Effects of cleaning detergent/water-in-oil emulsions on elastohydrodynamic lubrication

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Lu Chen ◽  
Chenchen Xu ◽  
Mingfei Ma ◽  
Wen Wang ◽  
Liang Guo ◽  
...  
Keyword(s):  
Food Production ◽  
Elastohydrodynamic Lubrication ◽  
Water Concentration ◽  
High Water ◽  
Production Equipment ◽  
Content Type ◽  
Base Oil ◽  
Oil Emulsions ◽  
Static Conditions ◽  
Ball On Disc

Purpose The cleaning of food production equipment using cleaning detergents may contaminate the lubricant of the bearings, thereby reducing the bearing service life. The purpose of this paper is to investigate the cause and mechanism of such damage of bearings lubricated by cleaning detergent/water-in-oil emulsions. Design/methodology/approach The emulsion was prepared by adding a mixture of cleaning detergent and water in one base oil. A self-designed ball-on-disc optical interference test rig was applied to examine the effect of emulsion on lubrication and wear of bearing contacts under pure sliding conditions. Findings The emulsion reduced lubricating film thickness at a relatively low-sliding speed but only when the water concentration (20%) in emulsion was high. Water droplets were trapped around the ball-on-disc contact area under static conditions because of a high capillary force. The emulsion can induce damages on the soft surface in the startup mainly due to the presence of water around the contact. Originality/value The basic lubrication behaviour of water/oil emulsions containing cleaning detergent under pure sliding was experimental studied and the mechanism of bearing damage in food production equipment was investigated. Based on the study, the solution to avoid such damage was proposed.

Biodegradable lubricating greases containing used frying oil as additives

2015 ◽  
Vol 67 (4) ◽  
pp. 315-319 ◽  
Author(s):  
Bronislaw Buczek ◽  
Anna Zajezierska
Keyword(s):  
Fast Food ◽  
Production Equipment ◽  
Frying Oil ◽  
Used Frying Oil ◽  
Content Type ◽  
Base Oil ◽  
Used Oil ◽  
Research Concept ◽  
Fast Food Restaurants ◽  
Railway Engineering

Purpose – The aim of this paper was to investigate the possibility of reusing frying oil, obtained during thermal treatment of food in fast-food restaurants for production of plastic greases. Design/methodology/approach – In accordance with the proposed research concept, the used frying oil was to be the base oil of biodegradable plastic greases thickened with calcium 12-hydroxystearate and lithium 12-hydroxystearate. These studies included the determination of the effect of variable amounts of used oil component in the base oil on the properties of the resultant plastic greases. Findings – It was found that the optimum amount of the component in the base oil is 10-15 per cent. Calcium and lithium greases prepared in such a way possess a quality to that of greases prepared with fresh rapeseed oil. Research limitations/implications – Higher concentrations of used frying oil in the base oil adversely affect the degree of thickening, thixotropic properties and dropping point of the grease, as well as, creating technological problems. Practical implications – The investigations, beside their research goals have also a practical character – recycling waste material in place of its present method of disposal. Originality/value – One of the least expensive material, and most commonly used to produce biodegradable lubricants are vegetable oils. In recent years, besides introducing biodegradable lubricating oils, increasing interest is observed in the use of plastic greases of high biodegradability. Now, it is possible to obtain such greases with additive of used frying oils. Biodegradable greases are used as lubrication of open gear, food production equipment, central lubrication system in cars and railway engineering.

scholarly journals A thermal resistances-based approach for thermal-elastohydrodynamic calculations in point contacts

2017 ◽  
Vol 232 (11) ◽  
pp. 2088-2102 ◽  
Author(s):  
Eduardo de la Guerra Ochoa ◽  
Javier Echávarri Otero ◽  
Enrique Chacón Tanarro ◽  
Benito del Río López
Keyword(s):  
Friction Coefficient ◽  
Film Thickness ◽  
Thermal Effects ◽  
Good Accuracy ◽  
Computational Cost ◽  
Point Contact ◽  
Elastohydrodynamic Lubrication ◽  
Point Contacts ◽  
New Approach ◽  
Ball On Disc

This article presents a thermal resistances-based approach for solving the thermal-elastohydrodynamic lubrication problem in point contact, taking the lubricant rheology into account. The friction coefficient in the contact is estimated, along with the distribution of both film thickness and temperature. A commercial tribometer is used in order to measure the friction coefficient at a ball-on-disc point contact lubricated with a polyalphaolefin base. These data and other experimental results available in the bibliography are compared to those obtained by using the proposed methodology, and thermal effects are analysed. The new approach shows good accuracy for predicting the friction coefficient and requires less computational cost than full thermal-elastohydrodynamic simulations.

Effects of out-of-contact lubricant channeling on friction and film thickness in starved elastohydrodynamic lubrication point contacts

2016 ◽  
Vol 231 (4) ◽  
pp. 432-440 ◽  
Author(s):  
Fadi Ali ◽  
Ivan Křupka ◽  
Martin Hartl
Keyword(s):  
Film Thickness ◽  
Digital Camera ◽  
Elastohydrodynamic Lubrication ◽  
Contact Condition ◽  
Friction Reduction ◽  
Rolling Element Bearings ◽  
Point Contacts ◽  
Practical Applications ◽  
Rolling Element ◽  
Ball On Disc

This study presents experimental results on the effect of out-of-contact lubricant channeling on the tribological performance of nonconformal contacts under starved lubrication. Channeling of lubricant was carried out by adding a slider with a limited slot for scraping the displaced lubricant on one of mating surfaces (ball). Thus, the scraped lubricant is forced to flow back into the depleted track through the limited slot resulting in robust replenishment. The measurements have been conducted using optical tribometer (ball-on-disc) equipped with a digital camera and torque sensor. The effect of lubricant channeling was compared to the original contact condition by means of measuring friction and film thickness. The results show that the out-of-contact lubricant channeling leads to a significant enhancement of film thickness and friction reduction under starved conditions. Indeed, the starved elastohydrodynamic lubrication contacts transformed to the fully flooded regime after introducing the flow reconditioning. Moreover, the film thickness decay over time, which is common with starved elastohydrodynamic lubrication contacts, has not been observed in the case of lubricant channeling. However, the beneficial effect of lubricant channeling diminishes as the original contact condition tends to the fully flooded regime. The results of this study can be easily implemented in practical applications such as radial and thrust rolling-element bearings.

Effect of tribological parameters on sliding wear and friction coefficient which relates to preload loss in tapered roller bearing

2019 ◽  
Vol 71 (1) ◽  
pp. 61-73 ◽  
Author(s):  
Ayush Jain ◽  
Abhishek Singh ◽  
Arendra Pal Singh
Keyword(s):  
Sliding Wear ◽  
Roller Bearing ◽  
Wear Test ◽  
Thickness Effect ◽  
Surface Parameters ◽  
Content Type ◽  
Tapered Roller Bearing ◽  
Tapered Roller ◽  
Tribological Parameters ◽  
Ball On Disc

Purpose This paper aims to study the sliding wear and coefficient of friction (COF) using “ball on disc” tribometer. Discs of bearing steel were subjected to different tribological parameters such as heat treatment (through hardening and case hardening), sliding speed, sliding distance and micro-geometry of the functional ball and disc point contact. Results obtained from tribometer were correlated with the preload loss in tapered roller bearing. Preload loss is subjected to wear rate pattern with respect to the internal geometry and micro-geometry of functional surfaces of the tapered roller bearing, caused by internal resistance between roller large ends sliding against cone supporting face. This confirms the optimum geometry and physical/mechanical property of the tapered roller bearing, which makes the use of these bearings under the demanding application in the automotive industry such as differential gears and installation of pinions of differential gears in power transmissions or wheels. Design/methodology/approach The paper opted for an exploratory study using the design of experiments with full factorial method. The approach was to do ball on disc sliding wear test and correlate that sliding wear with preload loss in tapered roller bearing. Findings The paper provides the limit of preload loss in tapered roller bearing. Research limitations/implications Because of the chosen research approach, the research lacks the effect of environmental conditions such as temperature and relative humidity and lube film thickness effect on wear test. It also lacks the validation part with actual preload loss on tapered roller bearings. Above work is included in future scope of work. Practical implications This paper includes the recommendation for surface parameters which can increase the bearing life by reducing the preload loss in tapered roller bearing. Social implications This paper includes the recommendation for surface parameters for bearing manufacturing industries. Originality/value This paper provides the relation between sliding wear and preload loss in tapered roller bearing.

scholarly journals Potential uses of biomass from fast-growing crop miscanthus×giganteus

2012 ◽  
Vol 66 (2) ◽  
pp. 223-233 ◽  
Author(s):  
Nada Babovic ◽  
Gordana Drazic ◽  
Ana Djordjevic
Keyword(s):  
Panicum Virgatum ◽  
Large Scale ◽  
Low Cost ◽  
Water Concentration ◽  
High Water ◽  
Perennial Grasses ◽  
Great Promise ◽  
Cellulose Content ◽  
Production Chain ◽  
Miscanthus Giganteus

There is an increasing interest in perennial grasses as a renewable source of bioenergy and feedstock for second-generation cellulosic biofuels. Switchgrass (Panicum virgatum) and miscanthus (Miscanthus?giganteus), belonging to the parennial grasses group, are the major lignocellulosic materials being studied today as sources for direct energy production, biofuels, bioremediation and other. They have the ability to grow at low cost on marginal land where they will not compete with the traditional food crops. Miscanthus?giganteus possesses a number of advantages in comparison with the other potential energy crops such as are: high yields, low moisture content at harvest, high water and nitrogen use efficiencies, low need for annual agronomic inputs such as fertilizers and pesticides, high cellulose content, non-invasive character, low susceptibility to pests and diseases and broad adaptation to temperate growing environments. The main problems are low rate of survival during the first winter after the creation of plantation and the relatively high establishment costs. Miscanthus?giganteus is grown primarily for heat and electricity generation but can also be used to produce transport fuels. Miscanthus biomass has a very good combustion quality due to its low water concentration as well as its low Cl, K, N, S and ash concentrations compared to other lignocellulose plants. It is expected that miscanthus will provide cheaper and more sustainable source of cellulose for production of bioethanol than annual crops such as corn. Miscanthus has great promise as a renewable energy source, but it can only be realised when the grass production has been optimised for large-scale commercial cultivation. However, further research is still needed to optimise agronomy of miscanthus, to develop the production chain and pre-treatment as well as to optimise energy conversation route to produce heat, electricity, and/or fuels from biomass, if miscanthus is to compete with fossil fuel use and be widely produced.

Effect of tooth waist order parameters of double involute gears on lubrication performance of gear drive

2016 ◽  
Vol 68 (6) ◽  
pp. 671-675 ◽  
Author(s):  
Zhimin Fan ◽  
Wanfeng Zhou ◽  
Ruixue Wang ◽  
Na Wang
Keyword(s):  
Elastohydrodynamic Lubrication ◽  
Reference Value ◽  
Tooth Profile ◽  
Order Parameters ◽  
Content Type ◽  
Oil Film ◽  
Gear Drive ◽  
Involute Gear ◽  
Lubrication Performance ◽  
Involute Gears

Purpose The purpose of this paper is to derive a new lubrication model of double involute gears drive and study the effect of the tooth waist order parameters of double involute gears on lubrication performance. Design/methodology/approach The new lubrication model of double involute gears drive was established according to the meshing characteristics of double involute gears drive and the finite length line contact elastohydrodynamic lubrication theory. Numerical calculation of the lubrication model of gear drive was conducted using the multigrid method. Findings The results show that the oil film necking phenomenon and the oil film pressure peak emerged at the tooth waist order area and the tooth profile ends, and when compared with involute gear, the lubrication performance at the tooth waist order area is better than that at the tooth profile ends. The effect of tooth waist order parameters on lubrication performance at the tooth waist order area was greater than that at other areas. Originality/value This research will promote the application of the double involute gear as soon as possible, and it has the reference value for other types of gears.

Use of Opuntia ficus extract as a corrosion inhibitor for carbon steel in acidic media

2014 ◽  
Vol 61 (4) ◽  
pp. 224-231 ◽  
Author(s):  
Ruben Suarez-Hernandez ◽  
Jose G. Gonzalez-Rodriguez ◽  
Gloria F. Dominguez-Patiño ◽  
Alberto Martinez-Villafañe
Keyword(s):  
Carbon Steel ◽  
Chemical Structure ◽  
Electrochemical Impedance ◽  
Green Inhibitor ◽  
Opuntia Ficus Indica ◽  
Content Type ◽  
Acid Cleaning ◽  
Static Conditions ◽  
The Cost ◽  
Practical Implications

Purpose – The purpose of this investigation is to study the corrosion inhibition of carbon steel (CS) using a “green” inhibitor, Opuntia ficus-indica, in an aerated, 0.5 M H2SO4 solution at different concentrations and temperatures. Design/methodology/approach – Weight loss determinations, surface studies, electrochemical impedance spectroscopy and potentiodynamic polarization were applied during the investigation. Findings – It was observed that Opuntia ficus-indica extract can decrease the corrosion rate of CS, and its efficiency increases with increasing concentration up to 1,000 ppm and with time, but decreases with increasing the temperature from 25 to 600C. The inhibitory activity is due to the presence of phenolic compounds in its chemical structure. Research limitations/implications – The work was done under static conditions, whereas in acid cleaning conditions, there is a dynamic system. However, the findings may apply to both the systems. Practical implications – CS is used in acidic environments in the acid cleaning industry. Social implications – Results of this work show that it is possible to reduce the cost of repair of equipment and the environmental impact of corrosion. Originality/value – There are very few investigations on the study of Opuntia ficus-indica leaf extract as a green inhibitor in an acidic environment.

Impacts of price, weather and policy changes on maize and rice farming in Togo

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Manzamasso Hodjo ◽  
Acharya Ram ◽  
Don Blayney ◽  
Tebila Nakelse
Keyword(s):  
Food Production ◽  
Poverty Reduction ◽  
Positive Impact ◽  
National Level ◽  
Yield Response ◽  
Policy Changes ◽  
Sustainable Food ◽  
Content Type ◽  
Food And Agriculture ◽  
Cropland Allocation

PurposeThis paper aims to investigate how climatic, market and policy factors interact to determine food production in Togo. Specifically, we estimate acreage and yield response to market prices, weather and policy changes for maize and rice.Design/methodology/approachWe use panel data estimators in a Seemingly Unrelated Regressions Equation (SURE) model with region-level data from the Food and Agriculture Organization statistics department and the National Oceanic and Atmospheric Administration (NOAA) of the US Department of commerce.FindingsWe found lower fertilizer price and higher grain price effects on maize acreage and yield. In addition, we found a positive effect of expected rice price on both its acreage and yield. As expected, rainfall during planting months has a significant impact on both maize (April) and paddy (May) acreage allocations. Similarly, total rainfall during the growing season has a positive impact on both maize and paddy yields. Moreover, recent agricultural policy initiative designed to boost domestic food production has significantly increased acreage and yield for maize, and yield for paddy, especially the strategy for agricultural growth.Research limitations/implicationsThe dataset includes region-level observations from 1991 to 2012 which limits the observation span. However, we had enough variability in key variables to determine the estimated coefficients.Practical implicationsAlthough the dataset is limited in time (1991–2012) and uses national-level output prices, this investigation reveals that cropland allocation to maize and rice is sensitive to fertilizer and grain prices, weather expectations and policy interventions. These findings provide evidence for sustainable food production and productivity enhancement in Togo.Social implicationsUnderstanding drivers of cropland allocation and cereal yield contribute to better food security and poverty reduction in developing countries, especially Togo.Originality/valuePrior to this study, little was known on the effect of price, climate and policy on cropland allocation in Togo. This investigation contributes significantly to filling this knowledge gap and provides insights for effective interventions.

Size effect on thermal elastohydrodynamic lubrication of industrial chain bush-pin hinge pair

2019 ◽  
Vol 71 (9) ◽  
pp. 1080-1085 ◽  
Author(s):  
Mingyu Zhang ◽  
Jing Wang ◽  
Yi Liu ◽  
Longjie Dai ◽  
Zhaohua Shang
Keyword(s):  
Friction Coefficient ◽  
Film Thickness ◽  
Temperature Rise ◽  
Elastohydrodynamic Lubrication ◽  
Curvature Radius ◽  
Line Contact ◽  
Content Type ◽  
Oil Film ◽  
Industrial Chain ◽  
Infinite Line

Purpose The purpose of this paper is to use elastohydrodynamic lubrication (EHL) theory to study the variation of the equivalent curvature radius “R” on the change of oil film thickness, pressure, temperature rise and friction coefficient in the contact zone between bush-pin in industrial chain drive. Design/methodology/approach In this paper, the contact between bush and pin is simplified as infinitely long line contact. The lubrication state is studied by numerical simulation using steady-state line contact thermal EHL. The two constitutive equations, namely, Newton fluid and Ree–Eyring fluid are used in the calculations. Findings It is found that with the increase of equivalent curvature radius, the thickness of oil film decreases and the temperature rise increases. Under the same condition, the friction coefficient of Newton fluid is higher than that of Ree–Eyring fluid. When the load increases, the oil film thickness decreases, the temperature rise increases and the friction coefficient decreases; and the film thickness increases with the increase of the entraining speed under the condition “R < 1,000 mm”. Research limitations/implications The infinite line contact assumption is only an approximation. For example, the distances between the two inner plates are 5.72 mm, by considering the two parts assembled into the inner plates, the total length of the bush is less than 6 mm. The diameter of the pin and the bore diameter of the bush are 3.28 and 3.33 mm. However, the infinite line contact is also helpful in understanding the general variation of oil film characteristics and provides a reference for the future study of finite line contact of chain problems. Originality/value The change of the equivalent radius R on the variation of the oil film in the contact of the bush and the pin in industrial chain drive was investigated. The size effect influences the lubrication characteristic greatly in the bush-pin pair.

Demarcation boundary between region dominated by elastohydrodynamic lubrication and that by the surface force action for different elliptical ratios

2017 ◽  
Vol 69 (2) ◽  
pp. 215-224
Author(s):  
Mohamed Abd Al-Samieh
Keyword(s):  
Van Der Waals ◽  
Elastohydrodynamic Lubrication ◽  
Hydrodynamic Pressure ◽  
Surface Force ◽  
Van Der Waals Force ◽  
Line Contact ◽  
Force Action ◽  
Content Type ◽  
Combined Action ◽  
Ellipticity Ratio

Purpose This paper aims to investigate the effect of changing speed of the entraining motion on the formation of ultra-thin lubricating films under different elliptical ratios. The ellipticity parameter (K) varied from 1 (a ball-on-plate configuration) to 6 (a configuration approaching line contact). The influence of the ellipticity parameters, the dimensionless speed and the effects of surface forces on the formation of the minimum film thickness has been demonstrated. The demarcation boundary between region dominated by elastohydrodynamic lubrication (EHL) and that by the surface force action has been demonstrated for different elliptical ratios. Design/methodology/approach The numerical solution has been carried out, using the Newton–Raphson iteration technique, applied for the convergence of the hydrodynamic pressure. The film thickness and pressure distribution are obtained by simultaneous solution of the Reynolds’ equation, the elastic deformation (caused by hydrodynamic pressure, surface force of solvation and Van der Waals force) and the load balance equation. The operating conditions, load and speed of entraining motion, promote formation of ultra-thin films that are formed under the combined action of EHL, surface contact force of solvation and molecular interactions due to presence of Van der Waals force. Findings The paper provides insights about the transition between region dominated by EHL and that by the surface force action for changing ellipticity ratio (K) from 1 (a ball-on-plate configuration) to 6 (a configuration approaching line contact). Originality/value This paper fulfils an identified need to study the effect of changing ellipticity ratio on the formation of ultra-thin films that are formed under the combined action of EHL, surface contact force of solvation and molecular interactions due to presence of Van der Waals force.

Sign in / Sign up

Export Citation Format

Share Document