P.S. Mukherjee

Advancement and current status of wear debris analysis for machine condition monitoring: a review

Purpose – The dependency on human expertise for analysis and interpretation is the main reason for wear debris analysis not being used in industry to its full potential and becoming one of the most powerful machine condition monitoring strategies. The dependency on human expertise makes the interpretation and result subjective in nature, costly and time consuming. The purpose of this paper is to review work being done to develop an automatic, reliable and objective wear particle classification system as a solution to the above problem. At the same time it also aims to discuss some common off line test methods being practiced for wear debris analysis.Design/methodology/approach – Computer image analysis is a solution for some of the problems associated with the conventional techniques. First it is tried to efficiently describe the characteristics of computer images of different types of wear debris using a few numerical parameters. Then using some Artificial Intelligence tools, the wear particle classifica...

Online condition monitoring of engine oil

Purpose – Engine oil degrades in quality during its use and after certain period of time the oil needs to be changed depending upon its condition. The purpose of this paper is to design and develop an online condition monitoring device for engine oil.Design/methodology/approach – Based on the previous works in this line and some testing of used oils in the laboratory, the correlation of change in colour with other properties were identified. An optical colour sensor was then designed and developed which can transform the darkness of oil colour into electrical resistance. A series of tests were undertaken to calibrate the system for its correctness.Findings – This type of sensor provides the information about the condition of the oil and also can inform about the probable time for drain‐off of the oil.Practical implications – Engine oil changes are normally done by schedules which are highly conservative and cost the user as the oil is changed when it could be still used for some time. Use of an online sen...

Additives depletion and engine oil condition: a case study

Purpose – To study and estimate changes of various properties upon use of engine oil by different methods.Design/methodology/approach – By viscosity measurement, pH measurement, Fourier transform infra‐red spectroscopic analysis and UV‐Visible (Ultraviolet and visible rays) spectroscopic analysis.Findings – Some specific changes in additives of the oil upon use could be traced.Practical implications – Correct choice for additives for a particular use may enhance the oil life and also protect the engine from damage.Originality/value – The findings may be important to the lube oil producers and the users.

Assessment of useful life of lubricants using artificial neural network

Most catastrophic failures of machines result from improper lubrication. The cost of lubricants can be up to 10‐12 percent of the production cost an essential part of maintenance management, therefore it is essential that the optimization of lubricants is at the optimum. This paper decribes and considers present practice in lubricant condition monitoring.

Interrelationship among viscosity, temperature and age of lubricant

Purpose – To provide a general equation for finding out viscosity of lubricating oils at different temperatures and ages.Design/methodology/approach – Based on previous works and a case study on field, a general equation was formulated which relates viscosity‐temperature‐age of lubricant.Findings – The equation is very simple and a good consistency was found.Practical implications – This equation will help the designers/manufacturers to recommend the correct grade of lubricating oil.Originality/value – This type of relationship was never reported earlier.

RULL assessment by FTIR – a case study on HEMM in Indian mines

Scheduled rejection of lubricants in central lubrication systems often leads to loss of lubricants as these could be used for a further long period. To avoid such loss, periodic monitoring of lubricants is suggested so as to forecast the time when the lubricant in a particular system of equipment loses its properties and requires to be drained‐off and charged afresh. To assess the remaining useful life of lubricant (RULL) in use, a new method by fourier transform infrared (FTIR) spectroscopy is used. The work is supplemented by a case study on heavy earth moving machinery (HEMM) deployed in Indian mines.

Development of bearings for a small high speed cryogenic turboexpander

Purpose – The purpose of this paper is to examine the development of aerodynamic thrust bearings and aerodynamic journal bearings applied to a small high speed cryogenic turboexpander in Indian conditions.Design/methodology/approach – As a part of indigenous programme in the process of development, some input parameter was taken from the available literature and then dimensions were optimized and computed while taking care to minimize fabrication constraints.Findings – A series of tests were conducted to confirm the findings. Detailed study of the effect of stability and vibration of bearings was taken up. The maximum rotational speed obtained was 200,000 rpm.Practical implications – The outcome may help the designers, researchers and manufacturers of these components.Originality/value – Although manufacturers design and develop the bearings of turboexpanders for their production, no academic literature has been available for this purpose until now.

Analysis of wear generation in mine excavator bucket

Purpose – The purpose of this paper is to explore the wear phenomena on the bottom surface of an excavator bucket and optimize the design parameters to reduce wear rate by converting sliding motion to rolling motion of rock during the time of operation. Design/methodology/approach – A test rig has been developed to study the wear phenomena and type of wear on the excavator bucket. Three different bottom plates have been fabricated for experiments to observe the difference of severity of wear in terms of volume of material removal. Findings – It has been observed that the bottom plate having the mesh-type wear bar pattern was comparatively more resistive to wear than the other two models. Wear-affected zone on the bottom plate was also detected and represented with the help of colour contour. Practical implications – It is expected that these findings will contribute towards the development of the bottom plate of the excavator bucket with some new pattern of a wear bar, which will be efficient to reduce th...

Analysis of nanofluids as a means of thermal conductivity enhancement in heavy machineries

Purpose – Nanofluids exhibit enhanced heat transfer characteristics and are expected to be the future heat transfer fluids particularly the lubricants and transmission fluids used in heavy machinery. For studying the heat transfer behaviour of the nanofluids, precise values of their thermal conductivity are required. For predicting the correct value of thermal conductivity of a nanofluid, mathematical models are necessary. In this paper, the effective thermal conductivity of various nanofluids has been reported by using both experimental and mathematical modelling. The paper aims to discuss these issues. Design/methodology/approach – Hamilton and Crosser equation was used for predicting the thermal conductivities of nanofluids, and the obtained values were compared with the experimental findings. Nanofluid studied in this paper are Al2O3 in base fluid water, Al2O3 in base fluid ethylene glycol, CuO in base fluid water, CuO in base fluid ethylene glycol, TiO2 in base fluid ethylene glycol. In addition, stu...

Analysis of lubricant use in mining equipment – a tool for maintenance management

Looks at the use of lubrication in the maintenance of mining equipment through the examination of five case studies of mines from different areas and their consumption of lube oil. Concludes that a suitable management of lubricant consumption plays an important role in production costs and optimization.