Test stand for certification of radiation receivers

Translated from Izmeritel'naya Tekhnika, No. 6, pp. 37–38, June, 1990.     

Automated fatigue testing stand

Design principles, structure, and operating features of a stand with extended functional possibilities for laboratory fatigue tests are examined. With a highly reliable protection system, the stand facilitates detection of the instant at which a damage originates in the tested object and recording of the process of its development from start to complete failure.Translated from Problemy Prochnosti, No. 8, pp. 104–107, August, 1990.     

A tuning fork vibration stand

Summary The described tuning fork vibration stand provides the possibility of dynamic calibrations of accelerometer transducers and indicators, and also of checking the operational capabilities of components and their combinations of small weight under vibrational accelerations reaching 500 g's at fixed, predetermined frequencies.     

Imperfections in tree stand failures

Analyses of two climbing tree stand accidents are presented to show that serious imperfections in the chains would not have produced the failures had the tree stands been used within rated capacity. Stress analysis and tests demonstrated that roller chain with cracked links could operate at rated capacity without further crack growth and showed that loads approximately three times rated capacity were required to cause the pullout of an improperly staked pin. Although the chains in the tree stands involved in both accidents had serious imperfections, the imperfections did not produce a failure of the product within the rated capacity of the tree stands. However, operating conditions in excess of the rated capacity exposed the imperfections and led to the failures. Neither imperfection should have been considered a defect because they did not reduce the capacity of the tree stands below the rated capacity.     

Universal stand for testing roller-vane flowmeters

Universal stand SUZhG-1, of class 0.02, has been developed, tested, and certified. The stand can be used to test and calibrate master high-precision wide-range roller-vane flowmeters for liquids and gases, as well as other types of flowmeters and quantity meters. Highly accurate methods of testing and calibrating instruments have also been developed and introduced. Translated from Izmeritel'naya Tekhnika, No.4 pp. 57–60, April, 2000.     

Failure analysis of rolling mill stand coupling

The failure analysis of two slipper couplings showed that both couplings fractured as a result of fatigue. In both cases, the fracture started in the corner between the paddle and the coupling body and propagated around the corner. Both fractures are caused by deficient design of the fillet between the paddle and the coupling body with high stress concentration. In order to extend actual service life, three design modifications have been considered. Numerical analysis showed that redesign of coupling by stiffener between the paddle and the coupling body reduces maximum local and actual service life of couplings can be improved from finite to infinite.     

水泥胶砂抗压强度不确定度的分析与计算

在建筑材料的检测中,检测标准只对检测的变异系数有要求,单个检测单位的变异系数只能表征偶然因素对检测结果准确度的影响,而不能使检测人员和用户确切获知检测结果和被检对象的真值之间可能的最大误差,检测结果不确定度的引入,可以解决对检测结果的准确度不能直接定量表示的难题。本文对水泥胶砂抗压强度不确定度的来源、计算和合成等进行了阐述,可以作为建材检测单位确定其他检测项目不确定度的借鉴。     

Investigation of the piezoelectric thrust test stand for rocket engine

Based on the piezoelectric effect, a new type of piezoelectric thrust vector-measuring system for a rocket engine is designed, which is made up of four three-component piezoelectric force sensors, so that 12 output force signals can be generated. Using the theoretical mechanics, the reverse formulas for the thrust vector (namely, the misalignment angle and the offset) are deduced. In order to calibrate the measuring system, a special calibration platform is designed. The calibration results show that the non-linearity and cross talk of the designed piezoelectric thrust vector-measuring system are less than 1 and 5%, respectively. Finally, a practical loading experiment is performed to test the application performance of the thrust vectormeasuring system, and the experimental results prove that the thrust vector-measuring system can accurately measure both the magnitude and the direction of the thrust vector.     

某火箭试验台低温甲烷排放过程数值模拟

以低温甲烷安全排放为目的,采用数值模拟方法对某试验台甲烷高空排放系统进行研究,分别采用AMESim软件及Fluent软件对排放管内的流动和管外的扩散情况进行了分析,安全排放准则为甲烷云团向上飘动或者水平扩散,研究工况包括了长期稳定排放及大流量短期排放。计算结果表明:排放流量越小越安全,长期稳定排放时甲烷的最大排放流量不能超过75g/s;试验台常规排放流量200 g/s最长的排放时间不得超过300 s,最长排放时间随着排放流量的增加而减小。     

Versatile table-top test stand for pressure-testing equipment components and sensing elements

Conclusions Tests conducted with laboratory standard devices have provided a positive evaluation of the significant characteristics of the new test stand, namely: the self-sealing design of the hermetic seals on the upper and lower openings of the pressure chamber, thereby obviating special efforts to achieve perfect seals, and the possibility of calibration techniques without using liquids, by employing the manual screw press and compressed air (from an in-plant system or from a tank). This test stand has made it possible to significantly expand the scope of application of a variety of components and sensing elements which must operate under elevated pressures.Translated from Izmeritel'naya Tekhnika, No. 11, pp. 104–105, November, 1970.