Petroleum and related products. Determination of the corrosion resistance of fire-resistant hydraulic fluids

The corrosion resistance of fly ash-based geopolymer structural concrete (GPC), with or without fibers, was investigated in a simulated marine environment, and compared with that of ordinary Portland cement structural concrete. The corrosion behavior is studied through an electrochemical method for inducing accelerated corrosion. The fiber-reinforced specimens contained polyolefin fibers in the amounts of 0.1%, 0.3%, and 0.5% by volume. Several artificial corrosion conduits were introduced into the specimens reaching up to the rebars. This process enhanced the rate of laboratory corrosion in GPC. The corrosion-damaged beams were then analyzed through a method of crack scoring, and determination of steel mass loss and residual flexural load capacity. The fiber-reinforced corroded GPC beams showed a 24% reduction in crack scores, and a 109% increase in residual flexural load capacity, compared to unreinforced corroded GPC beams. This shows promise of fiber-reinforced GPC as a sustainable structural material in the marine environment.

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Application of Multidimensional Statistical Analysis in Tribotechnical Diagnostics of Hydraulic Fluids in Woodworking Equipment

Materials ◽

10.3390/ma14164628 ◽

2021 ◽

Vol 14 (16) ◽

pp. 4628

Author(s):

Michaela Hnilicová ◽

Ján Turis ◽

Richard Hnilica

Keyword(s):

Data Matrix ◽

Multivariate Statistical Methods ◽

Multivariate Statistical ◽

Machine Maintenance ◽

Hydraulic Fluids ◽

Quantitative Characteristics ◽

Friction Surfaces ◽

Qualitative And Quantitative Characteristics

The article dealt with the assessment of the quality of hydraulic oil and determination of the mode of wear of the friction surfaces of Baljer & Zembrod manipulating lines through the information traces in the oils by applying tribotechnical diagnostics. We presented the assessment of the level of degradation of the oils. In addition, we presented the mode of wear of the friction surfaces washed in oil through evaluation of the qualitative and quantitative characteristics of the particles found in the oil. In detail, we focused on the application of suitable multivariate statistical methods on the data matrix. The article also presents predictive models that can sort oils into groups based on the assessment of quality of the oil and the state of the friction couples. The models can be used in research and in solving practical tasks in tribotechnical diagnostics of hydraulic fluids in woodworking equipment. Our results showed that the manipulation lines were greatly thermically stressed due to inadequate oil and machine maintenance. By correlative integration of all methods used, we could determine the real mode of the wear of the tribologic nodes of the machine. The experiment enabled the early detection of an undesirable process in the tribological node and implementation of corrective measures before the machine would break down.

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