Advancement in Vibration Monitoring Techniques to Identify and Prevent Motor Failures on MOL Pumps at QP Offshore

Case StudyContents: Background Machine description Data analysis: • First Visit • Second Visit Initial Conclusions Machine Inspection results Final Conclusions Actions Taken Lessons Learne

Case Study on Resolving High Vibration Issue of a Centrifugal Compressor at an Offshore Platform

Case StudiesGas Injection Compressors are critical for offshore oil production facilities. A compressor downtime lowers oil production. This case study is about a Gas Injection Compression train at an offshore platform in the Middle East. This case study focuses on how the gradual increase in vibrations was successfully diagnosed, pinpointing the root cause for the high vibration, and finally how it was resolved. The Compression train is equipped with an online vibration monitoring and protection system in addition to a condition monitoring software that was used to diagnose the issue

Resolving Structural Vibration Issues On a Multi Stage Pump

Case StudiesThere are three multistage pumps supplied as part of a new project for transporting diesel from one location to another. Earlier, the transportation of diesel was carried out using trucks for this facility. The availability of these pumps are critical to ensure that the diesel transportation is smooth without the needing the truck services. The machine train is equipped with online vibration monitoring & protection system with online diagnostic software. During the commissioning, it was noticed that the pumps were not able to reach the maximum continuous speed of 50.7 Hz (Max rated speed is 53.8 Hz) and were tripping on high vibration at the pump casing. The operation of these pumps were limited with the speed restrictions using the Variable Frequency Drive (VFD) system. The data review from the online diagnostics system revealed that these pumps were tripping on high vibration due to the excitation of pump vane pass frequency (195 Hz), when the pump was reaching the speed of 39Hz. Further tests concluded that the pump casing natural frequency was matching with the vane pass frequency of 195 Hz. This case study is designed to outline how the high vibration issue was successfully diagnosed, the root cause for the high vibration defined and finally how the problem was mitigated using some of the structural analysis techniques (modal analysis, Operating Deflection Shape etc). Lessons learned are also discussed in view of the discovery methodology using expert system available on site, from the project point of view as well as from design point of view

Resolution of high vibration on a Generator

Case StudyThis is a synchronous generator driven by a GT through a speed reduction gearbox with a rated power of 25 MW(3600 rpm). Generator bearing high vibration levels resulted in several machine trips during the startup attempt followed by a unit shutdown caused by high lube oil temperature. Generator bearings were replaced, exciter misalignment was rectified and insitu balancing of generator rotor was attempted by plant maintenance personnel but did not yield desirable results preventing machine from attaining FSNL speed with acceptable vibration levels.Data indicated dominant 1X amplitudes up to 90 mm/sec Pk at generator inboard bearing confirming generator rotor unbalance coupled with high degree of anisotropic stiffness between horizontal and vertical planes. This case intends to detail how the high vibration issue was successfully diagnosed using various plots from different machine states and resolved by correct insitu balancing approach coupled with bump test technique to identify and eliminate structural resonance

Emerging Markets for GM Foods: A Study of Consumer's Willingness to Pay in India

A random utility approach is used to estimate logit equations which indicate what factors affect the likelihood of consumption of non-GM and GM foods, and, whether or not consumers are willing to pay a premium for non-GM/GM foods. Ceteris paribus as the price difference between non-GM and GM food rose, people were more likely to consume GM foods. Likelihood of GM food consumption was higher in the middle income brackets. Consumers were willing to pay an expected premium of 19.5% and 16.12% for golden rice and GM edible oil respectively. In case of chicken, consumers seemed to pay a very negligible premium for non-GM fed chicken. Overall, it appears that GM foods may be acceptable in the Indian market. However, basic awareness about the GM foods may have to be created among the consumers through government ministries, consumer interest groups, and biotech food-crop companies.GM Foods, Golden Rice, Bt cottonseed oil, GM fed chicken, Willingness to Pay, Random utility approach, Logit, India., Demand and Price Analysis, Food Consumption/Nutrition/Food Safety, Q13, D12,

Emerging Markets for GM Foods: An Indian Perspective on Consumer Understanding and Willingness to Pay

This paper addresses the issues of consumer awareness, opinion, acceptance and willingness to pay for GM foods in the Indian market. A random utility approach is used to estimate a logit equation which indicates what factors affect the likelihood of consumption of non-GM and GM foods and whether or not consumers are willing to pay a premium for non-GM/GM foods. Data was generated through questionnaire survey which was administered to 602 respondents in the city of Ahmedabad and 110 respondents on internet. More than 90% of the respondents from the city survey did not know about GM foods. However, after informing them about the pros and cons of GM foods, more than 70% were willing to consume even if GM and non-GM foods were available for the same price. Ceteris paribus as the price difference between non-GM and GM food rose, people were more likely to consume GM foods. Likelihood of GM food consumption seemed to increase as one moved from very poor and not-so-poor income brackets to higher income brackets. Being a female or a joint family member increased the likelihood of choosing non-GM rice and edible oil. On an average, consumers were willing to pay 19.5% and 16.12% premiums for golden rice and GM edible oil, respectively. Overall, it appears that GM foods will be acceptable in the Indian market. However, consumer education societies, government ministries, and food companies may have to create awareness about the GM foods among Indian consumers.

Development of Mucoadhesive Tablets of Cefuroxime Axetil Loaded in Solid Lipid Nanoparticles.

Nanotechnology can be defined as the science and engineering involved in the design, synthesis, characterization and application of materials and devices whose smallest functional organization in at least one dimension is on the nanometer scale mucoadhesive tablets of cefuroxime axetil loaded in SLNs prove to be a successful gastroretentive oral delivery of the poor bioavailable drug. Since the drug was incorporated into lipids and the particle size was reduced to nano, enhanced permeation was observed and solubility was also increased due to increased surface area. The presence of muco adhesive polymer results in adhesion of tablet to the upper gastric mucosa resulting in targeted drug delivery. The overall results indicate the success of developing mucoadhesive tablets of cefuroxime axetil loaded in SLNs for stomach targeting

Case Study on Remote Diagnostics in Resolving Random Vibration on a Steam Turbine

Case StudyCase Study 7: This case study narrates an incident of random vibration spikes which occurred in year 2014 on one of the steam turbine bearings of a propane refrigeration compressor train. The random vibration spikes caused the turbine high vibration to trip leading to a train shutdown. This case study outlines how the random vibration spikes were successfully diagnosed through remote monitoring center, the root cause for the high vibration trips, and finally how it was mitigated. The case study also discusses lessons learned with respect to the discovery methodology using expert system available at site, and the importance of monitoring key operating parameters

Resolving High Vibration On a Vertical Pump

Case StudyHigh vibration were observed on the motor, pump,structure for more than 2 years with 1X dominant motor vibration. Assuming that the issue is of complete structural issue even though this motor was running well in the past, some structural modifications have been carried out at site which includes a welding a mass of 100 Kg on the structure in addition to the installation of braces to the structure which did not yield any positive results. Structural measurement along with the ODS carried out at site did not reveal a significant issue with the structure itself except for the structural natural frequency slightly closer to the running frequency of the motor. The decision to carry out an onsite balancing on the motor which was intended to remove the excitation force yielded good results which exposed additionally a mistake in the balancing activities carried out by a local vendor at work shop