scholarly journals Preparation and Tribological Properties of Lanthanum Stearate Modified Lubricating Oil for Wire Rope in a Mine Hoist

Materials ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 5821
Author(s):  
Yewei Zhang ◽  
Qing Zhang ◽  
Yuxing Peng ◽  
Chen Wang ◽  
Xiangdong Chang ◽  
...  

In view of the serious friction and wear on the surface of a hoisting wire rope caused by the failure of lubrication under severe hoisting conditions, a study on the tribological characteristics of lanthanum stearate modified lubricating oil (LSMLO) was carried out. First, lanthanum stearate was prepared by the saponification reaction, and its surface morphology, chemical structure, thermal stability, and dispersion stability in IRIS-550A lubricating oil (IRIS) for wire rope were analyzed. Then, the tribological properties of LSMLO were investigated through four-ball friction tests and sliding wear tests of wire ropes. The results show that stearic acid almost completely reacts to produce lanthanum stearate, which has good thermal stability and a disordered layered structure. With the help of oleic acid, the dispersion stability of lanthanum stearate in IRIS can be significantly improved. The four-ball friction tests show that the optimal addition amount of lanthanum stearate in IRIS is 0.2 wt.%, and the CoF and wear scar diameter are reduced by about 35% and 25% respectively when lubricated with LSMLO compared to that with IRIS. LSMLO can better reduce the wear of the wire rope under different sliding speeds and contact loads than IRIS, and it exhibits improved anti-friction and anti-wear properties under high speed and low load.

MRS Advances ◽  
2018 ◽  
Vol 3 (64) ◽  
pp. 3979-3985
Author(s):  
Brenda Castaños ◽  
Cecilia Fernández ◽  
Laura Peña-Parás ◽  
Demófilo Maldonado-Cortés ◽  
Juan Rodríguez-Salinas

ABSTRACTGreases are essential in the electrical industry for the purpose of minimizing wear and coefficient of friction (COF) between the components of circuit breakers. Nowadays some researchers have explored the addition of nanoparticles to enhance their tribological properties. In this study, tribological tests were performed on different greases employed for the electrical industry. CuO and ZnO nanoparticles were homogeneously dispersed into the greases, varying their concentration (0.01 wt.%, 0.05 wt.%, and 0.10 wt.%). A four-ball tribotest, according to ASTM D-2266, and a ball-on-disk tribotest, according to ASTM G-99, were performed in order to analyze the wear scar diameter (WSD), COF, wear mass loss and worn area. The worn materials were characterized with an optical 3D profilometer measurement system. Anti-wear properties were enhanced up to 29.30% for the lithium complex grease (LG) with no nanoparticles added, in comparison with the aluminum complex grease (AG), providing a much better tribological performance; in the ball-on-disk tribotests, a 72.80% and a 15.74% reduction in the mass loss and COF were achieved, respectively. The addition of nanoparticles was found to provide improvements of 5.31% in WSD for the AG grease and 34.49% in COF for the LG grease. A pilot test was performed following the security test UL489, achieving a reduction of 45.17% in the worn area achieved by LG grease compared to AG grease.


Lubricants ◽  
2019 ◽  
Vol 7 (2) ◽  
pp. 11 ◽  
Author(s):  
Jankhan Patel ◽  
Amirkianoosh Kiani

In this study, reduced graphene oxide (rGO) nano platelets were used as an additive to enhance friction and wear properties of oil-based lubricants by preparing three samples at 0.01% w/w, 0.05% w/w, and 0.1% w/w concentrations. To analyze the direct effect of rGO nano platelets on tribological properties, 99.9% pure oil was used as a liquid lubricant. A comparative tribological study was done by performing a ball-on-disk wear test in situ under harsh conditions, which was further analyzed using a non-contact 3D optical profilometer. Morphological evaluation of the scar was done using transmission and scanning electron microscopy (TEM, SEM) at micro and nano levels. The lubricants’ physical properties, such as viscosity and oxidation number, were evaluated and compared for all samples including pure oil (control sample) as per ASTM standards. Findings of all these tests show that adding rGO nano platelets at 0.05% w/w showed significant reduction in friction at high speed and in wear up to 51.85%, which is very promising for increasing the life span of moving surfaces in machinery. Oxidation and viscosity tests also proved that adding rGO nano platelets to all samples does not sacrifice the physical properties of the lubricant, while it improves friction and wear properties.


2019 ◽  
Vol 247 ◽  
pp. 60-62 ◽  
Author(s):  
Tao Li ◽  
Liangcai Wu ◽  
Yong Wang ◽  
Guangyu Liu ◽  
Tianqi Guo ◽  
...  

2020 ◽  
Vol 10 (4) ◽  
pp. 1305
Author(s):  
Yongbo Guo ◽  
Dekun Zhang ◽  
Xinyue Zhang ◽  
Dagang Wang ◽  
Songquan Wang

A new transmission theory of “global dynamic wrap angle” for friction hoist is proposed. The theory is based on a mine hoist simulation model which combines the suspended rope with the wrapped rope. Rope dynamics in a suspended section are verified by the field experiment results. The theory holds that the mechanical state of wire rope is dynamic through the whole wrap angle, including deformation, contact and friction. When the rope enters the wrap angle, it provides positive friction and changes direction at a certain boundary point. The demarcation of the boundary depends on the rope load on both sides of the friction pulley. The theory is suitable for accurately analyzing the kinetics of high-speed and heavy-load friction hoisting.


2016 ◽  
Vol 68 (5) ◽  
pp. 611-616 ◽  
Author(s):  
Zujian Shen ◽  
Fei Geng ◽  
Xinxin Fan ◽  
Zhichen Shen ◽  
Haiyan Wang

Purpose This paper aims to investigate and prepare the composite polyurea greases with excellent thermal stability and tribological properties. Design/methodology/approach In this paper, composite Ba-based (Ba, barium) tetra-polyurea lubricating greases were prepared with two different methods: mixing Ba-based gelatinizer and tetra-polyurea gelatinizer by a physical method; and introducing barium carboxylate into tetra-polyurea molecules by a chemical method. The properties of the products, such as heat stability, water resistance and friction performance, were analyzed with thermogravimetry, water-resistance test and four-ball friction test. Findings The results indicated that the products obtained by chemically introducing barium carboxylate into tetra-urea molecules showed better elevated temperature tribological properties, and the disadvantages of the polyurea greases with high temperature hardening were also obviously improved. The cone penetration rate at 180°C for 24 h is only 3 per cent. The friction coefficient can be decreased to 0.44 and the last non-seizure load value was increased from 560 N to 1,120 N without any other additives. Originality/value The research is significant because the prepared composite grease showed excellent performances, such as the outstanding thermal stability, water resistance and excellent extreme pressure and anti-wear properties, which may be widely applied in steel, metallurgy, bearings and other industrial fields.


2011 ◽  
Vol 197-198 ◽  
pp. 540-543 ◽  
Author(s):  
Zhi De Hu ◽  
Hua Yan ◽  
Xue Mei Wang ◽  
Hai Zhe Qiu

Magnetorheological fluid (MRF) is a new kind of smart material, it is very necessary for us to study its tribological properties because it will be widely used in engineering application. In this paper, the tribological behavior of Carbonyl Iron-based magnetorheological fluid (MRF) was investigated on a four-ball tribological tester, the influence of lubricant on friction coefficient and wear scar diameter was discussed, the morphology of the wear steel surfaces lubricated with MRF were observed by a scanning electron microscope. The results show that the addition of MoS2can significantly improve the tribological properties of clay-based MRF. However, the friction and wear properties of silica-based MRF become bad after the addition of MoS2. The morphology of worn surface lubricated with the MRF added MoS2is similar to that without additive, but the groove of wear marks lubricated with clay-based MRF is more shallower and the area of the worn surface is smaller in the condition of adding MoS2.


2013 ◽  
Vol 781-784 ◽  
pp. 988-992
Author(s):  
De Zhong Liao ◽  
Jie Yu He ◽  
Li Xin Mao ◽  
Yi Xue Xu

Several complex esters were synthesized from phthalic anhydride, neopentyl glycol and rapeseed acid. Their rheological properties, biodegradability and tribological properties were measured. It was found that the complex esters have a wide viscosity range of 126~325mm2/s at 40°C with viscosity indices about 127~143, and solidifying points lower than-38°C. The maximum non seizure load of a complex ester with degree of polymerization 1.42 is as high as 735 N, with a wear scar diameter of 0.41mm, superior to mineral oil. The biodegradation rates are higher than 73%, and the thermal stability is good. So these complex esters are a class of green synthetic ester oils with excellent properties.


2015 ◽  
Vol 67 (3) ◽  
pp. 227-232 ◽  
Author(s):  
Yujuan Zhang ◽  
Yaohua Xu ◽  
Yuangbin Yang ◽  
Shengmao Zhang ◽  
Pingyu Zhang ◽  
...  

Purpose – The purpose of this paper is to synthesize oil-soluble copper (Cu) nanoparticles modified with free phosphorus and sulfur modifier and investigate its tribological properties as environment-friendly lubricating oil additives. Design/methodology/approach – To improve the anti-oxidation properties of these nanoparticles, two kinds of surface modifiers, oleic acid and oleylamine were used simultaneously. The morphology, composition, structure and thermal properties of as-synthesized Cu nanoparticles were investigated by means of transmission electron microscopy, X-ray powder diffraction, Fourier transform infrared spectrometry and differential thermal and thermogravimetric analysis. The tribological properties of as-synthesized Cu nanoparticles as an additive in liquid paraffin were evaluated with a four-ball friction and wear tester. Findings – It has been found that an as-synthesized Cu nanoparticle has a size of 2-5 nm and can be well dispersed in organic solvents. Tribological properties evaluation results show that as-synthesized Cu nanoparticles possess excellent anti-wear properties as an additive in liquid paraffin. The reason lies in that as-synthesized surface-capped Cu nanoparticles are able to deposit on sliding steel surface and form a low-shearing-strength protective layer thereon, showing promising application as an environmentally acceptable lubricating oil additive, owing to its free phosphorus and sulfur elements characteristics. Originality/value – Oil-soluble surface-modified Cu nanoparticles without phosphorus and sulfur were synthesized and its tribological properties as lubricating oil additives were also investigated in this paper. These results could be very helpful for application of Cu nanoparticles as environment-friendly lubricating oil additives.


Nano Futures ◽  
2021 ◽  
Author(s):  
Xin Kuang ◽  
Bifeng Yin ◽  
Xiping Yang ◽  
Hekun Jia ◽  
Bo Xu

Abstract This paper is to evaluate and compare the tribological properties of lubricating oil blends added with nano graphene and lubricating oil blends added with cerium oxide (CeO2) on the key friction pairs of the diesel engines. The dispersion stability is the premise of studying the tribological properties. In this paper, nano-CeO2 particles were self-made and high-quality nano-graphene was purchased. The dispersion stability of the two nanomaterials in lubricating oil was studied after the same modification respectively. According to the working conditions of the cylinder liner and the piston ring, the friction and wear tests of the lubricating oil blends added with the modified nanomaterials were carried out at the different temperatures. The results showed that the oleic acid and the stearic acid modified the two nanomaterials successfully. The dispersion stability of the modified nanomaterials in lubricating oil was improved. The dispersion stability of the lubricating oil blends added with graphene before and after modification was slightly higher than that of lubricating oil blends added with CeO2 before and after modification, respectively. At the high temperature, the anti-friction property of the two nano lubricating oil blends was similar. At the ambient temperature, lubricating oil blends added with modified CeO2 did not play a role in reducing friction, while lubricating oil blends added with modified graphene had the effect of reducing friction. Whether at ambient temperature or at the high temperature, the anti-wear property lubricated with lubricating oil blends added with modified CeO2 within the right concentration range was better than that lubricated with lubricating oil blends added with modified graphene.


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