The lifetime of roll-bits with inserted tooth will be obviously decreased while drilling in strata and the tungsten carbide can be integrally separated from the roll-cone,which will need more trip out time to replace ...The lifetime of roll-bits with inserted tooth will be obviously decreased while drilling in strata and the tungsten carbide can be integrally separated from the roll-cone,which will need more trip out time to replace the roller bit.This study provides an entire analysis on stress as well as strength for teeth and tooth holes in loaded conditions.Qualities of tooth drop from matrix within roller bit.The optimized interferences of teeth inserted into the bit can be reasonably obtained by the critical interference derived from some relevant influence factors on the tooth-fixing quality of roller bits.展开更多
Aeromagnetic interference could not be compensated effectively if the precision of parameters which are solved by the aircraft magnetic field model is low. In order to improve the compensation effect under this condit...Aeromagnetic interference could not be compensated effectively if the precision of parameters which are solved by the aircraft magnetic field model is low. In order to improve the compensation effect under this condition, a method based on small signal model and least mean square(LMS) algorithm is proposed. According to the method, the initial values of adaptive filter's weight vector are calculated with the solved model parameters through small signal model at first,then the small amount of direction cosine and its derivative are set as the input of the filter, and the small amount of the interference is set as the filter's expected vector. After that, the aircraft magnetic interference is compensated by LMS algorithm. Finally, the method is verified by simulation and experiment. The result shows that the compensation effect can be improved obviously by the LMS algorithm when original solved parameters have low precision. The method can further improve the compensation effect even if the solved parameters have high precision.展开更多
The phenomena of interference in the course of assembling curved bevel gears are ana. lysed and the corresponding prediction program of interference is established taking KlingInberg bevel gear as an exmple....The phenomena of interference in the course of assembling curved bevel gears are ana. lysed and the corresponding prediction program of interference is established taking KlingInberg bevel gear as an exmple. The factors influencing interferenee are discussed and the coneept ofcritical cutter radius is proposed. Finally, a simplified approximate function between the critical cutter ra- dius and the other factors is derived,and the designing method of avoiding interferenee is provided. The analysis and caiculation are proved to consistent with a case of actual product.展开更多
文摘The lifetime of roll-bits with inserted tooth will be obviously decreased while drilling in strata and the tungsten carbide can be integrally separated from the roll-cone,which will need more trip out time to replace the roller bit.This study provides an entire analysis on stress as well as strength for teeth and tooth holes in loaded conditions.Qualities of tooth drop from matrix within roller bit.The optimized interferences of teeth inserted into the bit can be reasonably obtained by the critical interference derived from some relevant influence factors on the tooth-fixing quality of roller bits.
基金co-supported by the National Basic Research Program of China (No. 623125020103)
文摘Aeromagnetic interference could not be compensated effectively if the precision of parameters which are solved by the aircraft magnetic field model is low. In order to improve the compensation effect under this condition, a method based on small signal model and least mean square(LMS) algorithm is proposed. According to the method, the initial values of adaptive filter's weight vector are calculated with the solved model parameters through small signal model at first,then the small amount of direction cosine and its derivative are set as the input of the filter, and the small amount of the interference is set as the filter's expected vector. After that, the aircraft magnetic interference is compensated by LMS algorithm. Finally, the method is verified by simulation and experiment. The result shows that the compensation effect can be improved obviously by the LMS algorithm when original solved parameters have low precision. The method can further improve the compensation effect even if the solved parameters have high precision.
文摘The phenomena of interference in the course of assembling curved bevel gears are ana. lysed and the corresponding prediction program of interference is established taking KlingInberg bevel gear as an exmple. The factors influencing interferenee are discussed and the coneept ofcritical cutter radius is proposed. Finally, a simplified approximate function between the critical cutter ra- dius and the other factors is derived,and the designing method of avoiding interferenee is provided. The analysis and caiculation are proved to consistent with a case of actual product.