Transducer for measuring the rotation speed of a shaft

Conclusions The design of the proposed transducer is very simple; it consists of a few components and is simple to manufacture and assemble. It can be made a fraction of the size of the smallest tachogenerator type TGP-3. The power consumed by it is insignificant. Its coupling to the shaft of the object under investigation produces virtually no effect on the operating conditions of the latter. Translated from Izmeritel'naya Tekhnika, No. 11, pp. 22–23, November, 1961     

传动轴扭矩测量装置的结构设计及实验分析

为解决传动轴扭矩难以实现长期监测的问题,设计一种新型传动轴扭矩测量装置.在传动轴表面焊接一底座,用紧固螺栓把扭矩测量装置固定在上面,通过测量敏感梁的应变测出所受扭矩.对自制的实验扭矩测量装置利用ANSYS Workbench进行静力学分析,同时进行静态特性和动态响应实验,得出特性指标和响应曲线,实验结果证明:该扭矩测量装置可行有效,对解决传动轴扭矩的监测具有实际指导意义.     

Determining the direction of rotation of a shaft

Translated from Izmeritel'naya Tekhnika, No. 8, p. 47, August, 1992.     

Failure analysis of a hydraulic Kaplan turbine shaft

This paper shows the results of the failure analysis of a 105 MW Kaplan turbine auxiliary shaft from a hydropower plant. As a part of the failure analysis, the turbine operation history was revised and the metallographic study was done. A sample of the cracked turbine shaft was examined using optical microscopy and scanning electron microscopy. Failed auxiliary shaft was coupled to the main turbine shaft and its principal function was turning the runner blades according to flow direction. In order to complement the cause of failure, a finite element analysis (FEA) was done to calculate the stress level under the maximum and minimum turbine blade inclination position. The results of present investigation showed that failure was caused by high cycle and low stress fatigue. The presence of a stress concentrator on the turbine shaft was a crucial factor to the fatigue crack-initiation phase. The FEA revealed also that the frequently load variations, showed in the operation history, could have contributed to the crack propagation.     

Diosna P25 high-speed mixer equipped with instruments for measuring the rate of rotation of the main impeller motor shaft

An optical incremental encoder, combined with suitable electronic equipment of an analogue or digital type, proved to be a very sensitive instrument for obtaining measurements of the rate of rotation of the main impeller shaft.

The high sensitivity of the equipment could not be fully exploited, as the mains voltage fluctuation and the heat effects on the gear box caused some uncertainties in the measuring. When lactose was granulated with gelatin solution, impeller and chopper working at a high speed, the uncertainties were approximately ±1-2%.     

Diosna P25 high-speed mixer equipped with instruments for measuring the rate of rotation of the main impeller motor shaft

Abstract

An optical incremental encoder, combined with suitable electronic equipment of an analogue or digital type, proved to be a very sensitive instrument for obtaining measurements of the rate of rotation of the main impeller shaft.

The high sensitivity of the equipment could not be fully exploited, as the mains voltage fluctuation and the heat effects on the gear box caused some uncertainties in the measuring. When lactose was granulated with gelatin solution, impeller and chopper working at a high speed, the uncertainties were approximately ±1–2%.     

Fracture analysis of wind turbine main shaft

Shaft fracture at an early stage of operation is a common problem for a certain type of wind turbine. To determine the cause of shaft failure a series of experimental tests were conducted to evaluate the chemical composition and mechanical properties. A detail analysis involving macroscopic feature and microstructure analysis of the material of the shaft was also performed to have an in depth knowledge of the cause of fracture. The experimental tests and analysis results show that there are no significant differences in the material property of the main shaft when comparing it with the Standard, EN10083-3:2006. The results show that stress concentration on the shaft surface close to the critical section of the shaft due to rubbing of the annular ring and coupled with high stress concentration caused by the change of inner diameter of the main shaft are the main reasons that result in fracture of the main shaft. In addition, inhomogeneity of the main shaft micro-structure also accelerates up the fracture process of the main shaft. In addition, the theoretical calculation of equivalent stress at the end of the shaft was performed, which demonstrate that cracks can easily occur under the action of impact loads. The contribution of this paper is to provide a reference in fracture analysis of similar main shaft of wind turbines.     

Optical method for measuring optical rotation angle and refractive index of chiral solution

Based on the phenomena of Brewster's angle and the principles of common-path heterodyne interferometry, we present an optical method for measuring the optical rotation angle and the refractive index of a chiral solution simultaneously in one optical configuration. A heterodyne light beam and a circularly polarized heterodyne light beam are separately guided to project onto the interface of a semicircle glass and a chiral solution. One of the beams is transmitted through the solution, and the other is reflected near Brewster's angle at the interface. Then the two beams pass through polarization components respectively for interference. The phase differences of the two interference signals used to determine the rotation angle and the refractive index become very high with the proper azimuth angles of some polarization components, hence achieving an accurate rotational angle and a refractive index. The feasibility of the measuring method was demonstrated by our experimental results. This method should bear the merits of high accuracy, short sample medium length, and simpler operational endeavor.     

用89C51单片机实现的一种新型低速转速测量方法

介绍了用 89C5 1单片机实施低速转速 (n≤ 10 0 r/ s)的测量方法 ,如何利用测速齿轮和磁性探头组成的转速变送器的工作原理、特点及测速齿轮的齿数不是标准 Z=6 0齿数的编程算法 .论述了测量系统的硬件构成与软件设计的框图