The reliability and safety of the pneumatic ducts are essential for flight safety.A beam element model of the duct system is developed and the factors that impact the stress performance of the duct system are investig...The reliability and safety of the pneumatic ducts are essential for flight safety.A beam element model of the duct system is developed and the factors that impact the stress performance of the duct system are investigated,such as stress check standards,flight acceleration,internal temperature and internal pressure.The results show that the stress synthetic method as the stress check standard can obtain the more safety design results.The maximum stress of straight pipe is affected significantly by the acceleration in a plane perpendicular to straight pipe,while the maximum stress of bend pipe is greatly affected by the acceleration in the direction perpendicular to plane of the bend pipe.Meanwhile,internal pressure has little effect on the maximum stress of bend pipe and straight pipe.Temperature has little effect on the maximum stress of bend pipe while has a big impact on the maximum stress of straight pipe.展开更多
On the basis of analysis of the present roofbolter’s structures, the pneumatic vane motor roofbolter was proposed and researched. Structure principle of MFT 80Y type pneumatic vane motor roofbolter was expounded, a n...On the basis of analysis of the present roofbolter’s structures, the pneumatic vane motor roofbolter was proposed and researched. Structure principle of MFT 80Y type pneumatic vane motor roofbolter was expounded, a new project of the rotary shearing mechanism with integrating pneumatic vane motor with epicyclic reduction gear unit was carried out, the mathematical model for optimum design of the rotary shearing mechanism was set up, and the optimum design for the rotary shearing mechanism was made by MATLAB Optimization Toolbox. Finally, performance of MFT 80 type pneumatic vane motor roofbolter made with optimum method and the on site experiment were introduced.展开更多
A pneumatic reversible plough is developed, which complements to the tractor of 25.7-36.8 kW.The plough adopts the cylinder as reversing mechanism between the right and left plough bodies, and the cylinder can substit...A pneumatic reversible plough is developed, which complements to the tractor of 25.7-36.8 kW.The plough adopts the cylinder as reversing mechanism between the right and left plough bodies, and the cylinder can substitute the mechanical reversing mechanism. The pneumatic turnover allows the plough to be operated easily and turned over flexibly. Field experiment results show that indicators of plough performance meet the requirements of the relevant national standards.展开更多
文摘The reliability and safety of the pneumatic ducts are essential for flight safety.A beam element model of the duct system is developed and the factors that impact the stress performance of the duct system are investigated,such as stress check standards,flight acceleration,internal temperature and internal pressure.The results show that the stress synthetic method as the stress check standard can obtain the more safety design results.The maximum stress of straight pipe is affected significantly by the acceleration in a plane perpendicular to straight pipe,while the maximum stress of bend pipe is greatly affected by the acceleration in the direction perpendicular to plane of the bend pipe.Meanwhile,internal pressure has little effect on the maximum stress of bend pipe and straight pipe.Temperature has little effect on the maximum stress of bend pipe while has a big impact on the maximum stress of straight pipe.
文摘On the basis of analysis of the present roofbolter’s structures, the pneumatic vane motor roofbolter was proposed and researched. Structure principle of MFT 80Y type pneumatic vane motor roofbolter was expounded, a new project of the rotary shearing mechanism with integrating pneumatic vane motor with epicyclic reduction gear unit was carried out, the mathematical model for optimum design of the rotary shearing mechanism was set up, and the optimum design for the rotary shearing mechanism was made by MATLAB Optimization Toolbox. Finally, performance of MFT 80 type pneumatic vane motor roofbolter made with optimum method and the on site experiment were introduced.
文摘A pneumatic reversible plough is developed, which complements to the tractor of 25.7-36.8 kW.The plough adopts the cylinder as reversing mechanism between the right and left plough bodies, and the cylinder can substitute the mechanical reversing mechanism. The pneumatic turnover allows the plough to be operated easily and turned over flexibly. Field experiment results show that indicators of plough performance meet the requirements of the relevant national standards.