Papers by Keyword: Feed Speed

Abstract: The article is focused on the evaluation of the effects of factors of the high-speed hydro-abrasive stream technology during the splitting of construction steels 12 050 and 11 523 through a factor experiment. The experiment examined the effect and significance of two selected factors (type of material and movement speed of the technological head). Measured results are depicted through graphic and numerical relations, based on which new knowledge and recommendations for operators is formulated.

Abstract: The article describes the deep drilling tests of internal company research, which is aimed to determine the geometric tolerances as run-out, roundness and roughness, but also the shape and size of chips depending on cutting parameters. Further exploration subject was recorded using the actual engine power to determine the torque and axial force required for removing particles at the given cutting parameters. The results served to increase the productivity of deep drilling operations within the optimization process.

Abstract: The performance of three different micro-drills in drilling a machinable ceramic material has been evaluated in terms of the critical feed speed (mm/min) at a given rotation rate (rpm). The critical speed is the feed speed from and above which the chipping on the rear side of the machinable ceramic material takes place. The determined critical speed turns out to increase with rotation rate in the tested range of 2k-8k rpm, forming the critical boundary line. The drilling performance of the micro-drills can be evaluated quantitatively by using the position of the critical boundary lines in the space of feed speed vs. rotation rate: the upper the critical boundary line, the higher the drilling performance of the micro-drill.

Abstract: The text takes Z-Axis of precision machine tool as study object, and proceed the thermal character's experiment of Z-Axis feed system in different working condition (different Cooling strategy, different Feeding speed, load or not). The data of experiment shows the higher of the feed speed, the more heat is generated. Position accuracy can be increase by apply the right load and load is nearly none business with temperature rise. Cooling strategy is nearly none business with temperature rise and may cause the discretization of position accuracy.

Abstract: This research evaluated the planing performance of bamboo scrimber boards at three feed speeds and three cutting depths and used two methods to assess the finished surfaces. A macroscopic grade assessment was made according to ASTM D 1666-87 for visible planing defects. The other assessment was a microscopic scale roughness test measuring surface average roughness in terms of GB/T 12472. The visible results showed that the finished surface quality of bamboo resulted mainly in Grades and , with the main defect being torn grain. The two evaluations method showed consistent results in surface quality that the highest percentage of Grade was counted and the lowest roughness value occurred. Compared with the hardwood Sawtooth oak widely used in furniture industry in China, planning quality of bamboo scrimber board is better in terms of roughness.

Abstract: Radial-axial ring rolling is an important component of advanced manufacturing technology, but it has characteristics of high nonlinear on geometry and physics, so the radial-axial ring rolling process becomes very complex. In addition, the feeding mode of core roller has enormous influence on the quality of the rolled ring as well as the stability of the process. In this paper, a 3D rigid-plastic FE model of radial-axial ring rolling process is established, then three kinds of feed speed design ((1)constant of feed speed; (2)constant of feed in one rotary; (3)variation of feed speed)are offered. The difference of outer radius growth velocity, distribution of effective strain and temperature, rolling force, size of ring are analysised for the three kinds of feed methods. And, an optimized feed method is proposed base on analytic results, the optimized feed method can improve the quality of formed ring, and decrease the requirement of ring rolling mill.

Abstract: A three axis CNC milling machine was used for the cutting tests on the inclined surface of the 53HRC hardened steel, the hardened steel surface for the tests were keeping a inclined angle about 200 with the horizontal plane. According to the analysis of three axial milling force in the different milling strategies and different milling parameters, the effect of the different spindle speed and milling strategies for the cutting force was studied while the ball end finishing milling the hardened surface. The results of the tests were the good reaction for the rule of the cutting force which was changing with the spindle speed n and milling strategies, in addition, the results gave the reference of selecting optimum milling parameters of ball end finishing milling.

Abstract: Although cold ring rolling (CRR) process is largely used in the manufacturing of profiled rings like bearing races, research on this purpose has been scant. In this study, based on a validated finite element (FE) model, CRR process is simulated regarding the variable and constant feed speeds of the mandrel roll which lead to constant and variable values of the ring's diameter growth rates respectively using a 3D rigid-plastic finite element method (FEM). Major technological problems involved in the process including plastic deformation behavior, strain distribution and its uniformity, Cockcroft and Latham damage field and final outer diameter of ring are fully investigated. The results of simulations would provide a good basis for process control especially feed speed controlled mills and guiding the design and optimization of both cold and hot ring rolling process.

Abstract: In order to solve the problem that bone cells can not adhere to the pore wall, the paper introduces a new method that combines RP method with electrostatic spinning method is used for the preparation of a comprehensive new bone scaffold technology, and pays close attention on the automatic control of process parameters, the feeding speed. According to the model of feed speed and the diameter of nano-fibers, a theoretical guidance is given to the real-time control of feed speed, and a new feeding device, including the configuration software iFIX, a microcontroller, a sensor and stepping motor, is presented. It can give a real-time effective control of the feed speed, which provides a theoretical and technological basis for the quality of scaffolds prototyping.