Condition monitoring for the safe operation of offshore cranes

2016 ◽  
Vol 56 (2) ◽  
pp. 605
Author(s):  
Julio De Melo ◽  
Luis Rojas ◽  
Daniel Shorten
Keyword(s):  
Early Detection ◽  
Condition Monitoring ◽  
Structural Integrity ◽  
Monitoring Program ◽  
Safe Operation ◽  
Operating Life ◽  
Visual Appearance ◽  
Bearing Condition Monitoring ◽  
Key Factor ◽  
Hidden Failures

Offshore cranes work in harsher conditions than their onshore counterparts, with exposure to a highly corrosive environment and dynamic loading when conducting lifts from floating vessels. These degradation mechanisms can significantly reduce equipment life expectancy and increase maintenance/replacement costs without adequate mitigation programs in place. A systematic process must be followed to identify the potential for loss of integrity of components that could lead to failure, and strategies should be defined/implemented to ensure safe operation. Study outcomes feed into the maintenance and sparing philosophy, and cascade to site personnel as maintenance and operating procedures. The implementation of a robust condition-monitoring program prior to degradation occurring is a key factor in the success of this program, examples of which include the following. Slew bearing condition monitoring: in addition to regular visual inspection and recording of measurable readings, a well-structured grease sampling and analysis protocol provides early detection of moisture ingress, deterioration of lubrication and bearing failure. Structural integrity: reporting on integrity by exception does not provide confidence that an area may have been left out, or consistency in ongoing reporting. End of useful life definition: some components aren’t available for inspection; others can be inspected however they are susceptible to failures that are not practically detectable. These potential hidden failures can be prevented if a process is followed where the critical component’s operating life is defined, with appropriate supporting justification, and it is renewed accordingly regardless of visual appearance. An effective condition-monitoring program allows the operator to ascertain if the strategies in place are effective, pick up early detection of potential failure, and arrest the degradation while still inside a safe operating envelope.

Development of Prognostic Techniques for Surface Defect Growth in Railroad Bearing Rolling Elements

2017 ◽  
Author(s):  
Nancy De Los Santos ◽  
Robert Jones ◽  
Constantine M. Tarawneh ◽  
Arturo Fuentes ◽  
Anthony Villarreal
Keyword(s):  
Growth Rate ◽  
Early Detection ◽  
Condition Monitoring ◽  
Surface Defect ◽  
Full Load ◽  
Defect Growth ◽  
Bearing Condition Monitoring ◽  
Full Load Operation ◽  
Railroad Bearing ◽  
The University

Prevention of bearing failures which may lead to catastrophic derailment is a major safety concern for the railroad industry. Advances in bearing condition monitoring hold the promise of early detection of bearing defects, which will improve system reliability by permitting early replacement of failing components. However, to minimize disruption to operations while providing the maximum level of accident prevention that early detection affords, it will be necessary to understand the defect growth process and try to quantify the growth speed to permit economical, non-disruptive replacement of failing components rather than relying on immediate removal upon detection. The study presented here investigates the correlation between the rate of surface defect (i.e. spall) growth per mile of full-load operation and the size of the defects. The data used for this study was acquired from defective bearings that were run under various load and speed conditions utilizing specialized railroad bearing dynamic test rigs operated by the University Transportation Center for Railway Safety (UTCRS) at the University of Texas Rio Grande Valley (UTRGV). Periodic removal and disassembly of the railroad bearings was carried out for inspection and defect size measurement and documentation. Castings were made of spalls using low-melting, zero shrinkage Bismuth-based alloys so that a permanent record of the full spall geometry could be retained. Spalls were measured using optical techniques coupled with digital image analysis and also with a manual coordinate measuring instrument with the resulting field of points manipulated in MatLab™ and Solidworks™. The spall growth rate in area per mile of full-load operation was determined and, when plotted versus spall area, clear trends emerge. Initial spall size is randomly distributed as it depends on originating defect depth, size, and location on the rolling raceway. The growth of surface spalls is characterized by two growth regimes with an initial slower growth rate which then accelerates when spalls reach a critical size. Scatter is significant but upper and lower bounds for spall growth rates are proposed and the critical dimension for transition to rapid spall growth is estimated. The main result of this study is a preliminary model for spall growth which can be coupled to bearing condition monitoring tools to permit economical scheduling of bearing replacement after the initial detection of spalls.

Innovative Upgrading of Heritage Buildings: Structural Case Studies

2018 ◽  
Author(s):  
Kribanandan Gurusamy Naidu
Keyword(s):  
Case Studies ◽  
Structural Integrity ◽  
Adaptive Reuse ◽  
Urban Spaces ◽  
Masonry Buildings ◽  
Fair Share ◽  
Visual Appearance ◽  
Heritage Buildings ◽  
Proper Design ◽  
Structural Case

<p>The challenge of integrating old and new in the development of urban spaces is constrained by commercial realities and an ignorance of the value of maintaining historical relevance as society develops. Malaysia has had its fair share of such historical gems being destroyed without much consideration for heritage but there also exists significant projects where proper design and engineering have been applied for conservation and adaptive reuse.</p><p>In this paper innovative options for structural upgrading of masonry buildings is considered using techniques which provide a basis for achieving structural integrity without compromising the visual appearance and historical value. This includes examples of a shop house upgraded following significant settlement due to adjacent construction and an adaptive reuse of a school which was converted into a theatre.</p>

Rolling Element Bearing Condition Monitoring and Diagnosis

2010 ◽  
Vol 34-35 ◽  
pp. 332-337
Author(s):  
Hui Bin Lin ◽  
Kang Ding
Keyword(s):  
Condition Monitoring ◽  
Rolling Element Bearing ◽  
Bearing Fault ◽  
Monitoring And Diagnosis ◽  
Bearing Condition Monitoring ◽  
Envelope Detection ◽  
Rolling Element ◽  
Machine Speed ◽  
Bearing Characteristic ◽  
The Impact

Bearing failure is one of the foremost causes of breakdown in rotating machinery. To date, Envelope detection is always used to identify faults occurring at the Bearing Characteristic Frequencies (BCF). However, because the impact vibration generated by a bearing fault has relatively low energy, it is often overwhelmed by background noise and difficult to identify. Combined the results of extensive experiments performed in a series of bearings with artificial damage, this research investigates the effect of many influencing factors, such as demodulation methods, sampling frequency, variable machine speed and the signals collected in different directions, on the effectiveness of demodulation and the implications for bearing fault detection. By understanding these effects, a more skillful application of the envelope detection in condition monitoring and diagnosis is achieved.

scholarly journals Bureaucratic Reform in the Empirical Perspective and Pathology

2019 ◽  
Vol 3 (2) ◽  
pp. 1-14
Author(s):  
Diah Anggraeni
Keyword(s):  
Sustainable Development ◽  
Services Quality ◽  
Monitoring Program ◽  
Personal Interest ◽  
Main Program ◽  
Improvement Program ◽  
Government Organizations ◽  
Key Factor ◽  
Empirical Perspective ◽  
Bureaucratic Reform

Bureaucracy in government organizations is a key factor in the implementation of dailyadministration tasks. The division of labor, authority and responsibility and supervision,will be evident in the structure of this organization. Errors in the preparation of thestructure will be able to lead the implementation of the task can not be run efficiently andeffectively, and may even lead to errors in the performance of duties. And these errorsare related to the attitude of the bureaucrats’ condition urgent reforms. Wisdom Reformsto be implemented need to be identified on the substance of wisdom in it that includesnine (9) main program (Ministry of PAN-RB, 2010b: 22-26), namely: Change ManagementProgram; Setup program legislation; Organization Structuring and ReinforcementProgram; Setup Program Management; System Setup program in Human ResourceManagement Apparatus; Strengthening Monitoring Program; Strengthening ProgramPerformance Accountability; Public Services Quality Improvement Program; ProgramMonitoring, Evaluation and Reporting related to the reform of the bureaucracy tends tochange the bureaucratic standard. Pathology is a perception that attitudes, behaviors,and as a tendency to respond to a person’s soul something that is operationalized throughbehavior. Behavior will affect the commitment and dedication of personnel in performanceof its duties, especially in service to the community. In this case, which is an indicator ofthe attitude dimensions executor is a personal interest, affection for the organization, andforesight.Key Words: Bureaucracy Reform, Bureaucracy Pathology, Sustainable Development.

The Characterization and Conservation of Aged Aluminum Alloys: Buckminster Fuller's Dymaxion House

2002 ◽  
Vol 712 ◽  
Author(s):  
Karen A. Trentelman ◽  
James Ashby ◽  
William T. Donlon
Keyword(s):  
Aluminum Alloys ◽  
Structural Integrity ◽  
Primary Aluminum ◽  
Grain Structure ◽  
Age Hardening ◽  
Original Structure ◽  
Visual Appearance ◽  
Henry Ford ◽  
Buckminster Fuller ◽  
Cladding Layers

ABSTRACTThe Dymaxion House is a unique historic dwelling structure designed by Buckminster Fuller. Built in the 1940s, the house was constructed of modern materials, most notably aluminum, which formed the walls, roof and many of the structural elements. The challenge faced in reconstructing the Dymaxion House at Henry Ford Museum & Greenfield Village was to preserve the original structure as much as possible while simultaneously accommodating the needs of exhibition (i.e. to restore the visual appearance and ensure sufficient structural integrity to allow the entrance of visitors). The primary aluminum alloys used in the house are equivalent to the modern alloy designations 2014 and 2024; both extruded forms and Alclad sheets were used. The alloy composition, age-hardening characteristics, cladding layers, grain structure and corrosion products of the aged aluminum components of the Dymaxion House have been studied. The results of these studies were used in consultation with conservators, engineers and corrosion scientists to determine the most appropriate course of treatment.

Bearing Scuffing Detection and Condition Monitoring Using Virtual Instrumentation

2014 ◽  
Vol 657 ◽  
pp. 604-608 ◽  
Author(s):  
Carmen Bujoreanu ◽  
Florin Breabăn
Keyword(s):  
Condition Monitoring ◽  
Virtual Instrument ◽  
Friction Torque ◽  
Diagnostic Methods ◽  
Virtual Instrumentation ◽  
Friction Forces ◽  
Data Acquisition Board ◽  
Bearing Condition Monitoring ◽  
Braking Torque ◽  
Vibration Signature

Bearing condition monitoring confronts the most machine users. Diagnostic methods used to include bearing problems represent one of the most important challenges. The scuffing phenomenon initiation of the bearing elements produces an important increase in the vibration level and can be emphasized by the analysis of the bearing friction forces which are the most sensitive indicator of the bearing failure. Commonly used technique for damage detection is the vibration signature analysis that must be carefully utilized in conjunction with the friction torque monitoring through the strain gauges measurements. In order to detect the scuffing onset, the paper presents an experimental setup for the scuffing tests performed on a 7206 ball bearing. A virtual instrument monitoring the friction force respectively the braking torque was created. An accelerometer captures the signal from the bearing outer ring then it is processed using PCI-4451 National Instruments data acquisition board and LabVIEW soft.

Ultrasound and Nonlinear Resonant Testing of Nuclear Reactor Internals Bolts

2011 ◽  
Author(s):  
S. W. Glass ◽  
B. Thigpen ◽  
J. Renshaw
Keyword(s):  
Phased Array ◽  
Nuclear Reactor ◽  
Structural Integrity ◽  
Cost Effective ◽  
Life Extension ◽  
Safe Operation ◽  
Plant Life ◽  
Nuclear Plants ◽  
Bolt Failure ◽  
Reactor Internals

As many nuclear plants approach the end of their initial 40 year license period, inspection or replacement of their reactor internals bolts must be considered. This is consistent with the Materials Reliability Program (MRP 227/228) guideline for plant life extension [1,2]. Assurance of the internals structural integrity is essential for continued safe operation of these plants. If there is no suspicion or indication of bolt failure, simple inspection is normally more cost-effective than replacement. Inspection vendors have inspected thousands of internals bolts with conventional and Phased Array UT but different head configurations and bolt capture mechanisms mandate specific qualifications for each bolt type. In some cases, complex bolt and head geometries coupled with counter-bore and locking bar interferences render classical UT inspections difficult or impossible. A range of solutions to inspect reactor internals including these difficult-to-inspect-by-conventional-UT baffle bolts has been developed by several vendors [3]. This presentation references developments to make bolt inspection a relatively quick and easy task through adaptations to the SUSI submarine inspection platform, the extensive UT qualification work suitable for conventional UT plus more recent advanced nonlinear resonant techniques to distinguish between flawed or loose, vs. acceptable bolts where conventional UT cannot be applied. Initial evaluations show that these advanced techniques may have the ability to reliably detect smaller flaws than previously possible with conventional techniques as well as provide information on bolt tightness.

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