Sealing quality strongly affects heat pipe performance, but few studies focus on the process of heat pipe sealing. Cold welding sealing technology based on a stamping process is applied for heat pipe sealing. The bond...Sealing quality strongly affects heat pipe performance, but few studies focus on the process of heat pipe sealing. Cold welding sealing technology based on a stamping process is applied for heat pipe sealing. The bonding mechanism of the cold welding sealing process （CWSP） is investigated and compared with the experimental results obtained from the bonding interface analysis. An orthogonal experiment is conducted to observe the effects of various parameters, including the sealing gap, sealing length, sealing diameter, and sealing velocity on bonding strength. A method with the utilization of saturated vapor pressure inside a copper tube is proposed to evaluate bonding strength. A corresponding finite element model is developed to investigate the effects of sealing gap and sealing velocity on plastic deformation during the cold welding process. Effects of various parameters on the bonding strength are determined and it is found that the sealing gap is the most critical factor and that the sealing velocity contributes the least effect. The best parameter combination （AIB3CID3, with a 0.5 mm sealing gap, 6 mm sealing length, 3.8 mm sealing diameter, and 50 mm/s sealing velocity） is derived within the experimental parameters. Plastic deformation results derived from the finite element model are consistent with those from the experiment. The instruction for the CWSP of heat pipes and the design of sealing dies of heat pipes are provided.展开更多
Positive Pressure Protective Clothing(PPPC)is the most important personal protective equipment for BSL-4 laboratory and a primary barrier to avoid exposure to pathogenic microorganisms.However,during the process of st...Positive Pressure Protective Clothing(PPPC)is the most important personal protective equipment for BSL-4 laboratory and a primary barrier to avoid exposure to pathogenic microorganisms.However,during the process of storage,utilization,disinfection and inspection,it will be inevitable damaged in varying degrees.PPPC is expensive;therefore,effective repairs become an important procedure to prolong service life of PPPC and to ensure their protective function.This paper analyzed those common damages in PPPC during routine BSL-4 laboratory operations and provided repair plans which can be used as references for users and maintenance personnel.展开更多
基金Supported by National Natural Science Foundation of China(Grant Nos.51175186,51675185)Guangdong Provincial Natural Science Foundation of China(Grant No.S2013020012757)EU project PIIF-GA-2012-332304(Grant No.ESR332304)
文摘Sealing quality strongly affects heat pipe performance, but few studies focus on the process of heat pipe sealing. Cold welding sealing technology based on a stamping process is applied for heat pipe sealing. The bonding mechanism of the cold welding sealing process （CWSP） is investigated and compared with the experimental results obtained from the bonding interface analysis. An orthogonal experiment is conducted to observe the effects of various parameters, including the sealing gap, sealing length, sealing diameter, and sealing velocity on bonding strength. A method with the utilization of saturated vapor pressure inside a copper tube is proposed to evaluate bonding strength. A corresponding finite element model is developed to investigate the effects of sealing gap and sealing velocity on plastic deformation during the cold welding process. Effects of various parameters on the bonding strength are determined and it is found that the sealing gap is the most critical factor and that the sealing velocity contributes the least effect. The best parameter combination （AIB3CID3, with a 0.5 mm sealing gap, 6 mm sealing length, 3.8 mm sealing diameter, and 50 mm/s sealing velocity） is derived within the experimental parameters. Plastic deformation results derived from the finite element model are consistent with those from the experiment. The instruction for the CWSP of heat pipes and the design of sealing dies of heat pipes are provided.
基金This work was supported by Major Infectious Diseases such as AIDS and Viral Hepatitis Prevention and Control of Major Projects(2017ZX10304403-004)。
文摘Positive Pressure Protective Clothing(PPPC)is the most important personal protective equipment for BSL-4 laboratory and a primary barrier to avoid exposure to pathogenic microorganisms.However,during the process of storage,utilization,disinfection and inspection,it will be inevitable damaged in varying degrees.PPPC is expensive;therefore,effective repairs become an important procedure to prolong service life of PPPC and to ensure their protective function.This paper analyzed those common damages in PPPC during routine BSL-4 laboratory operations and provided repair plans which can be used as references for users and maintenance personnel.
