Advanced Materials Research Vols. 605-607

Abstract: Used the high order spectrum and slice analysis method, studied the elevator running vibration acceleration signals and calculated the trispectrum two dimensional slices, bispectrum and theirs diagonal slices, under different running conditions. The results show that: when the elevator normal operation the acceleration signal spectrum peaks concentration, otherwise the acceleration signal peaks dispersion; in fault condition, compared to bispectrum peaks trispectrum peaks is sharper. High order spectrum contains abundant information of different fault elevator running details. It is a suitable analysis tool for diagnosing the faults of elevator.

Abstract: Avoiding well collision has become an increasingly critical challenge for the drilling industry in recent years. The wellbore Anti-collision Monitoring system is developed because the vibrations caused by an approaching drill bit can be monitored from the existing well casing and used to pre-alarm the wellbore collision. By analyzing the time-domain signal collected by the system in different drilling conditions, the influences of the drilling parameters (RPM and WOB) on drill bit signal are identified; and by analyzing the frequency-domain signal, the characteristic frequency range (200-400Hz) of the drill bit signal is determined. When the drill bit is approaching to the adjacent well, the reconstruction bit signal after band-pass filter changes significantly and agrees well with the on-site situation. The field test results show that the monitoring system is effective and provides a new way to the anti-collision techniques.

Abstract: For a long time, the monitor and maintain of navy Vessels equipment is based on the traditional maintain theories and plan maintain. But with the development of electronical and digitization, this kind of traditional mode is more and more hard to satisfy the maintaining need of Vessels equipment, and restrict the formation and exaltation of troops fighting strength. Currently the technologies of fault prognostics and integrated health management are becoming regarded, especially on many Vessels equipment systems. The information about abnormal situation of Vessels equipment was received and estimated by fault diagnosis and prognostic module. The diagnostic and prognostic results were supplied to the analysis and decision module to make the conclusion. The paper talks about the structure and function of the prognostic and health system, which is for certain kind of Vessels equipment.

Abstract: With respect to the failure of drive shaft of a large pendulum, a finite element software is used to analyze its stress. The results indicate that the failure is caused by inadequate design of the fatigue strength of the output shaft. Chamfer is the main reason for changing the fatigue strength safety factor, in addition, the drive system may also cause the stress of output shaft too large. At last, specific equipment improvements and shaft failure countermeasures is put forward.

Abstract: In this paper, a new method on quantitative analysis of magnetic flux leakage signal by ant colony neural network is proposed. Firstly, the parameters of the magnetic flux leakage signal which can reflect the various characteristics of cracked defects are determined by finite element method (FEM) simulation. Secondly, based on the study of the ant colony algorithm, the neural network model is established for the magnetic flux leakage signals processing. Finally, in the simulated working environment, the performance of the neural network is tested with the different signal features as input. The experimental results proved the feasibility of the ant colony neural network, verified the increases of the convergence rate and the accuracy of the neural network, and improved the efficiency as well as the quality of the quantitative analysis for the magnetic flux leakage signals.

Abstract: According to the working principle of reciprocating compressor valves, combined with the actual operation, analyze the reliability of the compressor valves and valve failure phenomenon, and raise ways to improve the reliability of the valve.

Abstract: In the case of zero-failure data, we get the new estimation formula about the reliability of double-parameter distribution by using a new modified maximum likelihood estimation method and Bayesian estimation method.Finally calculation is performed concerning practical problem.

Abstract: The large amounts of data will be produced through the measurement in the gun maintenance process. So the performance of the measurement system will directly affect the quality of the data and the gun maintenance. Based on the situation, the application of measurement system analysis in controlling the gun maintenance quality was studied. Taking the measurement of the gun recuperator fluid amount for an example, the calculator of the gun fluid amount was analyzed. The result showed that it could effectively improve the quality to use the measurement system analysis in controlling the gun maintenance process.

Abstract: A kind of selection method of parameter distribution is proposed to solve the distributive parameter selection problem of packet data by using common Turnbull estimated curve as a standard curve. This method can meet the requirements of data distributive selection for data analysis such as reliability assessment, and it can guide the engineering and technical researchers to choose a reasonable fitting of the data distribution, and to improve the accuracy and efficiency of reliability assessment

Abstract: Temperature and thermo-mechanical coupling stress distributions of the electrical three-way valve body in a high pressure heater are investigated by using finite element method analysis. Maximum stress at the outer wall region of the valve body has exceed the allowable stress of the material is obtained. The weak place is improved by increasing the wall thickness and the stress meet the requirement of the allowable stress of the material after FEM analysis. And the thermo-mechanical coupling stress are classified and evaluated in the most dangerous section. The evaluation results show that the various types of stress all meet intensity requirements, which provide a guideline for the design and optimization of the high temperature and high pressure valve in the future.