Bench Testing of Sensors Utilized for In-Line Monitoring of Lubricants and Hydraulic Fluids Properties

This work reports the results of a study on the behaviour of five sensors recently developed for oil conditions monitoring, installed in-line in an experimental test rig for lubricants. The tests were carried out on seven oils of different origins (one synthetic ester, two bio-based synthetic esters, four vegetable oils) and use (two UTTOs and five hydraulic oils), under controlled working conditions, according to a specially designed test method. At first, the study concerned the identification of the conditions for the correct sensors’ installation. Then, the tests started applying to the fluids severe work cycles intended to accelerate oil ageing. The data of viscosity, permittivity, relative humidity, electric conductivity, particle contamination, and ferro-magnetic particles provided by the sensors were compared to the results of laboratory analyses made on oil samples taken during the tests with the aim of verifying the sensors measurements accuracy and reliability and selecting the more suitable ones to in-line oil conditions monitoring, in the perspective of introducing them also in field applications, e.g., on agricultural tractors, for preventing damages due to oil deterioration, and in managing the machine maintenance.

Synthesis and use of TMP ester biolubricant derived from cottonseed oil in SI engine

Purpose Depleting reserves of crude oils and their adverse environmental effects have shifted focus toward environment friendly and biobased lubricant base oils. Natural oils and fats act as good lubricants but they have low oxidation and thermal stability which makes them unsuitable for modern day uses. This paper aims to produce trimethylolpropane ester biolubricant from cottonseed oil and study the effects of its use in spark ignition (SI) engines. Design/methodology/approach In this work, cottonseed oil is converted to TMP lubricant by a two-step based catalyzed esterification. The lubricants thermophysical properties are then analyzed and a 20% blend with synthetic poly-alpha olefin is used in an spark ignition engine. Findings The produced lubricant has viscosity @100oC of 4.91 cSt, a viscosity index of 230 and a flash point of 202oC. When used as a 20% blend in a petrol engine, the rate of oil deterioration was reduced by 18%, however, the overall wear increased by 6.7%. However, this increase is offset by its improved environmental impacts. Originality/value In its current state, such a biolubricant can be used as an additive to most commercially available lubricants to improve oil deterioration characteristics and environmental impact. However, further work on improving biolubricant’s wear characteristics is needed for the complete replacement of mineral oil-based lubricants.

Lubricating oil deterioration modeling and remaining useful life prediction based on hidden semi-Markov modeling

Lubricating oil, which carries information about machine’s health condition, is of great importance to the performance of machines in the full life cycle. The main purpose of oil deterioration modeling and its remaining useful life prediction is to determine the exact time that the lubricating oil has degraded and it is no longer able to maintain its functions. Generally, lubricating oil deterioration can be partially detected by condition monitoring based on wear debris analysis, and thus can be categorized into three states. In our paper, vector data, which contain wear debris concentration and carry information about the state of lubricating oil, are obtained by an on-line visual ferrograph sensor from a four-ball tester at regular sampling epochs. The oil’s state process is described by a hidden semi-Markov model, and its sojourn times in each state are assumed to be Erlang distributed. A vector autoregressive method based on time series modeling is presented to obtain residual observations, which are regarded as the observable process of oil information in the hidden semi-Markov model framework. The unknown parameters of the hidden semi-Markov model are then estimated by using expectation-maximization algorithm. Afterward, a Bayesian updating approach is presented to derive the explicit formulas of the conditional reliability and mean residual life. To validate the proposed approach, a real case study of lubricating oil deterioration is demonstrated and a comparison with the hidden Markov model is given to illustrate the effectiveness of the new developed remaining useful life prediction approach for lubricating oil.

Engine Oil Deterioration based on the Viscosity, flash point and fire point for Different Trip Length

Fresh engine oils or engine lubricants lose some of their properties during service, engine lubricant deterioration leads to change in oil properties, which ultimately have effect on engine overall performance. Therefore, it is very important to characterize used engine lubricants at different using conditions to check the performance and ability of existing oils, which in turn protects engine parts and also designs new formulations to produce better type of engine oil or improve the existing oil. Therefore, optimizing engine oil lubricant changing time is very important for reducing environmental impact but renewing engine lubricant before it is due rises a customer’s cost. In this study, the most significant parameters such as kinematic viscosity, flash point and fire point were chosen to determine the changes and deterioration in engine oil properties. The oil samples were multigrade fully synthetic with SAE gradation 10W-30 grand ecodrive is used in 5 different passenger cars. Having information about these properties are crucial chemical and physical behaviours of engine oils and for keeping engine’s lifecycle. The test results of this work show that after 10,000 km, 10W-30 Delta NL motor oil brand (special synthetic with API SL) oil properties such as kinematic viscosity at cold start, 40 °C and 100 °C decreased 22.92%, 23.61% and 22.92% respectively. In addition, both flash point and fire point decreased 15.6% and 14.22% consecutively for the base properties, and according to the test results this type of engine oil is suitable to use for 10,000 km.

Experimental evaluation of methanol-gasoline fuel blend on performance, emissions and lubricant oil deterioration in SI engine

Methanol showed promising results as an alternative to gasoline fuel. However, there exists a research gap for the effect of oxygenated fuel on lubricant oil deterioration along-with engine performance and emissions. This study aims the very topic. The characteristics of SI engine were evaluated for two different loads and nine different engine speeds. The lubricant oil samples were taken out from engine oil sump after 100 h of engine operations using gasoline (G) and M12 sequentially. The brake power of M12 was observed higher in comparison with G. The maximum BTE of 23.69% was observed for M12 on lower load and 2800 rpm. On average, the 6.05% and 6.31% decrease in HC emissions were observed using M12 in comparison with G at lower and higher load respectively. M12 produced 32.52% higher NOx emissions than that of G at lower load. The reduction in kinematic viscosities at 40°C of lubricant oil were found 11.61% and 18.78% for M12 and G respectively. TAN, specific gravity, flash point and ash content of lubricant oil were observed 10.23%, 0.079%, 5.81% and 0.97% higher for M12 respectively. The lubricant oil composition could be developed in future for such fuels which may prolong its life cycle.

Analysis of 0W-20 Totachi Brand Oil to Determine the Rate of Oil Deterioration

Engine oil or lubricating oil has a major effect on the engine life and the proper operation of any engine. Changing the engine oil before it is due increases a customer’s cost. The lubricating oil in every engine performs many functions such as reducing friction, preventing corrosion, protecting the engine against wear, removing all impurities, lubricating the moving parts, and cooling the engine parts. There are several causes for the deterioration of lubricating oil, including the properties of the oil, oil quality, and high engine temperatures. Consequently, the deteriorated oil must be replaced at a specified mileage or at specific time intervals to get the best engine performance. It is very important to know when to change the oil, because changing the oil too late can affect the engine parts and vehicle performance. However, replacing the oil too early influences the economy and environment and is an inefficient use of depleting resources. This study describes the kinematic viscosity, flash point, and fire point of multigrade Society of Automotive Engineers (SAE) 0W-20 Totachi (Totachi Industrial Co. Ltd., Japan) international brand oil, which has a 10,000 km guarantee and is approved by and used in 10 different vehicle brands, to determine the rate of deterioration of the parameters. These parameters are the most important physical behaviors of lubricating engine oils. Having information about these parameters is very important for maintaining an engine’s lifespan. The results of this study showed that after 10,000 km, the Totachi oil parameters such as the kinematic viscosity at cold start, at 40°C and at 100°C, the flash point, and the fire point decreased by 22.03%, 25.98%, 26.75%, 16.94% and 17.34%, respectively, from the base values, and that the oil is suitable to use for 10,000 km.

Antioxidant Capacity of Tempura Deep-Fried Products Prepared Using Barley, Buckwheat, and Job’s Tears Flours

Tempura is a dish of battered and deep-fried foods, and wheat flour is typically used; however, barley, buckwheat, and Job’s tears have an antioxidant capacity. This study investigated whether replacing wheat flour with flours from these three crops in tempura affects the antioxidant capacity and deterioration of frying oil. Radical scavenging activity and polyphenol content of tempura were measured by chemiluminescence-based assay and the Folin–Denis method, respectively. The peroxide value, p-anisidin value, acid value, and polar compound of the oil used in frying were measured as indexes of oil deterioration post-frying due to oxidation. Although the frying oil of barley showed higher p-anisidin value than that of wheat, the oil samples’ deterioration level measured in this study was low. The antioxidant capacity and polyphenol content in the three flours samples were higher than those in wheat sample, with buckwheat producing the greatest values, followed by Job’s tears, and then barley. Thus, deep-fried products prepared using the three flours demonstrated superior antioxidant capacity owing to the abundance of antioxidant components. Therefore, tempura can be enjoyed in a healthier manner by using batter prepared using those flours, and substituting wheat flour with the three flours can increase the antioxidant capacity of deep-fried products.