The creep and creep recovery are important characteristics of Build-up system (BU-system). So, this paper is focused on the creep and creep recovery of several BU-systems. The creep and creep recovery of two different types of force transducers, including RTN and column type, are measured when applied 20%, 40%, 60%, 80%, and 100% of the rated loads and after unloading, respectively. Afterward built-up by these transducers, BU-systems with different structures and capacities are measured in order to investigate the creep and creep recovery behaviors of them and the differences between the BU-systems and single transducers.

The paper develops a negative step dynamic torque calibration machine and illustrates its working principle and critical technologies. The use of retracting actuators reduces significantly the fall time of the negative step torque, whereas air bearing yields high transfer accuracy of the dynamic torque. The experimental study is conducted and the results show that the fall time of the step torque reaches to millisecond level and the dynamic response up to 5800 Hz can be excited. Through uncertainty analysis, the expanded uncertainty of the presented calibration machine is better than 5 % (k = 2).

This paper describes PTB’s new 200 kN deadweight force standard machine with a large force range from 50 N up to 200 kN with lowest relative uncertainties of 0.001% in the range from 5 kN up to 200 kN which was possible by using deadweights of stainless steel in the quality of mass standards of class F1. The deadweights are adjusted according the gravity value and the masses are then determined with a relative expanded uncertainty of 3 × 10^-6. This maschine allows the investigation and calibrate force transducers in tension and compression without changing the installation position so that it is possible to determine the hysteresis effect (remanance) if the force changes from tension to compression.

One impulse force device is set up in CIMM to calibrate force transducers’ sensitivities with dynamic method. The free falling weight impacts the calibrated force transducer to generate large-amplitude impulse force up to 200 kN with (1~10) ms pulse duration, and one extra small inertia mass is installed on the top of the falling mass to generate small impulse force down to 20 N. The impulse force is measured by laser interferometer to trace the force to mass, time and length. Several piezoelectric transducers are calibrated with the impulse force calibration device and the amplitude sensitivity’s measurement repeatability is below 0.4 %.

The accurate measurement on the compressibility coefficient of density standard liquid at 2329kg/m³ (DSL-2329) plays an important role in the quality control for silicon single crystal manufacturing. A new method is developed based on hydrostatic suspension principle in order to determine the coefficient with high measurement accuracy. Two silicon single crystal samples with known density are immersed into a sealed vessel full of DSL-2329. The density of liquid is adjusted with varying liquid temperature and static pressure, so that the hydrostatic suspension of two silicon single crystal samples is achieved. The compression coefficient then calculated by using the data of temperature and static pressure at the suspension state. One silicon single crystal sample can be suspended at different state, as long as the liquid temperature and static pressure function linearly according to a certain mathematical relationship. By using the method based on hydrostatic suspension principle, the compressibility coefficient can be measured at the same time, and measurement precision can be improved due to avoiding the influence of liquid surface tension. This method was further validated experimentally, where the mixture of 1, 2, 3- tribromopropane and 1,2-dibromoethane is used as DSL-2329. The compressibility coefficient was measured, as 5.4 × 10^–10 Pa^–1.