Journal Of Prognostics And Health Management: Understanding The Conventional Use Of Lubrication In Hot Rolling Machines

Structure of the roller surface and the cause of extreme friction

Discuss About The Journal Of Prognostics And Health Management.

Literature review is one of the most essential part of a research work that holds the importance and the values of the research work. In this literature review the documented data and information have been analysed where the conventional use of lubrication and its potential improvement has been analysed. Apart from that the scientific evidence from various industrial researches have been incorporated that reflects the solid states materials and their chemical properties. The utilisation of this material as lubricant has been also examined with appropriate data and findings. The chemical components and molecular structure of oil, water and Titanium Oxide have been analysed in order to identify their utility as lubricant. The research process also ensured that the selected journals and research papers are not older than 10 years. The purpose of this secondary data collection is to analyse the current dilemma in hot rolling machine usage that have been already identified in various authentic research analysis.

In industrial work rolling machine is used mainly for the making the oil paint mixture, metal and paper sheet. Apart from that in plastic industry the rolling machine is also a widely used equipment that allow the workers to generate huge amount of pressure over both of the flat side of the metal, paper or plastic plate. After analysing the industrial equipment usage throughout the decades it can be said that Rolling Machine is widely used equipment in modern industry where solid state as well as semi solid state metals and non-metals are forcefully reshaped (Poll and Wang 2012). The basic working principle of the rolling machine depends on the double sided forces that are generated by two cylindrical roller. Most of this time this cylindrical rollers are made by special metallic alloy with higher density with high pressure resisting capacity. The electric motor is used to generate enough power to create a angular motion in these two cylinder around their own axis. When the metallic sheet or the solid material are dragged through these two revolving cylinder the amount of pressure produced in that machine creates enormous pressure to make the material flat and thin (Sebald et al. 2014). Therefore, on the exterior surface of the rolling machine receives the maximum pressure both from counterpart and the rolled materials.

Therefore the layer of friction usually works in two separate segments namely upper roll and rolling material, rolling material and lower roll.  As a result both of this friction plane the resultant wear, tear and frictional erosion usually happens in extreme level. Apart from that, in high temperature rolling machine this friction causes 5 to 18% additional heat and unstable temperature that also regulates the operational efficiency and durability of the production material. Similarly, the material quality of rolling machine is also decreased along with its sustainability of exterior surface tension (De Laurentis et al. 2016). Therefore, it causes several cracks and microscopic holes in the rollers. Rolling machines are usually made with non-elastic alloy to increase its survival capacity and durability in continuous and extreme fluctuation of surface temperature. However, this material has specific maximum capacity for having sustainable expansion and contraction. After crossing that specific threshold limit the roller material usually gains extreme tear and wear and even visible cracks on the exterior surface.

Conventional use of lubricant

On the other hand, the lubricant material is used to reduce the molecular scattered structure of the operational surface. The molecules of the lubricant material perfectly distributes throughout the outer surface of the roller and its molecular gaps. Therefore, the effective utilisation of lubricant materials is highly beneficial for the machine as well as for the product components. Throughout the decade many lubricants are usually used to decrease the frictional erosion on the exterior surface of the rolling machine (Askeland 2013). However, all of these lubrication are highly elastic will having lower ability to be distributed over the operational surface. Therefore to increase the efficiency it requires additional maintenance and repeated oiling in the operating rollers and internal gears. This repeated oiling process increases the cauterisation process of this lubricant. The cauterisation causes non-homogeneous distribution of emulsion and frictional misbalance. Therefore, the functionality and the produced material quality are decreased significantly.

In conventional industrial use mainly grease, mixture of oil and water, concentrated fossil fuels and other low friction material are used. When the water based lubricant emulsion is used, the exterior surface of roller loses heat 10 to 12 % more quickly than the other lubricant (Biresaw 2016.).  However, the major problem in the conventional utilisation of lubricant is that generally lubricant produces more heat. Therefore in this current situation the excessive heat generation can be considered as a major problem in conventional lubrication procedure.  Effective lubrication should need the friction reducing properties as well as the heat  releasing properties.  It has been analysed that the overall performance of the Rolling machine is significantly reduced when the conventional process of lubrication is implemented (Lugt 2012). On the other hand, as per the thermodynamic phenomenon of the lubricant material and The Rolling machine, this excess heat is generated by collecting additional power supply from the main power source.  Therefore the resultant power requirement to execute The Rolling process usually increases significantly.  the power required for this additional Energy  requirement is near about 5 to 10% of the actual power  needs (Hashmi 2015).  Similarly the excessive heat and the increased power requirement reduce the operational efficiency of the conventional lubricant.

From the above discussion it is clear that the need of appropriate lubricant in industrial use is significantly noticeable. The Molecules of conventional lubricant have the properties to fill the intermolecular gap in the exterior surface material of the revolving roller.  Apart from that, the conventional lubrication procedure is efficient enough to reduce operational corrosion, wiring and tiring. However the major advantage of this conventional lubricant is these components can improve the productivity of the rolling machine by eliminating the frictional anomaly of the exterior surface of the rolling cylinder (Martin 2014). Large number of alternative lubrications has been used to identify the most effective lubrication procedure for the machines of industrial usage. In spite of all these alternative uses of lubricant emulsion and mixture the effective lubricant has not been identified or developed that has both an anti-frictional property as well as quick temperature releasing quality. Along with that, the optimum requirement for more cost effective lubrication process has to be identified. At the same time the production and maintenance efficiency are also highly dependent on the expense for the lubrication process in any mechanical industry.  The thermodynamical disadvantage causes additional power loss that also increases the operational cost of this rolling machine (Stachowiak, 2015). Ordinary oils assume a vital part in cutting grease and rigging oil. Be that as it may, this sort of added substances is unsuitable in business application because of their impactful smell, poor warm dependability, and extraordinary erosion. This has prompted the need of growing new sort of added substances that can be utilized as a substitute.

Oil based lubricants and its working principles and usage

In the hot rolling machines, a blend oil and water is utilized as the effective lubricant, fire retardant, and the coolant. The measure of oil presented in the rolling area is influenced by its plate-out property which is the spreading of oil on the strips and moves, its emulsion security, and wet capacity properties on metallic surfaces. The nano-particles can be all around scattered in the base oil which shows no huge negative impacts on the counter oxidation property. Sulfur mixture, nitrogen heterocycles and graphene subsidiaries were integrated and utilized as added substances in this lubrication procedure (Wright 2011). The tribological properties and consumption opposition of the bearing steel friction, couple in oil-based lubricants are comparatively high. In view of the consequences of tribological tests and the investigation of friction surfaces, different tribochemical instruments regulate the friction forms, and the arrangement of a limit greasing up film.

Usually, in these lubricant, the graphene oxide (GO) experienced asymmetrical synthetic alteration with myristyltrimethylammonium bromide (TTAB) to get adjusted graphene oxide (MGO) (Ghalme, Mankar and Bhalerao 2013). This MGO was utilized as an emulsifier and added substance in oil-in-water emulsion. The MGO extraordinarily enhanced the soundness of base emulsion and diminished its bead estimate. Tribological test comes about demonstrated that under the limit lubrication condition with MGO emulsion, the friction coefficient (COF) and the wear rate of the steel ball diminished by around 18% and 48% individually in correlation with base emulsion lubrication (Rudnick 2017). The tribological instruments of MGO emulsion use to be clarified by the solid film-framing capacity on the metal surface, the high lubricity of its little beads, and the shaped adsorption film, exchange film and tribofilm between the contact surfaces.

The graphene oxide (GO) was single and twofold sided changed with octadecylamine (ODA) to get MGO1 and MGO2 separately. MGO1 and MGO2 were fused into the O/W base emulsion to change the organization of the interface and the oil stage. It was discovered that the tribological properties of MGO1-containing emulsion were superior to those of MGO2-containing emulsion (Shahnazar, Bagheri and Hamid 2016). Synthetic structure investigation of the well used surfaces proposes that MGO1 nanosheets may adsorb all the more effortlessly onto the metal surface and respond better with metal surfaces to deliver C-N-O-Fe-containing mixes than do MGO2 nanosheets, which implies MGO1 nanosheets are all the more effectively engaged with the shear procedure that happens in the contact region. Nanoindentation showed that there was a non-uniform gentler MGO1 tribofilm exhibit on the metal substrate (Poll and Wang 2012). For O/W emulsion lubrication, if the beads can be immediately adsorbed onto metal surface, shaping a sleek layer between the rubbing surfaces, the COF will be decreased. On the off chance that combined with the arrangement of a compelling adsorption film and tribofilm by added substances, the COF will be additionally decreased. For water-glycol lubrication, the distinctions in the tribological exhibitions are expected essentially to the distinctions of the framed adsorption film and the tribofilm on the rubbing surface, including the shaping speed, quality and thickness and the piece (Ahmadi et al. 2013). These change with the added substances as well as with the working conditions.

With respect to, the likelihood of presenting new ones, which are less unfavorable towards condition, is contemplated in lab scale. This is improved the situation cold rolling , both of an Al-composite and a low carbon steel. The lubrication execution of such recently created – water-based – synthetic lubricants is contrasted and at present utilized mineral oils and emulsions. By utilizing the exploratory technique for "forward slip" estimations joined with piece strategy figurings and FE-reenactments, friction coefficients are assessed for various single pass diminishments (Zolfaghari et al. 2016). Lubricants bearing limit and the item surface unpleasantness are additionally assessed. The outcomes are empowering. the impact of the water stage on lubrication execution of O/W emulsion was looked into. For that, two nitrogen-containing water-dissolvable added substances are incorporated and utilized as an added substance in O/W emulsion. The friction tests comes about demonstrated that the two water-dissolvable added substances may be more quickly adsorbed to the metal surface than the emulsion beads could be "plated out" on the metal surface, along these lines changing the friction-lessening and against wear execution of base emulsion (Mao et al. 2012). Likewise, it was discovered that the tribological properties of these two added substances were connected to nitrogen content as well as to the useful gatherings shaped by the nitrogen molecules.

The impacts of sulfur component and connected load on the tribological execution of water-glycol liquid were considered. For that, two triazine subordinates, STB and STC were integrated and utilized as added substances in water-glycol base liquid (mass proportion 1:1) (Cao et al. 2015). Water dissolvability tests demonstrated that STB and STC met the solvency essential for a water-solvent added substance. The tribological tests utilizing a four-ball tribometer demonstrated that STB and STC both enhanced incredibly the PB esteem, hostile to wear and friction-lessening limits of the base liquid. In view of friction test results and wear scar investigation, it was inferred that the distinctions in tribological exhibitions of STB and STC tests were expected basically to the distinctions of the sulfur content and the sulfur action in added substances. XPS found that STB-tribofilm primarily contained sulfate, however STC tribofilm contained sulfide also (Dai et al. 2016).

A synthetic water-based ointment, utilized as a part of the cool rolling of an Al-amalgam, demonstrated great lubrication capacity, superior to the mineral oil however more terrible than the emulsion. The moved Al-strip complete was observed to be finest for the synthetic ointment took after by the mineral oil and the emulsion. Comparable outcomes were acquired from the steel rolling. Here four synthetic lubricants were contrasted and two mineral oils and one emulsion (Carou, Rubio and Davim 2015). The best ointment was observed to be one of the water-based synthetics, demonstrating the least estimation of the friction coefficient and a smooth item surface. Most emulsions are made out of intrinsically immiscible water (W) and oil (O), and they are grouped into two sorts: the O/W (oil in water composes, in which oil beads are scattered in a constant water stage) and the W/O (water in oil) (Wang et al. 2013). For instance, drain is an O/W write emulsion in which oil fat beads (margarine) are scattered in water with the guide of casein (a kind of protein) emulsifier. It creates the impression that drain and cream (an O/W write emulsion with moderately high oil content) have for some time been utilized as lubricants. Normal dairy animals' drain was once utilized as a cutting answer for the machining of Ti and other hard to-cut materials and as the grease for some uncommon plastic working procedures. Be that as it may, common bovine's drain contains undesired constituents, making optional washing and waste arrangement preparing essential. Hence common drain lubricants have now been supplanted by synthetic emulsion lubricants (Clauss 2012). Indeed, even today, butterfat and other characteristic organic oils are generally utilized as base oils for emulsions, while synthetic surface activators are ordinarily utilized as emulsifier.

The impact of sub-atomic chain length, added substance fixation and sliding speed on the tribological execution of water-glycol liquid was researched. For that, three novel xanthate-containing water-solvent triazine subsidiaries, EXT, BXT and HXT, were combined and utilized as added substances in water-glycol base liquid. It was discovered that the added substance containing tests had no destructive impact on the cast iron and copper surface inside 2.5 wt.% added substance (Ilie and Covaliu 2016). The tribological test comes about utilizing a four-ball tribometer demonstrated that the three added substances incredibly enhanced the PB esteem, friction-decreasing and against wear exhibitions of water-glycol. XPS comes about demonstrated that the added substances had responded with the contact metal surfaces and framed complex tribofilms made out of iron oxide, press sulfide and iron sulfate, which may add to the lessening of friction coefficient and wear rate of the friction framework (Ooi, Sayuti and Sarhan 2015).

Vrious nano-particles are efficient for this cooling process, titanium dioxide been one of them. In opposition to the regular strong state lubricants, additivities with nano-particles ensures that particles will connect in brisk pace into the surface contact zone making a defensive layer particularly when utilizing parts with less harshness, and not just stable suspension creation. Nano-TiO2 has anti-wear, friction-diminishing and cooling properties which can lessen the coefficient of rolling and friction constrain amid the hot rolling procedure (Quinchia et al. 2012). TiO2 has potential application in the steel rolling procedure and machine cutting procedure.

 The coefficient of execution of a refrigeration framework can be enhanced if a lessening in crafted by pressure can be accomplished by an appropriate system, for a predefined warm evacuation rate. The impact of scattering a low centralization of TiO2 nanoparticles in the mineral oil based grease can be differ on its consistency and lubrication qualities, and also varies on the general execution of a Vapor Compression Refrigeration System utilizing R12 (Dichlorodifluoromethane) as the working liquid (Borugadda and Goud 2014). An upgrade in the COP of the refrigeration framework has been watched and the presence of an ideal volume part saw, with low convergences of nanoparticles suspended in the mineral oil. The material science engaged with the association of nanoparticles with the base liquid has been additionally explained by evaluating the Optical Roughness Index utilizing a Speckle Interferometer, by performing estimations on the stick surface after tests with a Pin-on-Disk analyzer. The added substance utilized as a part of the mineral oil based ointment was TiO2 in the nanoparticle shape. The normal size of the nanoparticles had a scope of 30e40 nm and was provided by Sigma Aldrich Limited USA (Mang 2014). Mineral oil e-TiO2 nanofluid tests with various volume divisions of TiO2 nanoparticles were readied utilizing ultrasonic fomentation for accomplishing great scattering of the particles in the base liquid. The required weight of the TiO2 nanoparticles comparing to the volume part was precisely estimated utilizing a high exactness electronic adjust.

To enhance the oil-solvency of nanoparticles, another innovation is utilized to set up a sort of oil containing titanium dioxide (TiO2) nanoparticles. The microstructures of the arranged nanoparticles can be portrayed by means of transmission electron magnifying instrument (TEM) and infrared spectroscopy (IR) (Zhu et al. 2013). Tribological properties of TiO2nanoparticles are utilized as an added substance in base oil by utilizing four-ball tribometer and ball-on-plate tribometer. Also, the well used surface of the steel ball was researched by means of spellbound microscopy (PM) and X-beam photoelectron spectroscopy (XPS). The TiO2 nanoparticles can be totally all around scattered in the base oil under another procedure (NP), which has no fundamentally negative impact on the counter oxidation property. The consequences of the tribological tests demonstrate that TiO2 nanoparticles under the NP demonstrate a superior hostile to wear property and friction-diminishing property in base oil contrasted with TiO2 nanoparticles under the convention procedure (TP) (Pirro, Webster and Daschner 2016). This technique was first used to plan grease containing TiO2 nanoparticles and after that utilized as added substances in motor oil, outfit oil, and other modern lubricants. In the meantime, tribological properties of TiO2 nanoparticles in base oil as a greasing up added substance were additionally contemplated.

Every research needs to follow a particular philosophy that shows the most appropriate way of conducting research and analysing data as well as building the conceptual model from the study. The research philosophy allows finding out the research aspect, approach and mode of data collection dor the research project. In this context, to find out the practical implementation of lubrication process in hot rolling machine the research philosophy should be selected as a guide of realistic operational analysis (Greenfield 2016).  There are three optional research philosophies that are mostly used in any kind of research namely Realism Philosophy, Positivism Philosophy and Interpretivism Philosophy. Each of these philosophies has unique perception and guidelines to conduct a particular research. This research needs both realistic real time data collection with secondary interventions from literature reviews.  Therefore in order to analyse the mechanical as well as frictional activities of conventional lubricants and to find out the most cost effective way of lubrication this research has followed positivism philosophy.  

Research design is the basic foundation of a research project that helps to design the activities and their sequence in order to achieve the aim and objectives of the research. On the other hand the research design also helps to determine the collection process and usable tools for the research. There are three types of research designs that are used to develop the research conduction process and the sequence of activities namely Explanatory Design, Exploratory Design and Descriptive Design. In this context, the research needs to identify the most appropriate lubrication process where there is no previously delivered Hypothesis of concept that is going to be justified to proven (Shahrom, Yahya and Yusoff, 2013). Therefore, in order to identify the most effective lubricant for the hot rolling machine the research requires analysing the working principles of different conventional lubricant with the descriptive research design.  The descriptive research design allows the researcher to explore the context with the help of data collection and analysis that can find out the target answer of this research that are ‘What’ and ‘How’.

The research approach is one of the most important regulatory factors of a research that determines the implementation of the research strategies and the selected tools for the study.  The research approach also implies the mode of research conduction and the process of handling the collected data during the execution of the research method. There are two types of research approach namely Inductive Approach and Deductive Approach to develop the correct approach for a particular research project. In this context, the research needs to identify the most appropriate lubrication process where there is no previously delivered Hypothesis of concept that is going to be justified to proven. Therefore, in order to identify the most effective lubricant for the hot rolling machine the research requires analysing the working principles of different conventional lubricant with inductive research approach (Lim, Baeand Kim 2014). Therefore in order to analyse the mechanical as well as frictional activities of conventional lubricants and to find out the most cost effective way of lubrication this research has followed Inductive research approach.  Research tools:

The research tools are selected to measure the physical properties of the various emulsions as well as the resultant frictional force in the rolling machine. This experiment has been targeted to analyse the regulatory capabilities of various emulsion of Oil, water and Titanium Oxide nano-particles. To conduct this experiment an advance Experimental Rolling Mill has been arranged through which the frictional efficiency of lubricants are being tested. This Experimental Rolling Mill has an inbuilt torque sensor mounted on the both rollers. Apart from that a display system of operational force shows the exact applied force on the rolling metal sheet. Despite that, the optional mounting system of thickness measuring gauge also situated just behind the two rollers.  An Infrared Thermometer is being used to monitor the temperature fluctuation during the rolling process as well as the initial and final temperature of the rolling machine and the metal sheet. Coulter LS 230 Leisure Diffraction tool is used to determine the molecular level distribution of lubricant. The LS230 Leisure Diffraction tool is able to measure the angular diffraction for nano particles of 0.4 to 2000  µm. The Droples size distribution is being measured through this leisure diffraction tool.  EHD Ultra thin sheet Measurement System has been selected as the thickness measurement tools for metal film. This EHD system has been mounted internally within the Rolling machine. The research will be conducted on the Low Carbon Sheet Metal sheet with higher resistance and hardiness than other metals of industrial use.

Data collection is the major activity of the research that defines the research outcomes. However, the data collection procedure is divided into two parts namely primary data collection and secondary data collection. In this research both Primary and Secondary data collection has been used. In Secondary data collection the analysing several critical research journals has been done where the work performance of lubricant in hot rolling machine has been measured (Flick, 2015). The research process also ensured that the selected journals and research papers are not older than 10 years. The purpose of this secondary data collection is to analyse the current dilemma in hot rolling machine usage that have been already identified in various authentic research analysis. The primary data collection has been done with the help of various scientific physical properties measurement tools. In primary data collection the efficiency of lubricant has been identified by using measuring metal shit thickness deference between before and after the rolling process with the help of EHD Ultra Thin sheet measurement system. Apart from that, the droplet size distributions of   Oil emulsion, Water emulsion and Titanium Oxide emulsion has been measured with the help of Leisure Diffraction tool.

Data analysis is the fundamental process within research project that is used to find out the research outcomes by analysing the collected data and information logically. Two types of data analysis processes are used in research project namely Qualitative analysis and quantitative analysis. In this research, the qualitative data analysis has been done on the collected data from secondary data collection. For qualitative analysis various researches conducted on the selected topic have been analysed. In the   quantitative analysis the changes in film thickness, the distribution area of droplet has been measured mathematically. The graphical representation of collected data has been projected as per the quantitative interpretation (Panneerselvam, 2014). In this research the lubrication efficiency has been measured under a constant vertical force while changing the temperature of the lubricant substance from 60degree to 200 degree Celsius. In thickness calculation there will be to variables namely the speed of the rolling machine and the resultant thickness of output material. These two variables have been regulated as per the secondary parameter. The temperature of the lubricant has been considered as the secondary parameter of these variables.

Ethical consideration is highly important for ensuring the credibility and authentication of the research. In the ethical consideration of this study many moral and ethical factors within the execution of the research methods have been kept in mind. The research method has been designed under the regulation of work health and safety act. The method of this research has ensured that the process of this research does not cause any physical harm to the researchers as well as the supportive workforce. The participation of this mechanical experimental procedure is not a forceful factor. All the participants and even fellow researchers are free leave the laboratory premise. All of the equipments and chemicals that are used to conduct this experiment are completely authorised by the local government with valid reasoning.  For safety and security measure the first aid system has been arranged within the laboratory premises to treat the unexpected injury initially.     

Droplet size distribution of water based emulsion:

Due Activity:

As per the initial research design and timeline there were 3 regulatory variable that have to be analysed namely the type of lubricant, the impact on the rolling process and the temperature. However, two of these three variables has been utilised to find out the effectiveness of the lubricants namely water emulsion, oil emulsion and Titanium Oxide Nano-perticles.  The limitation in this conducted research is throughout the research the temperature of the lubricant material was constant that is 60 degree Celsius. However, according to the natural thermodynamical phenomena of these liquids, the physical nature f these lubricants can differ due to change in operational temperature. Therefore investigating and examining the change in frictional nature of these lubricants have to be identified while varying the temperature as secondary parameters or variable. On the other hand the secondary research has not been analysed yet.     

Updated Work plan:

Currently, this research outcomes show all the necessary information about lubricant efficiency in a certain temperature. In further work plan the temperature variable has to be incorporated within the experimental activities. On the other hand, the secondary data collection has to be conduct for developing the data required in qualitative data analysis. As mentioned in the research proposal the SAP or saponification identification does not need to be analysed. However, the next updated work plan the research work will only include the Secondary data collection, Primary data collection in variable temperature, qualitative data analysis and quantitative data analysis. There will be no change in the evaluation process.  

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