Wang F.,Dalian University of Technology |
Sun J.,Dalian University of Technology |
Yan D.,Dalian University of Technology |
Zhang S.,Dalian University of Technology |
And 2 more authors.
Journal of Physics: Conference Series | Year: 2015
This paper discusses the fault feature selection using principal component analysis (PCA) for bearing faults classification. Multiple features selected from the time-frequency domain parameters of vibration signals are analyzed. First, calculate the time domain statistical features, such as root mean square and kurtosis; meanwhile, by Fourier transformation and Hilbert transformation, the frequency statistical features are extracted from the frequency spectrum. Then the PCA is used to reduce the dimension of feature vectors drawn from raw vibration signals, which can improve real time performance and accuracy of the fault diagnosis. Finally, a fuzzy C-means (FCM) model is established to implement the diagnosis of rolling bearing faults. Practical rolling bearing experiment data is used to verify the effectiveness of the proposed method.
Zhao Y.,Dalian University of Technology |
Ma H.,Dalian University of Technology |
Wang L.,Dalian University of Technology |
Sun C.,Dalian University of Technology |
Guo C.,West Pacific Petrochemical Co.
Acta Metallurgica Sinica (English Letters) | Year: 2011
A detailed knowledge of changes in microstructures and mechanical properties that occur in AISI 321 stainless steels service before and after solution treatment is of great interest, since the ductility and toughness of AISI 321 stainless steels may change drastically after service for a long time. After solution treatment at 1050 °C, the microstructures of AISI 321 stainless steels service for 80 000 h at 700 °C indicate that the content of sigma phase significantly decreased, the grains of austenite grew and the amount of twins together with the size increased with solution treatment time. The results of mechanical properties tests show that the impact toughness at room temperature was superior at solution treatment, and there was no obvious change in the impact toughness between different times of solution treatment at room temperature.
Liu C.,West Pacific Petrochemical Co. |
Zhang F.,West Pacific Petrochemical Co.
Petroleum Processing and Petrochemicals | Year: 2013
The scale formation mechanism in slurry system of RFCC unit was introduced and analyzed. It is found the slurry scale is composed of catalyst, coke and metal compound and originates from deposition of catalyst, coking in transfer line, coking at the bottom of fractionator and slurry cycling with the coking in transfer line as the main reason. Stabilizing the operation conditions of RFCC unit will inhibit scale in transfer line from entering slurry system. Adding anti-scale agent in slurry is also an effective way to slow down scale formation.
Xueqiang S.,North China Electrical Power University |
Yan B.,North China Electrical Power University |
Yuqiang D.,North China Electrical Power University |
Qing-Neng C.,West Pacific Petrochemical Company Ltd
Advanced Science Letters | Year: 2012
In view of the disadvantage that enterprises often adopt the subjective judgment of the experts to choose the equipments maintenance strategy, which is due to the lack of maintenance decision data in applications, a method based on fuzzy classifier is proposed here, that is using reliability and maintenance data in common database to construct the fuzzy classifier model, then classifying the production equipments of enterprises and choosing the optimal maintenance strategy according to different sorts. This method eliminates the disturbance from the factitious factors, enhances the practicability and validity of the maintenance strategy and procures favorable effect in applications. © 2012 American Scientific Publishers. All Rights Reserved.
Liu G.,West Pacific Petrochemical Co. |
Yu C.,West Pacific Petrochemical Co. |
Yang X.,West Pacific Petrochemical Co. |
Wang D.,CPECC East China Design Branch
Petroleum Processing and Petrochemicals | Year: 2010
Single stage reaction sequenced (SSRS) process developed by Chevron Lummus Global was introduced as the first industrial application case in the 1.5 Mt/a hydrocracking unit of Dalian West Pacific Petrochemical Company. With Chevron's ICR series catalysts and using Middle-East VGO as feedstock, the unit was operated under full recycle to obtain maximum middle distillats at a temperature range of 350-390 "C and a pressure of 14.6 MPa. The performance test results showed that with 100% conversion, the yield of middle distillates reached 83.1%: the smoke point of aviation fuel was 30 mm, the sulfur content of heavy diesel fraction was less than 10 μg/g and its cetane index was 61. Furthermore, the energy consumption of the unit was 61.3 MJ/t lower than the design data.
Qu Y.,West Pacific Petrochemical Company CO. |
Hao X.,West Pacific Petrochemical Company CO. |
Jiang A.,West Pacific Petrochemical Company CO. |
Gao M.,West Pacific Petrochemical Company CO.
American Society of Mechanical Engineers, Pressure Vessels and Piping Division (Publication) PVP | Year: 2010
The West Pacific Petrochemical Company Limited, Dalian is the first enterprise that adopts risk-based inspection (RBI) technology in the oil refinery plants in China, the application of RBI technology plays a positive role in guaranteeing long-cycle operation of the plant. With the continuous deepening of degree of understanding of API 581 standard and continuous enriching of experience with use of RBI software, by tracing the risks, there are three major factors that affect the risk of equipment or component, i.e. risk consequence, failure likelihood and management system, which are taken as the direction of efforts for guiding the implementation of equipment risk management measures. If there are litigation measures in the release consequence (sprinkler system or passive litigation technology) that can reduce continuous release rate and release time, then the release consequence of equipment can be reduced; if inspection techniques are adopted with respect to corrosion failure mechanisms or the proportion of inspection is increased in the failure likelihood, then the failure likelihood can be reduced effectively; and other measures such as analyzing the problems listed in each item of management system assessment and taking measures to improve management level and thus increase scores of management system by comparing the difference between the management of the enterprise itself and those listed in the standard. By implementing above measures, the ability of equipment risk management is improved and thus the intrinsic safety of equipment management is effectively guaranteed. Copyright © 2010 by ASME.
Zhu W.,West Pacific Petrochemical Co. |
Dong K.,West Pacific Petrochemical Co.
Petroleum Processing and Petrochemicals | Year: 2016
The problems of high H2S content in lean amine and in desulfurized gas in sulfur recovery plant of Dalian West Pacific Petrochemical Co. Ltd. were analyzed. It is found that the high amount of sodium ion (up to 7 800 μg/g) in amine solution is the key factor. The effective method to reduce Na+ from the amine solution, based on the lab experiment, is the on exchange technology. The hydrogen sulfide content in the lean amine solution of the industrial unit, after the on exchange treatment, is reduced from 4 g/L to 1. 5 g/L, and the desulphurization rate of the gases is improved significantly. The steam usage of the desufurization system decreases by 8 t/h.