Investigation of a Hydrostatic Weighing Method for a 1 kg Mass Comparator

Metrologia ◽  
1984 ◽  
Vol 19 (4) ◽  
pp. 137-146 ◽  
Author(s):  
R Probst ◽  
M Kochsiek
Author(s):  
M.S. Razumov ◽  
P.V. Glazkov ◽  
V.S. Kochergin ◽  
A.S. Byshkin

The existing methods for detecting of casting defects and their disadvantages are considered. Hydrostatic weighing method is proposed for detecting of hidden fl aws by comparing the reference and calculated densities of the casting, method for calculating of the error is recommended. The adequacy of theoretical calculations is verifi ed experimentally


Author(s):  
Б. П. Савчук ◽  
Б. М. Савченко ◽  
Н. В. Сова ◽  
І. М. Костюк

Development of technology for the processing of cross liked EVA waste, followed by the use of polymer / polymer composite PVC / EVA as a filler. Method. The determination of the MFI was carried out in accordance with ISO 1133: 1997 on a capillary viscometer of constant pressure at a temperature of (190 ± 0,5) ° С and a weight of 2,16 kg. The thermostability  and  melting  point  are  determined  using  the  RM-200C  Hapro  rheometer  plastograph.  The mechanical properties were determined on a bursting machine according to the ASTM D638. Hardness - using  a  hard-gauge  with  a  Shore-D  scale,  the  density  by  hydrostatic  weighing  method  on  the  analytical scales RADWAG AS-X2.


Author(s):  
Guilherme Adroaldo Moraes Pereira ◽  
Silvana Corrêa Matheus ◽  
Diego Rodrigo Both ◽  
Mauri Schwanck Behenck

A good evaluation of the nutritional status requires knowledge on body composition, casting doubts on the accuracy of some indexes. herefore, the aim of this study was to analyze the accuracy of the following nutritional status indexes: Body Mass Index (BMI), BMI elevated to 2.5 (BMI2.5), Fat Mass Index (FMI) and BMI adjusted for fat mass (BMIfat). Participated of this study 280 subjects (aged 17-48 years), from which the results of BMI, BMI2.5, FMI and BMIfat indexes were analyzed, having the Hydrostatic Weighing method as reference. FMI presented the highest concordance value, but classiied as discrete (k=0.21). he other indexes presented small concordance with results of the reference method (k<0.20). In conclusion, none of the indexes investigated has good accuracy in assessing the nutritional status of the study group, considering that, although they show results of correlation with the reference method, they do not reach the minimum agreement criterion.


1955 ◽  
Vol 2 (18) ◽  
pp. 553-559 ◽  
Author(s):  
T. R. Butkovich

AbstractDensity of single crystals of ice from the Mendenhall Glacier near Juneau, Alaska, a temperate glacier, was determined by the hydrostatic weighing method. It was found that the densities of single crystals are slightly but measurably variable from one crystal to another. The values range from a minimum of 0.91712 gm./cm.3 to a maximum of 0.91728 gm./cm.3, when corrected for −3.5° C., for the eight crystals measured. Any imperfections such as Tyndall figures (hexagonal prismatic voids) were immediately evident in the density determinations, and correction for these imperfections give a corrected density essentially the same as that of clear specimens. Two clear crystal aggregate specimens tested had a lower density than the pure single ice crystals. An error computation gives the value of the estimated maximum error of the density determinations as ±2.1×10−5 gm./cm.3.


2019 ◽  
pp. 12-19
Author(s):  
Kinga Boroń

The paper shows the results of research aimed to assess the impact of high squeeze pressure on the porosity of AlZn5Mg alloy castings, including its distribution in slab-type castings with dimensions of 25 x 100 x 200 mm. The research was carried out on castings made by two methods: squeeze casting and gravity casting. The pressing was conducted at a pressure of 100 MPa at an initial mould temperature of 200°C. The research identified the middle and outer parts of the casting. Experimental research was preceded by numerical simulation of the casting solidification, then a porosity assessment was carried out using the hydrostatic weighing method, which was supplemented by structural observations. The results of the research showed a two-fold decrease in the porosity in the middle part of the casting which is most exposed to the occurrence of shrinkage voids formed in the final clotting phase. Structural tests revealed the occurrence of dispersed porosity in castings, mainly of shrinkage and / or shrinkage-gas origin. The impact of pressure of 100 MPa during solidification caused fragmentation of the primary structure of castings, which resulted in a higher grain density.


Author(s):  
D Sagdeev ◽  
◽  
Ch. Isyanov ◽  
I Gabitov ◽  
V Khairutdinov ◽  
...  

The density and dynamic viscosity of four light, medium, and heavy (extra-viscous) crude oil samples from Tatarstan Oil Field (Russian Federation) have been measured over the temperature range from (293 to 473) K (for density) and from (293 to 348) K (for viscosity) at atmospheric pressure (101 kPa). The density measurements were made using a new densimeter based on hydrostatic weighing method. The viscosity measurements of the same crude oil samples were made us-ing Brookfield rotational viscometer (DV-II+PRO, LVD-II+PRO). The combined expanded uncertainty of the density, viscosity, atmospheric pressure, and temperature measurements at 0.95 confidence level with a coverage factor of k = 2 is estimated to be 0.16 %, 1.0 %, 1.0 %, and 20 mK, respectively. For validation of the reliability and accuracy of the measured density data and correct operation of the new densimeter, all oil samples were measured using the pycnometric method. The present study showed that the densities measured using the new hydrostatic weighing densimeter (HWD) are agree with the values obtained with pycnometric method within (0.03 to 0.14) %. The measured density and viscosity data were used to develop widerange correlations as a function of temperature and API characteristics. The measured densities were represented using simple function of temperature (polynomial type) with API gravity dependent parameters with an accuracy of AAD within from (0.10 to 0.18) %. The measured viscosity data were also used to develop linear Arrhenius and VTF models. API gravity dependence of the Arrhenius parameters was studied.


2018 ◽  
Vol 224 ◽  
pp. 01125 ◽  
Author(s):  
Evgeny Ageev ◽  
Alexandr Altukhov ◽  
Alexandr Novikov

The wide use of the EED method for processing metal waste into powders for the purpose of their reuse and application in additive technologies is hampered by the lack in the scientific and technical literature of full-fledged information on the effect of the initial composition, regimes and media on the properties of powders and technologies of practical application. Therefore, in order to develop technologies for the reuse of electroerosive powders and to evaluate the effectiveness of their use, complex theoretical and experimental studies are required. The purpose of this work is the study of the porosity of additive products from electroerosive cobalt-chrome powders. For the implementation of the planned studies, wastes of the cobalt-chrome alloy of the brand KHMS “CELLIT” were chosen. As a working fluid, butanol (butanol-1) was used. For the production of cobalt-chrome powders, a unit for EED of conductive materials was used. Dispersion parameters: voltage 100 V, capacity 48 μF, repetition rate 120 Hz. Therefore, two or more pores because of the absence on the thin section of the visible boundary of their division can be fixed as one large. In addition, the method gives the distribution of pores in one plane of the sample, where narrow and wide sections of the sample fall, while in the hydrostatic weighing method and mercury porosimetry the pore sizes are fixed at their narrowest cross section. A consequence of these factors is the displacement of the function and distribution in the region of large pores. The porosity was determined using an Olympus GX51 optical inverted microscope with software for quantitative image analysis. Prepared samples had no traces of grinding, polishing or dying of structural components. Based on the results of conducted studies of the porosity of additive products from electroerosive cobalt-chrome powders, it has been experimentally established that the porosity does not exceed 1,06%.


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