In developing the new friction welding technology, the thermal elastic-plastic stress analysis by the finite element method was carried out to seek the suitable welding conditions such as the friction pressure, the fr...In developing the new friction welding technology, the thermal elastic-plastic stress analysis by the finite element method was carried out to seek the suitable welding conditions such as the friction pressure, the friction speed and the upset pressure. The results obtained are as follows: Heat transfer to the specimens and the intermediate material during friction process was made clear; The operational conditions such as the rotation number of the intermediate material and the friction pressure to reach the liquidus in the interface could be estimated; Further, as the overhang length near the interface is well related to the joint efficiency, we tried to obtain the operational conditions by numerical analysis to acquire a certain length of the overhang length near the interface.展开更多
By extracting the outlet pressure data of gas regulators,this paper uses the EMD toolbox of the MATLAB software,which can perform data decomposition and the Hilbert-Huang Transform to find the rules with fault data.Ev...By extracting the outlet pressure data of gas regulators,this paper uses the EMD toolbox of the MATLAB software,which can perform data decomposition and the Hilbert-Huang Transform to find the rules with fault data.Eventually,the medium-low pressure gas regulator fault criterion can be established.展开更多
文摘In developing the new friction welding technology, the thermal elastic-plastic stress analysis by the finite element method was carried out to seek the suitable welding conditions such as the friction pressure, the friction speed and the upset pressure. The results obtained are as follows: Heat transfer to the specimens and the intermediate material during friction process was made clear; The operational conditions such as the rotation number of the intermediate material and the friction pressure to reach the liquidus in the interface could be estimated; Further, as the overhang length near the interface is well related to the joint efficiency, we tried to obtain the operational conditions by numerical analysis to acquire a certain length of the overhang length near the interface.
基金supported by Science and technology project of Beijing in 2015 from Beijing Municipal Science&Technology Commission
文摘By extracting the outlet pressure data of gas regulators,this paper uses the EMD toolbox of the MATLAB software,which can perform data decomposition and the Hilbert-Huang Transform to find the rules with fault data.Eventually,the medium-low pressure gas regulator fault criterion can be established.