Vibration Fault Analysis in Screw Compressor and Foundation

With the characteristics of low noise, low vibration, high reliability and long life, Screw Compressor is the indispensable main equipment which widely used in petrochemical field. The abnormal vibration of Compressor will affect normal operation of the host, lead to damage of some main parts such as Compressor and motor and at the same time it’s an unneglectable hidden trouble for equipment’s safe operation. This article takes the data acquisition of vibration and the analyses of shake for two Ammonia Refrigeration Piston Compressors, and study at the reason about shock then take the effective shockproof treatment plan. All these ensure the stable running of the facility.

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Health Monitoring on the Spacecraft Bearings in High-Speed Rotating Systems by Using the Clustering Fusion of Normal Acoustic Parameters

Applied Sciences ◽

10.3390/app9163246 ◽

2019 ◽

Vol 9 (16) ◽

pp. 3246 ◽

Cited By ~ 4

Author(s):

Wu ◽

Wang ◽

Liu ◽

He ◽

Xie

Keyword(s):

High Speed ◽

High Reliability ◽

Quality Parameters ◽

Normal Operation ◽

Acoustic Parameters ◽

Statistical Parameters ◽

Monitoring Method ◽

Practical Applications ◽

Rotating Systems ◽

Long Life

The rolling bearings in moment wheel assemblies (MWAs) or control moment gyros (CMGs) are not only the core components in spacecrafts but also prone to failure. Therefore, a high reliability is the critical characteristic for spacecraft bearings, and long-life testing on the ground is one of the main means for bearing reliability assessment. In practical applications, a convenient and reliable method is required for monitoring the health status of abnormal bearings in MWAs during the long-life test. In this paper, a monitoring method based on the clustering fusion of normal operation acoustic parameters is proposed for the identification of abnormal bearings. Firstly, the characteristics of MWA’s acoustic signal and its feasibility as a monitoring medium are clarified based on tests and modal analysis. Then statistical parameters and sound quality parameters are introduced to characterize the changes caused by bearing faults, and the root mean square (RMS), kurtosis, and sharpness parameters are selected to construct the feature vectors. The K-medoids clustering technology is used to fuse the characteristic parameters, and the safety distance for normal bearing operation can be obtained by a suitable method. Finally, the abnormal index is presented based on the excess rate and excess distance to judge the abnormal states of several types of bearings through tests. The research results indicate that the presented monitoring method based on the clustering of the normal operation acoustic parameters can not only identify various faults of the spacecraft bearing (ball defects, outer ring defects, cage instability, etc.) effectively but also give a quantitative evaluation of the severity of the abnormality.

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Research on Performance Test System of Space Harmonic Reducer in High Vacuum and Low Temperature Environment

Machines ◽

10.3390/machines9010001 ◽

2020 ◽

Vol 9 (1) ◽

pp. 1

Author(s):

Jing Wang ◽

Zhihua Wan ◽

Zhurong Dong ◽

Zhengguo Li

Keyword(s):

Low Temperature ◽

High Speed ◽

Performance Test ◽

High Reliability ◽

High Vacuum ◽

Test System ◽

Low Noise ◽

Speed Ratio ◽

Space Harmonic ◽

Temperature Environment

The harmonic reducer, with its advantages of high precision, low noise, light weight, and high speed ratio, has been widely used in aerospace solar wing deployment mechanisms, antenna pointing mechanisms, robot joints, and other precision transmission fields. Accurately predicting the performance of the harmonic reducer under various application conditions is of great significance to the high reliability and long life of the harmonic reducer. In this paper, a set of automatic harmonic reducer performance test systems is designed. By using the CANOpen bus interface to control the servo motor as the drive motor, through accurately controlling the motor speed and rotation angle, collecting the angle, torque, and current in real time, the life cycle test of space harmonic reducer was carried out in high vacuum and low temperature environment on the ground. Then, the collected data were automatically analyzed and calculated. The test data of the transmission accuracy, backlash, and transmission efficiency of the space harmonic reducer were obtained. It is proven by experiments that the performance data of the harmonic reducer in space work can be more accurately obtained by using the test system mentioned in this paper, which is convenient for further research on related lubricating materials.

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Tactile Interaction Sensor with Millimeter Sensing Acuity

Sensors ◽

10.3390/s21134274 ◽

2021 ◽

Vol 21 (13) ◽

pp. 4274

Author(s):

Eunsuk Choi ◽

Sunjin Kim ◽

Jinsil Gong ◽

Hyeonjeong Sun ◽

Minjin Kwon ◽

...

Keyword(s):

Shear Force ◽

High Reliability ◽

Normal Pressure ◽

Low Noise ◽

Sensing Material ◽

High Uniformity ◽

Tactile Interaction ◽

Force Direction ◽

Potential Applications ◽

Contact Shape

In this article we report on a 3 × 3 mm tactile interaction sensor that is able to simultaneously detect pressure level, pressure distribution, and shear force direction. The sensor consists of multiple mechanical switches under a conducting diaphragm. An external stimulus is measured by the deflection of the diaphragm and the arrangement of mechanical switches, resulting in low noise, high reliability, and high uniformity. Our sensor is able to detect tactile forces as small as ~50 mgf along with the direction of the shear force. It also distinguishes whether there is a normal pressure during slip motion. We also succeed in detecting the contact shape and the contact motion, demonstrating potential applications in robotics and remote input interfaces. Since our sensor has a simple structure and its function depends only on sensor dimensions, not on an active sensing material, in comparison with previous tactile sensors, our sensor shows high uniformity and reliability for an array-type integration.

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Practical long-life spark gaps for high-reliability applications

10.1109/modsym.1990.200983 ◽

2002 ◽

Cited By ~ 2

Author(s):

R.F. Caristi ◽

J.B. Roy ◽

R.L. Brooks ◽

A.J. Pennell

Keyword(s):

High Reliability ◽

Long Life

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Development of a new seismic-data acquisition station based on system-on-a-programmable-chip technology

Annals of Geophysics ◽

10.4401/ag-6309 ◽

2013 ◽

Vol 56 (3) ◽

Author(s):

Zhang Qi-sheng ◽

Deng Ming ◽

Guo Jian ◽

Luo Wei-bing ◽

Wang Qi ◽

...

Keyword(s):

Power Consumption ◽

Data Acquisition ◽

Digital Filter ◽

Data Transmission ◽

Seismic Data ◽

Low Noise ◽

High Definition ◽

Control Data ◽

Seismic Data Acquisition ◽

Transmission Speed

<p>There has been considerable development of seismic detectors over the last 80 years. However, there is still a need to further develop new earthquake exploration and data acquisition systems with high precision. In particular, for China to keep up with the latest technology of these systems, it is important to be involved in the research and development, instead of importing systems that soon fall behind the latest technology. In this study, the features of system-on-a-programmable-chip (SoPC) technology are analyzed and used to design a new digital seismic-data acquisition station. The hardware circuit of the station was developed, and the analog board and the main control data-transmission board were designed according to the needs of digital seismic-data acquisition stations. High-definition analog-to-digital converter sequential digital filter technology of the station (cascade integrator comb filter, finite impulse response digital filter) were incorporated to provide advantages to the acquisition station, such as high definition, large dynamic scope, and low noise. A specific data-transmission protocol was designed for the station, which ensured a transmission speed of 16 Mbps along a 55-m wire with low power consumption. Synchronic acquisition was researched and developed, so as to achieve accuracy better than 200 ns. The key technologies were integrated into the SoPC of the main control data-transmission board, so as to ensure high-resolution acquisition of the station, while improving the accuracy of the synchronic acquisition and data-transmission speed, lowering the power consumption, and preparing for the follow-up efforts to tape out.</p>

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POL and LDO for Harsh Environment Applications

Additional Conferences (Device Packaging HiTEC HiTEN & CICMT) ◽

10.4071/hiten-mp14 ◽

2013 ◽

Vol 2013 (HITEN) ◽

pp. 000075-000081

Author(s):

Ramesh Khanna ◽

Srinivasan Venkataraman

Keyword(s):

High Temperature ◽

Oil And Gas ◽

High Reliability ◽

Oil And Gas Industry ◽

Building Blocks ◽

Low Noise ◽

Harsh Environment ◽

Buck Converters ◽

Gas Industry ◽

Component Selection

Harsh Environment approved components/ designs require high reliability as well as availability of power to meet their system needs. The paper will explore the various design constrains imposed on the high temperature designs. Down hole oil and gas industry requires high reliability components that can withstand high temperature. Discrete component selection, packaging and constrains imposed by various specification requirements to meet harsh environment approval are critical aspect of high-temp designs. High temperature PCB material, PCB layout techniques, trace characteristics are an important aspect of high-temperature PCB design and will be explored in the article. Buck Converters are the basic building blocks, but in order to meet system requirements to power FPGA's where low output voltage and high currents are required. Converter must be able to provide wider step down ratios with high transient response so buck converters are used. The paper with explore the various features of a buck-based POL converter design. Low noise forces the need for Low-dropout (LDO) Regulators that can operate at high Temperatures up to 210°C. This paper will address the power requirements to meet system needs.

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PROGRESS AND OUTLOOK ON FEW COMPONENT COMPOSITE SOLID STATE ELECTROLYTES

MRS Advances ◽

10.1557/adv.2019.264 ◽

2019 ◽

Vol 4 (49) ◽

pp. 2635-2640

Author(s):

Chavis A. Stackhouse ◽

Alyson Abraham ◽

Kenneth J. Takeuchi ◽

Esther S. Takeuchi ◽

Amy C. Marschilok

Keyword(s):

Solid State ◽

Recent Progress ◽

High Reliability ◽

High Energy ◽

High Energy Density ◽

Composite Electrolytes ◽

Manufacturing Costs ◽

Solid State Batteries ◽

Long Life ◽

Composite Solid

ABSTRACTLithium solid-state composite electrolytes (LiSCEs) provide the opportunity for long life spans, low self-discharge, high reliability, high energy density, and safety. Additionally, this class of electrolytes can be used in electrolytically formed solid-state batteries (EFBs), which may promote reductions in cell manufacturing costs due to their simplicity of design and permit the formation of batteries with diverse architectures. Herein, we provide a discussion of LiSCEs, highlight some of the recent progress in EFB development, and present a forward outlook.

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Design of Flammable Gas Monitoring Circuit Based on TGS813

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.479-481.2246 ◽

2012 ◽

Vol 479-481 ◽

pp. 2246-2249

Author(s):

Cui Zhi Chang

Keyword(s):

Data Acquisition ◽

Gas Sensor ◽

Gas Monitoring ◽

Flammable Gas ◽

Long Life

In this paper, a flammable gas monitoring circuit is designed based on TGS813 that is a flammable gas sensor and has the characteristic of long life-pan, low prices. The principle and structure of TGS813 are introduced as well as applied in multi-channel data acquisition circuit.

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