Name of Standard: National ESZ force standard 20 kN
Code designation: ECM 150-3/08-042
Year of publication: 2008
Department: dpt. 8011 CMI LPM Praha
Guarantor: Ing. Petr Kašpar
Number of CMC lines provided: 1
| Mode | Scope | Uncertainty (k = 2) |
Tensile loading | 150 N – 20 kN | 4·10-5 |
Compressive loading | 150 N – 20 kN | 4·10-5 |
The state standard ESZ 20 kN is designed for calibration of standard force gauges with nominal forces up to 20 kN under tensile and compressive loading.
The standard was developed and constructed by the staff of the Force and Moment of Force Department of CMI LPM Prague under the direction of Ing. M. Chlumský as a replacement for the original ESZ 10 kN standard, which was destroyed during the flood in 2002 and no longer met the requirements for the primary force standard. The production of the parts was carried out in cooperation at MP NÁSTROJÁRNA in Úpice and at KOVO IDA in Malé Svatoňovice. After the completion of the force laboratory in Prague 5, the standard was installed in this laboratory. It was put into operation in 2005. Through theoretical and experimental work in 2002-2007, the team of the force department managed to prepare the standard scientifically and technically for the announcement as a state standard, which was successfully carried out in 2008.
The calibration force of the standard is generated by the action of the earth's gravitational field on the load bodies of the standard. The standard has one load cell system, which contains 30 load cells made of stainless austenitic steel.
The force generated by the standard is given by the equation:
Where stands for:
F | ...........…. | the power generated by the standard, |
m | ...........…. | the weight of the load bodies, |
g | ...........…. | the gravitational acceleration at the location of the load bodies, |
ρvzd | ...........…. | air density at the location of the load bodies, |
ρZT | ...........…. | density of load bodies. |
Obrázková galerie:
