance. The infiltration experiments to study the development of a seepage line in the dike body showed unexpected measurement results. Due to the high complexity of the problem, standard geo-hydraulic models proved to be unable to analyze these results. Therefore, different methods of inverse infiltration modeling were applied, such as the parameter estimation tool (PEST) and the AMALGAM algorithm. In the paper, the two approaches are compared and discussed. A sensitivity analysis proved the presumption of a non-linear model behavior for the infiltration problem and the Eigenvalue ratio indicates that the dike infiltration is an ill-posed problem. Although this complicates the inverse modeling (e.g., termination in local minima), parameter sets close to an optimum were found with both the PEST and the AMALGAM algorithms. Together with the field measurement data, this information supports the rating of the effective material properties of the applied dredged materials used as dike cover material.

Sign in / Sign up

Export Citation Format

Share Document