Latest ArticlesAiming at the non-stationary characteristics of early failure vibration signal of gear and the fact that it is seriously affected by environmental noise and the fault feature is weak so it is hard to be extracted, the ensemble local mean decomposition is used to decompose the fault vibration signal of gear to obtain the product function of finite single component, so as to highlight the local characteristics of the signal. However, because of the noise interference, it is difficult to extract the fault feature frequency information from frequency spectrum of each component, and based on that, in the paper, the fault diagnosis method of ensemble local mean decomposition and minimum entropy deconvolution is proposed. Through the analysis of gear fault simulation experiment and project case, fault characteristic information of gear can be extracted accurately and effectively, which provides a new method for practical engineering application.
In the paper, thermodynamic calculation of yttrium zinc alloy prepared by electrolytic oxide in fluoride molten salt system is carried out. The decomposition voltage of Y2O3 + 3C = 2Y + 3CO is 1.4 V at 1 027 ℃; through the phase diagram analysis of LiF-YF3 and Y-Zn two element system, it is known that electrolyte of (25%~100%) LiF-(75%~0%) YF3(mass fraction) is molten state at 1 027 ℃, yttrium zinc alloy with the 20%~30% (mass fraction) zinc content is molten state; The analysis of alloy density shows that the density of yttrium zinc alloy>4.469 g/cm3, which is larger than the density of electrolyte.
At present, the separation of rare earth elements by solvent extraction method in P507 hydrochloric acid system, in order to stabilize the quality of two export product in the extraction production line, and make up for the defects caused by the lag of analysis results. On the basis of production practice, the paper makes an effective improvement on the control process, and analyzes and discusses the process of technology improvement, improvement measures and effects.
The electric control system of bridge crane adopts dedicated G7 frequency converter to control, so it can realize stepless speed regulation easily. The speed control range is wide; the speed regulation precision is higher; the speed response time is quick; the torque at starting and low speed running is big and has S parameter setting for special hoist, so that hoisting motor can provide larger rated torque output at zero speed, prevent hoisting mechanism from generating hook gliding phenomenon and improve the safety in the use of crane.
Modbus protocol is a common language used in the electronic controller. Through this protocol, the controller can communicate with each other through the network and other devices. The paper describes the network communication between S7-300 PLC and third party device through the CP341 module, gives the specific communication protocol, technical solutions for the problem, and some examples of the implementation code.
In the paper, it is introduced the practical significance of furnace pressure control for continuous heating furnace in production control of heating furnace, and the detection method and control method of furnace pressure for heating furnace. Because the furnace door often switches, it will cause frequent furnace pressure fluctuation, however, the normal PID regulating mode has weak anti-jamming capability, and it is easy to occur oscillation when the measurement value changes frequently, so it can not be effectively controlled. Fuzzy control has the characteristics of fast convergence, small overshoot and strong anti-jamming capability, and is most suitable for controlling the furnace pressure.
The paper uses chekland methodology, based on study of mine geological work management contents, constructs the conceptual model of mine management; based on the comparison between conceptual model and actual situation, the paper analyzes and summarizes the main problems existing in the mine and draws the methods and measures that can effectively strengthen the mine geological management.
In the paper, it is introduced the planning and implementation of mobile informatization construction for iron and steel enterprise. Based on the mobile informatization project development and function of WeChat enterprise number, mobile informatization application which based on WeChat enterprise number for large iron and steel enterprise is constructed and it provides convenient mobile information searching and business processing for employees of Baotou Steel (Group) Corporation. So far, it has more than thirty thousand registered users following the WeChat enterprise number.
The quality of librarians determines the development level of a library. Based on the status analysis of the quality of librarians in higher vocational colleges in our country, in the paper, it is discussed the connotation and necessity of continuing education for librarians, and puts forward some methods and ways on how to improve the quality of librarians, how to serve the readers and teach better.
In the paper, the factors that affect the temperature drop of molten iron in torpedo car, such as the charge weight of molten iron, the thickness of brick lining for torpedo ladle, the operating time of empty tank and heavy tank that are analyzed through living examples. Measures have been put forward to reduce the temperature drop through which the temperature drop rate of molten iron in torpedo ladle can be effectively controlled proved by practice.
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