D. Zvizdic, L. Grgec Bermanec, W. Schultz, T. Veliki
This paper presents characterization of diving-bell manometer in the gauge pressure range from -1.0 up to 3.0 kPa in the Croatian national pressure laboratory - Laboratory for Process measurement (LPM), located at the Faculty of Mechanical Engineering and Naval Architecture (FSB), University of Zagreb. The work points out comparison of two independent methods for diving-bell effective area determination i.e. determination based on dimensional measurements as well as determination of the effective area by a pressure comparison method. The dimensional measurements were performed in the...
Cultivating Metrological Knowledge
· TC16
· 2007
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T. Kobata,M. Kojima, and H. Kajikawa
A remote calibration technology for disseminating pressure standards has been developed. Currently, the technology is developed in two different pressure ranges. One is gas differential pressure from 10 Pa to 10 kPa with the line pressure of atmospheric pressure and the other is hydraulic pressure from 10 MPa to 100 MPa in gauge mode. In both pressure ranges, the measurement protocol for the remote calibration using a transfer standard has been examined. Also the transfer standard for the remote calibration has been developed in either pressure range. Using the protocol and the developed...
Cultivating Metrological Knowledge
· TC16
· 2007
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T. Kobata
A new fully automated system for calibrating a pressure balance is described. The system consists of two automated pressure balances, a pressure controller, two air-operated constant volume valves, a precise pressure transducer, a device for measuring environmental condition, a computer and the program developed. In the system, one pressure balance is used as a standard and the other is calibrated and/or evaluated. To determine the equilibrium state between two pressure balances accurately, the cross-float measurement using the comparator method is performed. In this paper, the details of...
Cultivating Metrological Knowledge
· TC16
· 2007
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S. Woo, I. Choi, H. Song, B. Kim
The accurate measurement of differential pressure at low-line pressure is important in many industrial and commercial activities. The Korea Research Institute of Standards and Science(KRISS) has completed the development of a low differential pressure primary standard covering a range from 1 Pa to 15 kPa for operation with line pressures of 100 kPa. The standard is based on a double pressure balance and includes a test-instrument manifold with pressure controllers. It has a peculiar automatic weight handling mechanism which enables the various weights easily to add or remove from the piston...
Cultivating Metrological Knowledge
· TC16
· 2007
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M. Bair, P. Delajoud and M. Girard, DH INSTRUMENTS
The pressure crossfloat is a well established method for comparing the output of piston gauges with various media. The crossfloat is the most common method for determining the area of a test piston-cylinder relative to a reference piston-cylinder. The traditional crossfloat procedure is a tedious manual process that is highly dependent on operator skill, patience and experience. Due to the need to access the masses to make small mass adjustments, operation is normally gauge mode only. In order to meet a high demand for low pressure, gas operated piston gauge systems, DHI has designed and...
Cultivating Metrological Knowledge
· TC16
· 2007
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Pierre Otal, Jean-Claude Legras
The LNE standards around 1 Pa absolute are constituted by a force-balanced piston gauge (FPG), 100 Pa capacitance diaphragm gauges (CDGs), and spinning rotor gauges (SRGs). The key parameters limiting the performance of the devices are presented. The results of a comparison involving at the same time the three instruments are presented and discussed, as well as the capabilities of these instruments in this range. As an example, the repeatability of measurements, and the linearity error in the comparison are less than 2 mPa.
Cultivating Metrological Knowledge
· TC16
· 2007
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In-Mook Choi, Sam-Yong Woo, and Boo-Shik Kim
Low-pressure detection technology utilizing the field emission of carbon nanotubes (CNTs) is introduced. The use of an ionization gauge is a viable alternative method for measurements at low pressure levels, but their use is limited by such factors as the bulky size, high power consumption, x-ray radiation, heat and light generation, and outgassing associated with this type of gauge. To overcome the limitations of conventional ionization gauges, CNTs have been proposed as an electron source. The performance of a CNTbased low-pressure gauge, including the sensitivity, measurement range, and...
Cultivating Metrological Knowledge
· TC16
· 2007
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Nieves Medina, Salustiano Ruiz, Carmen Matilla
In the near future new pressure standards will be operative at CEM. These standards together with the existing will provide traceability to the whole pressure range. These standards are a mercury column, a force piston gauge and a static expansion system. The mercury column is a U-shaped steel tube filled with mercury. Its measurement principle is Torricelli´s law. The height difference between the two columns is measured by means of a single-beam helium–neon laser interferometric system. Its measurement range is from 1 kPa up to 130 kPa in absolute, relative and differential modes. The...
Cultivating Metrological Knowledge
· TC16
· 2007
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Christian Wüthrich
The METAS static expansion system was built in 2004 and has been extensively characterised during the last two years. The system consists of four expansion stages allowing the generation of calculable pressures ranging from 5·10 -6 Pa up to 2000 Pa. Uncertainty calculation yields a relative uncertainty of 0.001 (k=2) for the volumetric ratio of the expansion stage. The relative uncertainty on the pressure obtained after expansion is 0.003 above 10 Pa, it is still 0.01 at 2·10 -4 Pa. Measurement of the accommodation coefficient of two SRG from 10 -5 Pa up to 0.1 Pa has shown no significant...
Cultivating Metrological Knowledge
· TC16
· 2007
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Anita Calcatelli
The available measuring devices in the ultra high and extreme high vacuum range with their limitations are presented on the basis of the ultimate attainable pressure. New miniature gauges and calibration devices up now available are shortly reviewed. A complete bibliography is presented.
Cultivating Metrological Knowledge
· TC16
· 2007
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