We studied consecutive impact loading on woven high-modulus polyethylene rope, which is used in robotics fields. An impact tester was developed to conduct the experiments. Five consecutive impact loads (five drops) we...We studied consecutive impact loading on woven high-modulus polyethylene rope, which is used in robotics fields. An impact tester was developed to conduct the experiments. Five consecutive impact loads (five drops) were applied to the rope and the stiffness of the loading part that corresponds to each drop was evaluated. The stiffness of the woven ropes was affected strongly by consecutive impact loading. The change in stiffness is undesirable in some applications such as in robotic fields. Therefore, we have proposed a method that can optimize changes in stiffness by applying a preload before impact testing (preload treatment). The experimental results show that preload is an efficient way to reduce changing rope stiffness. We have also proposed an empirical equation that can estimate the rope stiffness after arbitrary preload treatment, and this equation is a function of the number of drops and the static preload level. The equation can be used to determine the preload treatment conditions to stabilize the stiffness of the woven ropes before they are used in engineering fields.展开更多
The effect of vinyltrimethoxysilane(VTMS)graft and SiO_(2) on the structure and mechanical properties of silane-grafted-polyethylene/SiO_(2)(VTMS-g-PE/SiO_(2))nanocomposite fibers and ropes was studied.Scanning electr...The effect of vinyltrimethoxysilane(VTMS)graft and SiO_(2) on the structure and mechanical properties of silane-grafted-polyethylene/SiO_(2)(VTMS-g-PE/SiO_(2))nanocomposite fibers and ropes was studied.Scanning electron microscopy(SEM),Fourier transfer infrared(FT-IR),differential scanning calorimetry analysis(DSC)and tensile mechanical tests were performed to characterize the morphology,thermal and mechanical properties of nanocomposite fibers and ropes.The results revealed that the SiO_(2) nanoparticles were well dispersed throughout the polymeric matrix.With increasing SiO_(2) content,T_(m),the melt peak width and X_(c),degree of crystallinity,of VTMS-g-PE/SiO_(2) nanocomposite fibers increased.The breaking load and breaking strength of the nanocomposite fiber ropes were remarkably improved compared to pure PE fiber ropes and elongation at break was also decreased.展开更多
In this paper,six specimens made by four kinds of fiber materials used in sea cage were selected,the percentage of elongation of them were measured by two methods.The two forms regression equation of percentage of elo...In this paper,six specimens made by four kinds of fiber materials used in sea cage were selected,the percentage of elongation of them were measured by two methods.The two forms regression equation of percentage of elongation and relatively load rate were established,one of them expressed the power function,and another expressed the linear function.The constant load elongation of new ropes and simulated loaded ropes,and the method to estimate at breaking elongation were brought forward.The attenuation of extensibility of rope during load and unload test according to 50% rated breaking load of it was discussed.The result of test and study on the elongation performance of the fiber ropes show that it may be the reference for the design,to calculate the length of the ropes used in the sea cage as traction cordage or anchor hawser.展开更多
文摘We studied consecutive impact loading on woven high-modulus polyethylene rope, which is used in robotics fields. An impact tester was developed to conduct the experiments. Five consecutive impact loads (five drops) were applied to the rope and the stiffness of the loading part that corresponds to each drop was evaluated. The stiffness of the woven ropes was affected strongly by consecutive impact loading. The change in stiffness is undesirable in some applications such as in robotic fields. Therefore, we have proposed a method that can optimize changes in stiffness by applying a preload before impact testing (preload treatment). The experimental results show that preload is an efficient way to reduce changing rope stiffness. We have also proposed an empirical equation that can estimate the rope stiffness after arbitrary preload treatment, and this equation is a function of the number of drops and the static preload level. The equation can be used to determine the preload treatment conditions to stabilize the stiffness of the woven ropes before they are used in engineering fields.
基金This work was supported by the National Natural Science Foundation of China(Grant No.31502213)Special Scientific Research Funds for Central Non-profit Institutes(East China Sea Fisheries Research Institute)(Grant No.2015T01)the National Key Technology R&D Program(Grant No.2013BAD13B02).
文摘The effect of vinyltrimethoxysilane(VTMS)graft and SiO_(2) on the structure and mechanical properties of silane-grafted-polyethylene/SiO_(2)(VTMS-g-PE/SiO_(2))nanocomposite fibers and ropes was studied.Scanning electron microscopy(SEM),Fourier transfer infrared(FT-IR),differential scanning calorimetry analysis(DSC)and tensile mechanical tests were performed to characterize the morphology,thermal and mechanical properties of nanocomposite fibers and ropes.The results revealed that the SiO_(2) nanoparticles were well dispersed throughout the polymeric matrix.With increasing SiO_(2) content,T_(m),the melt peak width and X_(c),degree of crystallinity,of VTMS-g-PE/SiO_(2) nanocomposite fibers increased.The breaking load and breaking strength of the nanocomposite fiber ropes were remarkably improved compared to pure PE fiber ropes and elongation at break was also decreased.
文摘In this paper,six specimens made by four kinds of fiber materials used in sea cage were selected,the percentage of elongation of them were measured by two methods.The two forms regression equation of percentage of elongation and relatively load rate were established,one of them expressed the power function,and another expressed the linear function.The constant load elongation of new ropes and simulated loaded ropes,and the method to estimate at breaking elongation were brought forward.The attenuation of extensibility of rope during load and unload test according to 50% rated breaking load of it was discussed.The result of test and study on the elongation performance of the fiber ropes show that it may be the reference for the design,to calculate the length of the ropes used in the sea cage as traction cordage or anchor hawser.
