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Lubrication of Distribution Electrical Equipment
Published in Bella H. Chudnovsky, Electrical Power Transmission and Distribution, 2017
Penetrating oil should not be used as a lubricant in electrical equipment. Penetrating oil is not designed for lubrication; it always contains solvent(s). Penetrating oil works only briefly, is contaminated easily, and may change into a viscous mess. In comparison with grease, penetrating oil has much lower viscosity (flows easily), very low boiling temperature and high vapor pressure at ambient temperature. It will leak out under gravity or centrifugal action, leaving the lubricated parts dry. Penetrating oil will attack, dissolve, and wash out factory-installed lubricants and hasten failure. Most penetrating oils or aerosols are flammable and should not be applied in areas where sparks or arcing may occur. Penetrating oils are recommended only for rust removal and ease of part disconnection.
Lubrication of Distribution Electrical Equipment
Published in Bella H. Chudnovsky, Transmission, Distribution, and Renewable Energy Generation Power Equipment, 2017
Penetrating oil should not be used as a lubricant in electrical equipment. Penetrating oil is not designed for lubrication; it always contains solvent(s). Penetrating oil works only briefly, is contaminated easily, and may change into a viscous mess. In comparison with grease, penetrating oil has much lower viscosity (flows easily), very low boiling temperature, and high vapor pressure at ambient temperature. It will leak out under gravity or centrifugal action, leaving the lubricated parts dry. Penetrating oil will attack, dissolve, and wash out factory-installed lubricants and hasten failure. Most penetrating oils or aerosols are flammable and should not be applied in areas where sparks or arcing may occur. Penetrating oils are recommended only for rust removal and ease of part disconnection.
Plasma sprayed α-Al2O3 main phase coating using γ-Al2O3 powders
Published in Surface Engineering, 2019
Bolong Niu, Li Qiang, Junyan Zhang, Fan Zhang, Yong Hu, Wei Chen, Aimin Liang
In this research, alumina coatings were produced by DH-2080 plasma spraying equipment (Shanghai Dahao Nanomaterial Spraying Ltd. China). A mixture of argon and hydrogen was used as the plasma gas. A neutral alumina powders whose main phase is γ-Al2O3 were employed as original crude materials. We designed two current series of process parameters in the study, and the details of various spraying process parameters are listed in Table 1. To easily compare the mechanical properties of the coatings prepared under different process conditions, the thickness of each coating (Nos. 1–6) was controlled at 0.10±0.01 mm by controlling spraying scanning times. The alumina coatings were deposited on 45# steel blocks with a height of 8 mm and a diameter of 24 mm. Before plasma spraying, the steel substrates were degreased ultrasonically in acetone and sandblasted with corundum. The surface roughness of the alumina coatings was measured by model 2206 surface roughness measuring instrument (Harbin Measuring & Cutting Tool Factory, China). The porosity of the alumina coatings in our research can be calculated by weighing coating mass before and after penetrating olefin oil separately according to the formula p(%)=(m2–m1)/(ρV)×100%, where p, m1, m2, ρ and V represent coating porosity, coating mass before penetrating oil, coating mass after penetrating oil, oil density and coating apparent volume, respectively. The microhardness (HV) of the coatings was tested by model MH-5-VM microhardness tester (Shanghai Hengyi Technology Company, China) with 500 g load for a holding time of 5 s. The hardness test was performed on the surfaces of the coatings and the microhardness value taken for the alumina coating was the average value for the parallel measuring of five times. The tribological performance of the alumina coating was examined by SRV-IV microvibration friction and wear tester (OPTIMOL, Germany) with olefin as the lubricant oil. GCr15 steel balls of Φ10 mm were used as friction counterparts. The friction and wear test was conducted at room temperature (∼25°C), a load of 10 N, a microvibration friction frequency of 25 Hz and a microvibration amplitude of 1 mm for 30 min. The surface morphology of the alumina coating was observed by an SEM (TESCAN MIRA3 FEG, Chech) and an Olympus optical microscopy (Olympus Corporation, Japan) separately. The wear track observation and its Energy Dispersive Spectrometer (EDS) analysis of the alumina coating were performed by the SEM (TESCAN MIRA3 FEG, Chech).