Condition Monitoring/Predictive Maintenance

FAQ – Issues of High Distortion Surrounding VFDs

whitelegg pic 4by Ernesto Wiedenbrug, Ph.D.
Variable Frequency Drives (VFDs) can introduce power quality problems to line-operated motors on the same buss, and also to the motors being driven by VFDs. This FAQ shows typical voltage and current waveforms for such systems, and touches upon some of the potential power quality problems.
To continue reading the full case study, with images, please download the free PDF file here.  
http://csaanalysis.com/PDFS/FAQ%20-%20Issues%20of%20High%20Distortion%20surrounding%20VFDs.pdf
To contact Whitelegg direct please visit http://www.whitelegg.com  

Advanced Rotorbar Analysis – False Positives: Spiders / Axial Cooling Vents

whitelegg pic 3Ernesto Wiedenbrug, Ph.D., SM IEEE,
Virtually all rotors of motors above 100kW are designed with axial  cooling vents, potentially causing false positives for both prevalent  diagnostic technologies, vibration and MCSA. Fig 1 shows the rotor  with 8 spider-legs of a 2.4MW 6.6kV motor that was pulled out of  service due to such a vibration and MCSA false positive.
 This paper explains how to recognize problematic motors, the reason for these false positives, how these motors react, and how  to deal with them.
To continue reading the full case study, with images, please download the free PDF file here.  http://csaanalysis.com/PDFS/Advanced%20Rotorbar%20Analysis%20-%20False%20Positives%20-%20Spiders%20-%20Axial%20Cooling%20Vents.pdf
To contact Whitelegg direct please visit http://www.whitelegg.com  

Advanced Rotorbar Analysis – False Negatives: Dual Cage Rotors

 advance rotobar-20022Ernesto J. Wiedenbrug, Ph.D., SM IEEE
Introduction
Some squirrel-cage motors designed for high start-up torque may get weaker over time, needing longer startup times and may perhaps even trip during line-start – but never show big problems in vibration or MCSA. This paper  explains what gives high startup torque motors their  special capabilities, describes a common failure mode  making it nearly impossible to find the issue using MCSA or  vibration, and diagnostic alternatives for these problems.

To continue reading the full case study, with images, please download the free PDF file here. http://csaanalysis.com/PDFS/Advanced%20Rotorbar%20Analysis%20-%20False%20Negatives%20-%20Dual%20Cage%20Rotors.pdf
To contact Whitelegg direct please visit http://www.whitelegg.com  

Device enables fast, easy alignment of rotating plant

scheaffler-204A new handheld laser optical alignment device has been launched that enables faster, easier alignment of shafts in rotating equipment such as fans, motors, pumps, gearboxes, ventilators and compressors.

On show for the first time in the UK at MAINTEC 2013, Schaeffler’s FAG Top-Laser EQUILIGN is a compact, robust, easy-to-use device that guides the user step-by-step through the measurement process until correct shaft alignment is achieved. Graphical operating instructions and an intuitive autoflow function ensure that all maintenance technicians can use the device, regardless of their skills or experience.

The correct alignment of coupled and uncoupled shafts is critical in order to achieve high efficiency and reliability of rotating equipment. Approximately 20% of rotating equipment is incorrectly aligned. A correctly aligned shaft means less friction and vibration are generated by the drive system, which means less wear on belts, pulleys, bearings and seals. This means the running time and reliability of rotating machinery is increased, energy costs are kept to a minimum and overall plant efficiency is improved.

Who monitors the monitoring system?

scheaffler-200Condition monitoring (CM) has been used in the marine industry for many years, typically using data collectors operated by ship's staff. However, with the advent of larger, more complex machinery, particularly on vessels such as large LNG carriers, automated online CM systems have become more popular.

The use of online CM systems has a major advantage in that remote monitoring and advice can be readily provided by fleet technical management, OEMs or shore-based CM specialists. Higher workloads and the reducing number of staff on modern ships also make remote monitoring more attractive. In the event of an alarm condition, an automated monitoring system will typically provide alarm text for the duty engineer in the ECR and an automatic notification to the remote monitoring facility. Trend and analysis data would also be transferred ashore for diagnostic purposes.

Starting new team operations: lessons from greenfield managers

Emerald | Team Performance Management | Table of Contents >> 
Abstract

Purpose – Greenfields are new plants, typically but not exclusively manufacturing, that belong to an existing organization; as such, they offer an organizational strategy for understanding knowledge transfer. Greenfields are important to understand because they offer advantages for expansion into new economic and labor markets. But the overall challenges starting up a new greenfield cannot be overlooked. The aim of this paper is to try to better understand how knowledge transfer occurs in these interesting team operations. Design/methodology/approach – Plant and human resource managers representing 33 greenfield organizations from food and beverage, consumer products, heavy manufacturing, pharmaceutical and automotive industries were contacted. Managers discuss greenfield rationale, vision, work practices, and business characteristics. Both opportunities and risks are described, along with examples from the research literature. Findings – Greenfields can be successful as experiments in knowledge transfer but are unlikely by themselves to create large-scale organizational change. Greenfields offer long-term potential if team work practices and culture can be sustained and ultimately transferred to other parts of the organization, but this requires strong senior management support. Practical implications – Opportunities and risks involved in greenfield start-ups are discussed, along with practical examples from managers from diverse industries. Originality/value – This paper helps to fill the gap between greenfield promise and reality.

Airline downsizing and its impact on team performance

Emerald | Team Performance Management | Table of Contents >> 
Abstract

Purpose – The article draws on a mixed method study of US airline pilots in order to examine the impact of corporate downsizing on pilots' trust, morale, and organizational commitment. The aim of the paper is to review current literature on downsizing and high-risk teams and to identify gaps in the understanding of how external influences like downsizing can impact high-risk team's operational performance through an increase in mistakes, distraction, and stress. Design/methodology/approach – Data were obtained from 127 in depth pilot survey responses from captains and first officers from major US airlines and 43 semi-structured interviews of one to two hours in length. Findings – Commercial pilots working in downsized airlines reported increased stress, distraction, and suspicion with a corresponding reduction in trust, morale, and organizational commitment. Research limitations/implications – The article contributes to the literature in corporate downsizing and high-risk team performance. Insights from these areas provide a lens by which to evaluate post-9/11 managerial decision-making in one high-risk field, aviation, with implications for leadership in other fields of risky work. Originality/value – Although research examining leadership and teamwork in high-risk fields has been growing, few studies consider managerial decisions and the resultant organizational climate within which these teams must operate, particularly in the post-9/11 period. Findings suggest that this is a unique, emerging area that warrants further research.

Do behaviors of string quartet ensembles represent self-managed teams?

Emerald | Team Performance Management | Table of Contents >> 
Abstract

Purpose – This paper aims to explore whether string quartets (SQs) adopt self-managed-team (SMT) principles in line with organizational models of team work. This exploration is significant in face of the status of the SQ as one of the leading and prototypical ensembles in Western music. Design/methodology/approach – Members of 22 leading SQs around the world were contacted and asked to fill out a questionnaire which measures SMT characteristics in managerial teams while referring to their own SQ ensemble. Findings – Results showed that SMT levels of all SQs were extremely high (M=4.39, SD =0.39, on a 1 to 5 scale). In addition, four factors were revealed in this questionnaire: Interpersonal relations and shared monitoring, Leadership, Management style, and Resources explaining 18.4, 15.9, 14.2, and 11.9 percent of the variance, respectively. Research limitations/implications – The current sample is limited in size and may not adequately represent professional SQs worldwide. Nevertheless, this study demonstrates that SQs actually work as SMTs. Additionally, the SMT frame of SQs is expressed in distinct factors of characteristics. Originality/value – The current study is one of a few investigations that examined descriptions of SQ members about behaviors in their own musical ensembles. This study suggests that successful SQs may serve as a benchmark for various SMTs in organizational settings.

Corporate social responsibility, upward influence behavior, team processes and competitive intelligence

Emerald | Team Performance Management | Table of Contents >> 
Abstract

Purpose – The cumulative pool of data piling through the empirical expedition around hospitals in Vietnam provides the clue on whether corporate social responsibility (CSR) influences upward influence behavior, which in turn catalyzes team processes and competitive intelligence scanning. The aim of this paper is to journey through the review of the constructs of CSR, upward influence behavior, and team processes. Design/methodology/approach – Structural equation modeling (SEM) approach served as an analyst for 349 responses returned from self-administered structured questionnaires despatched to 522 hospital members in the middle-management position. Findings – A model of team processes and competitive intelligence evolved along the process of hypothesis testing. Ethical CSR was found to cultivate organizationally beneficial upward influence behavior in the healthcare service organizations. Originality/value – The research findings provide the insight into the CSR-based model of team processes which underscores the role of ethical CSR initiatives and organizationally beneficial upward influence tactics in the activation of competitive intelligence scanning deeds in hospitals in Vietnam business setting.

Cross-functional team effectiveness: An examination of internal team environment, shared leadership, and cohesion influences

Emerald | Team Performance Management | Table of Contents >> 
Abstract

Purpose – Current research remains unclear on what factors contribute to cross-functional team (CFT) success. Thus, the primary purpose of this investigation is to examine internal factors of the team (namely internal team environment, shared leadership, and cohesion) and the influence of each factor on CFT effectiveness. Design/methodology/approach – Structural equation modeling is used to empirically examine the data collected from an undergraduate student sample. Teams worked competitively on a complex task requiring functional area expertise. Findings – Results from the study indicate internal team environment influences effectiveness through shared leadership and cohesion as found in other forms of teams. However, unique to CFTs, internal team environment is not directly related to effectiveness, and shared leadership does not directly influence cohesion. The findings suggest that in CFTs, internal team environment indirectly influences effectiveness. Research limitations/implications – The findings of this study can be used to expand current models of CFT effectiveness. Additionally, by examining the internal dynamics of the team (e.g. internal team environment) researchers will be better able to account for the previous vast differences found in CFT outcomes. Practical implications – Managers interested in influencing team effectiveness are encouraged to focus on the internal dynamics of CFTs. To indirectly influence team effectiveness managers should insure teams establish a clear purpose and that members support one another and feel comfortable making contributions to the team. Originality/value – This investigation offers understanding of how CFTs can be structured to influence effectiveness and provides insight into previously inconsistent findings. Both researchers and managers will benefit from an enhanced understanding of how internal factors uniquely influence CFT effectiveness.

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