Measurement results of the compressive strength of concrete specimens depend on the manner of force transfer by the testing machine. This performance is verified according to a standard using strain cylinders. However, the qualification or calibration of strain cylinders is not defined in the standard. This paper presents a new procedure for cylinder calibration. The measurand is defined. The standard quantity is modelised depending on the specific manner of loading during calibration. Uncertainties are computed using theoretical equations. The results of a first cylinder calibration are...
Force, Mass and Torque Measurements · TC3 · 2005 · Download
The paper describes improvement of the unsteady aerodynamic forces and moments measurements in an airfoil cascade. These loads are caused by shifting and angular vibrations of airfoils. The improvement was achieved by taking airfoils and other elements deformations, induced by action of innercia and measured aerodynamic firces, in consideration during the calibration and measurement process. The different variants of airfoils supporting are considered.
Force, Mass and Torque Measurements · TC3 · 2005 · Download
In order to verify material testing machine, constant test speed is necessary for satisfactory results. According to EN 10002-2 or EN ISO 7500-1 standards, all the verifications shall be carried out with a slowly increasing force. This means that test speed should be low as much as possible. But it is not specified in the standards. If the machine is capable to hold the selected force in quasi-static conditions, in this case selected forces are applied step by step during verification. In some cases, material testing machine cannot capable to hold quasi-static force. In this case, it causes...
Force, Mass and Torque Measurements · TC3 · 2005 · Download
Different heat treatment processes can be applied on the spring element of a force transducer in order to obtain good and satisfactory performance. The manufacturers are generally focused on the improvement of performance by applying different heat treatments on spring material, and no information is in free circulation regarding the process-performance relationships of transducers due to tight competition in the market. The study covers the attempts of different heat treatments on spring element using AISI 4340, which is regarded as one of the best spring materials for force transducer...
Force, Mass and Torque Measurements · TC3 · 2005 · Download
The UME “M One” mass comparator system was installed at the UME to be used research activities in describing an optimum transfer standard as buoyancy artifacts and comparing buoyancy artifacts between in air and vacuum environments and also 1 kg mass standards. The system were designed and manufactured by Mettler Toledo. The reproducibility of the mass comparator is 0,4 µg under vacuum.
Force, Mass and Torque Measurements · TC3 · 2005 · Download
A machine was designed and manufactured for endurance tests of nonautomatic weighing instruments according to the regulation of OIML R76-1-2 and EEC/90/384. An AC servomotor directly actuates the machine. It has also control panel and software. It has a compact module consisting of ball screw mechanism and a handler, made of polyamide material, specially designed. It is used for handling nine numbers of standard masses, knops headed type, with ranges 100 g up to 50 kg. There are nine types of weight carriers for each different mass. Some parameters for loading and unloading of masses can be...
Force, Mass and Torque Measurements · TC3 · 2005 · Download
An automatic turntable system was designed for 500 kg mass comparator. The turntable system was constructed in one piece due to dimensional stability and calibration of cylindrical also rectangular shaped weights between 100 kg and 500 kg weights. This system is controlled by PLC, optionally it is possible to use manually.
Force, Mass and Torque Measurements · TC3 · 2005 · Download
Today much higher speed of operation and highly accurate weighing of packages during crossing a conveyor belt has been getting more and more important in the food and distribution industries etc. Continuous weighing means that masses of discrete packages on a conveyor belt are automatically determined in sequence. Making the best use of new weighing scale called a multi-stage conveyor belt scale which can be created so as to adjust the conveyor belt length to the product length, we propose a simplified and effective mass estimation algorithm under practical vibration modes. Conveyor belt...
Force, Mass and Torque Measurements · TC3 · 2005 · Download
This paper highlights how the S.I unit of force (Newton) is realized in the Kenya Bureau Of Standards force laboratory. The use of the 1MN Multi-Lever Force Standard Machine. The dissemination of the Unit (N) in the organization (KEBS) and in the Kenyan industry. Calculation of uncertainty of measurement.
Force, Mass and Torque Measurements · TC3 · 2005 · Download
Typically, differential pressure transmitters used for fiscal monitoring and custody transfer purposes are often calibrated with the low side open to atmosphere. If the relevant line pressure is not applied during the calibration of differential pressure transmitters, the validity of the calibration is questionable. It is widely acknowledged that the output of differential pressure transmitters changes with line pressure due to mechanical distortion of the wetted parts. Although the distortion is thought to be extremely small, the high degree of sensitivity results in a significant change of...
Force, Mass and Torque Measurements · TC3 · 2005 · Download