Hydraulic Fluid Research Articles

Ionic Hydraulic Fluids and Seal-Material Compatibility

Manufacturers of hydraulic fluids invest a lot of effort and resources in improving their physico-chemical properties, with the goal of getting as close as possible to the properties of an ideal hydraulic fluid. It should be non- flammable, environmentally friendly, sustainable and should have excellent physical and chemical properties. After decades of development in the field of ionic liquids and the search for an ionic liquid suitable for use in hydraulic systems, ionic hydraulic liquids are now already in industrial use, especially on devices that operate in harsh and risky operating conditions. Since ionic hydraulic fluids are a completely new type of hydraulic fluid, one of the issues is their compatibility with the materials present in the hydraulic components, including all the seals. This paper refers to the process of testing the compatibility of hydraulic seal materials with different types of ionic hydraulic fluids according to the standardized percentages and recommendations, with emphasis on changes in the swell, shrinkage and hardness of the seals. The presented results are a useful guide for selecting suitable seal materials in case of using high-tech ionic hydraulic fluids.

Integrated Systems of a Solar Thermal Energy Driven Power Plant

Integrated Systems of a Solar Thermal Energy Driven Power Plant

PILOT TESTING AND ASSESSMENT OF MICROBIAL CONTAMINATION OF HYDRAULIC FLUID BASED ON HYDROTOL-ITCH HFAE CONCENTRATE FOR HYDRAULIC SYSTEMS OF POWERED MINE SUPPORTS

Pilot-scale test results and laboratory studies of fire-resistant hydraulic fluid based on the developed hydraulic concentrate Hydrotol-ITCh HFAE are presented. Stable operation and operating parameters preservation of the developed hydraulic fluid physicochemical properties under the real conditions on a contaminated hydraulic system of a mining industry enterprise are shown. It was found that during six months of operation, the range of pH values, electrical conductivity, concentration and bacteriological purity did not change significantly, while the concentrate refilling, as well as the use of special disinfectants and cleansers, was not required. For the first time, the microbial composition of hydraulic fluid exposed to operation in the powered supports of the enterprise was studied using the method of metagenomic sequencing. Molecular genetic methods revealed a wide range of bacterial associates with various types of metabolism, including anaerobic sulphate-reducing bacteria involved in the biological corrosion of metals.

An Optimal Model for Determination Shut-In Time Post-Hydraulic Fracturing of Shale Gas Wells: Model, Validation, and Application

The global shale gas resources are huge and have good development prospects, but shale is mainly composed of nanoscale pores, which have the characteristics of low porosity and low permeability. Horizontal drilling and volume fracturing techniques have become the effective means for developing the shale reservoirs. However, a large amount of mining data indicate that the fracturing fluid trapped in the reservoir will inevitably cause hydration interaction between water and rock. On the one hand, the intrusion of fracturing fluid into the formation causes cracks to expand, which is conducive to the formation of complex fracture networks; on the other hand, the intrusion of fracturing fluid into the formation causes the volume expansion of clay minerals, resulting in liquid-phase trap damage. At present, the determination of well closure time is mainly based on experience without theoretical guidance. Therefore, how to effectively play the positive role of shale hydration while minimizing its negative effects is the key to optimizing the well closure time after fracturing. This paper first analyzes the shale pore characteristics of organic pores, clay pores, and brittle mineral pores, and the multi-pore self-absorption model of shale is established. Then, combined with the distribution characteristics of shale hydraulic fracturing fluid in the reservoir, the calculation model of backflow rate and shut-in time is established. Finally, the model is validated and applied with an experiment and example well. The research results show that the self-imbibition rate increases with the increase in self-imbibition time, and the flowback rate decreases with the increase in self-imbibition time. The self-imbibition of slick water is the maximum, the self-imbibition of breaking fluid is the minimum, and the self-imbibition of mixed fluid is the middle, and the backflow rates of these three liquids are in reverse order. It is recommended the shut-in time of Longmaxi Formation shale is 17 days according to the hydration and infiltration model.

Problems of transition of Russia’s energy sector to using domestically produced fire-resistant fluids

Fire-resistant fluids and lubricants are products that are used in various industries or energy sector to ensure the reliability and safety of equipment operating under high temperature and pressure conditions. Aspects of the use of fire-resistant fluids (hydraulic or lubricating agents), including those based on xylenol, in the Russian Federation energy industry (control and lubrication systems for automatic control systems of steam or gas turbines), and the problems of switching from imported materials to domestic analogues are considered. The range of issues raised at the All-Russian Scientific and Technical Conference “Modern trends in the development of the market for fire-resistant turbine oils and the record of their operation at thermal power plants and nuclear power plants,” held in March 2023, as well as the decisions made there, are covered. Besides, measures taken by energy companies to legitimize the use of domestic fire-resistant fluids for operation in thermal power equipment in Russia are indicated. The results of laboratory studies of new domestic fire-resistant fluids are presented, conclusions are drawn about the possibility of use, operation, and approval of new domestic lubricating or hydraulic fluids in the energy sector. The article was prepared in cooperation between two large electric-heat-generating companies and with the participation of Power Machines, PJSC. One of the goals set by the authors was to promote the production of domestic fire-resistant fluids synthesized from raw materials available in the Russian Federation, ensuring the reliable functioning of oil systems of turbine units.

ANALYSIS OF THE POSSIBILITY OF APPLICATION OF HYDRAULIC MOTOR-WHEELS IN TRANSMISSIONS HIGH-SPEED TRACTORS

Goal. The purpose of the article is to assess the possibility of developing a hydraulic fluid power in accordance with the standard traction-speed characteristics of the KhTZ-17021 wheeled tractor with the of using gearless drives of the driving wheels. For this purpose, the calculation of the hydraulic fluid power of the wheeled tractor was performed when using the latest radial piston multi-cycle hydraulic motor-wheels with a wide range of rotation frequency and adjustment of the working volume. Research methodology. An analysis of the traction-speed characteristics of the KhTZ- 17021 wheeled tractor and, based on it, a review of modern high-torque radial-piston multi-cycle hydraulic motors from the point of view of meeting the characteristics of torque and rotation frequency with power limitations relative to the serial model in the full speed range of the tractor. The maximum values of the working volumes of the 4 driving hydraulic motor-wheels and the power supply pump of these hydraulic motors, the torque and pressure drop in the hydraulic drive are calculated, and the modes in which it is necessary to change the working volume of the hydraulic motors from the maximum to the minimum values to work out the traction-speed characteristics. A comparative analysis of radial-piston multi-cycle hydraulic motors was carried out, and for the hydromotor-wheel model MHP27 of the "Poclain Hydraulics" company, which was chosen for the study, the hydraulic principle diagrams were considered with the use of a hydraulic regulation system of four stages of the working volume in hydraulic motors, the use of combined parking and service brakes, as well as an anti-skid system using means of proportional electro-hydraulic automation. The results. High-torque hydraulic motor-wheels of the radial piston type were selected, which make it possible to ensure the operation of the tractor transmission without intermediate gearboxes between the hydraulic motors and wheel hubs, and the calculated value of the working volume of the axial piston pump, which ensures the operation of the tractor transmission in the full speed range. Based on the results of the calculations, it was established that the pressure in the hydraulic drive does not exceed 35 MPa, while values from 40 MPa to 50 MPa are achieved in modern pumps and hydraulic motors. The possibility of increasing the speed of the tractor from standard 35 km/h to promising 50 km/h is shown.

Hydrogeochemistry and indicators of flowback and produced water from wells that are hydraulically fractured with recycled wastewater: A case study of the Changning gas field in the Sichuan Basin

With the increasing number of shale gas wells being hydraulically fractured with recycled flowback and produced water to reduce the consumption of fresh water, geochemical indicators of hydraulic fracturing flowback fluids (HFFFs) from such wells need to be found to evaluate the potential pollutants caused by shale gas development. To fill this knowledge gap, we analysed 64 HFFF samples from 3 Changning wells (fracked with recycled wastewater) to form a time series and compared them to HFFF samples from 3 Weiyuan wells (fracked with fresh water). We also made comparisons of HFFFs from two types of wells in the Appalachian Basin with reported data. The results indicated that regardless of the fracturing fluid being used, the water‒rock reaction caused by the hydraulic fracturing process resulted in the release of exchangeable phase elements, such as lithium, boron, with relatively depleted δ7Li and δ11B, and strontium with relatively enriched 87Sr/86Sr values on the shale surface, into the HFFFs. The composition of the injected fracturing fluid affected the strength of the water‒rock reaction, but the effect is negligible, as the fracturing process can still form the unique Sr, Li, and B isotope ratios of the HFFF. Thus, the elemental signatures (B/Cl and Sr/Cl) and isotopic fingerprints (δ11B, δ7Li, and 87Sr/86Sr) derived from HFFFs can be used to distinguish between HFFFs from wells hydraulically fractured by either fresh water or recycled wastewater and flowback water from conventional oil and gas wells. The results are important for the environmental evaluation of the large number of wells being fracked with recycled wastewater each year.

Study of the Interaction of a Hydraulic Fracture with a Natural Fracture in a Laboratory Experiment Based on Ultrasonic Transmission Monitoring

This paper presents the results of experiments on the study of a hydraulic fracture’s interaction with a preexisting fracture. A distinctive feature of the conducted experiments is the ability to use ultrasonic transmitting monitoring to measure the fracture propagation and opening simultaneously with the pore pressure measurements at several points of the porous saturated sample. It allows us to obtain the pressure distributions at various experiment stages and to establish a relation between the pore pressure distribution and hydraulic fracture propagation and its interaction with macroscopic natural fractures. The possibilities of active ultrasonic monitoring have been expanded due to preliminary calibration experiments, which make it possible to estimate the fracture opening via attenuation of ultrasonic pulses. The experiment demonstrated the most complex scenario of fracture interactions when a hydraulic fracture intersected with a natural fracture and the natural fracture in the vicinity of the intersection was also opened. The additional complications arise from fracture arrangement: the hydrofracture was normal with respect to the base plane, while the natural fracture was slanted. This led to gradual growth of the intersection zone as the hydrofracture propagated. The experiments show that the natural fracture limited the fracture’s propagation. This was caused by the hydraulic fracturing fluid leaking into the natural fracture; thus, both the hydraulic fracture and natural fracture compose a united hydraulic system.

Investigation of tribological parameters of friction pairs during lubrication with hydraulic fluid and mineral oil

The paper presents the results of research on tribological parameters of friction pairs at lubrication with hydraulic fluid and mineral oil. Friction pairs BrPh6,5-0,15 and Hardcarb-TP with steel 40Х at lubrication with hydraulic fluid AMg-10 and mineral oil I20A have good tribological properties. At load 2,003 MPa, temperature 20 °C and speed 2,5 m/s the coefficient of friction does not exceed the value 0,1. It is not recommended to use hydraulic fluid AMg-10 at contact pressure 3500...5500 MPa, because the coefficient of friction is higher than 0.65. Industrial oil I20A provides low coefficient of friction 0.1-0.2 at these contact pressures.

Tribological studies of materials for sliding bearings when lubricated with hydraulic fluid

Tribological research of materials BrOPh6.5-0.15, PH4M paired with 40X steel and lubricated with hydraulic fluid AMh-10 showed good antifriction properties. The results of the research on the influence of load, speed and temperature on the coefficient of friction of materials: BrOPh6.5-0.15 and PH4M when lubricated with AMh-10 hydraulic fluid. At a load of 0.5447 MPa, the coefficient of friction of BrOPh6.5-0.15 material at a temperature of 90°C is 1.58 times higher, and at a load of 2.003 MPa, the coefficient of friction of BrOPh6.5-0.15 material is 2.85 times higher than the coefficient of friction of BrOPh6.5-0.15 material at a temperature of 20°C. Materials BrOPh6.5-0.15 and PH4M are promising for application in plain bearings of pumps pumping hydraulic fluid AMh-10.

Crystal structures of three uranyl-acetate-bipyridine complexes crystallized from hydraulic fracking fluid.

Hydraulic fracking exposes shale plays to acidic hydraulic fracking fluid (HFF), releasing toxic uranium (U) along with the desired oil and gas. With no existing methods to ensure U remains sequestered in the shale, this study sought to add organic ligands to HFF to explore potential U retention in shale plays. To test this possibility, incubations were set up in which uranyl acetate and one organic bipyridine ligand (either 2,2'-, 2,3'-, 2,4'-, or 4,4'-bipyridine) were added to pristine HFF as the crystallization medium. After several months and complete evaporation of all volatiles, bulk yellow crystalline material was obtained from the incubations, three of which yielded crystals suitable for single-crystal analysis, resulting in two novel structures and a high-quality structure of a previously described compound. The UO2VI acetate complexes bis(acetato-κ2O,O')(2,2'-bipyridine-κ2N,N')dioxidouranium(VI), [U(C2H3O2)2O2(C10H8N2)2] or [2,2'-bipyridine]UVIO2(CH3CO2)2, (I), and bis(acetato-κ2O,O')(2,4'-bipyridine-κN1')dioxidouranium(VI), [U(C2H3O2)2O2(C10H8N2)2] or [2,4'-bipyridine]2UVIO2(CH3CO2)2, (III), contain eight-coordinate UVI in a pseudo-hexagonal bipyramidal coordination geometry and are molecular, packing via weak C-H...O/N interactions, whereas catena-poly[bis(2,3'-bipyridinium) [di-μ-acetato-μ3-hydroxido-μ-hydroxido-di-μ3-oxido-hexaoxidotriuranium(VI)]-2,3'-bipyridine-water (1/1/1)], (C10H9N2)2[U3(C2H3O2)2O8(OH)2]·C10H8N2·H2O or {[2,3'-bipyridinium]2[2,3'-bipyridine][(UVIO2)3(O)2(OH)2(CH3CO2)2·H2O]}n, (II), forms an ionic one-dimensional polymer with seven-coordinate pentagonal bipyramidal UVI centers and hydrogen-bonding interactions within each chain. The formation of these crystals could indicate the potential for bipyridine to bind with U in shale during fracking, which will be explored in a future study via ICP-MS (inductively coupled plasma mass spectrometry) analyses of U concentration in HFF/bipyridine/shale incubations. The variation seen here between the molecular structures may indicate variance in the ability of bipyridine isomers to form complexes with U, which could impact their ability to retain U within shale in the context of fracking.

SBC-SNOLAB scintillation system and SiPM implementation for dark matter searches

The Scintillating Bubble Chamber (SBC) collaboration is constructing a 10 kg liquid argon (LAr) bubble chamber at SNOLAB called SBC-SNOLAB having the main objective of detecting dark matter. One of the most novel aspects of SBC-SNOLAB is the scintillation system, consisting of LAr doped with on the order of 10 ppm Xe, 48 FBK VUV silicon photomultipliers (SiPMs), the SiPM electronics, two quartz jars, and liquid CF4 used as an hydraulic fluid and additional source of scintillation photons. In contrast with traditional single or dual phase scintillation experiments, the collected LAr scitillation light is used to veto signals which involve the detection of at least a single photoelectron. These proceedings will describe in detail the current SBC-SNOLAB scintillation system which includes the unique design considerations for SBC-SNOLAB that limit the light collection efficiency and the electronics.

Friction of fluoroplastic with steel in a hydraulic fluid medium when transient mode

The article considers the issues of experimental research of the antifriction properties of fluoroplastic seals of piston pump hydraulic systems in a transient friction mode. The statement about the influence of frictional heating on the tribological properties of the seal is substantiated. Model experiments are used to study the friction coefficients at the moment of changing the direction of the contacting surfaces movement and the transient period from the moment of starting from a standstill to the steadystate friction mode. The experiments were carried out under conditions of heating the hydraulic fluid to the maximum temperature. Particular attention is paid to the change in the friction coefficient with increasing load-speed characteristics. The limiting contact pressures that ensure trouble-free operation of a seal made of radiation-modified fluoroplastic have been determined.

Проблемы и методы принятия решений на применение горюче-смазочных материалов в технике

Applied problems that restrain the enhancing of decision making objectiveness of fuels and lubricants use in equipment are shortly characterized. Several possibilities as to the theory of decision making application for the decision making of fuels and lubricants use in equipment are analyzed. Two methods are introduced and explained to make rational decisions based on integral evaluation criterions as well as on quantitative estimates of properties indicators of fuels and lubricants propensity for transformationsin equipment. In addition some simple illustrations of implementation of new methods with regards to diesel fuels and hydraulic fluids are provided.

Carbon-carbon composite material in friction units when lubricated with hydraulic fluid

The paper deals with the issues related to the friction of carbon-carbon composite against steel in the medium of hydraulic fluid. Variation of friction coefficient from load, speed and temperature is analyzed. Comparison of antifriction properties of Hardcarb TP material with fluoroplastic modified by radiation treatment is performed. It is established that under the conditions of the experiments, the carbon composite has a higher friction coefficient than the fluoroplastic, but acceptable (f = 0.12) for use in friction units. Hardcarb TP material is promising for application in sliding friction friction units in lubrication with AMg-10 working fluid under conditions of increased requirements for the reliability and service life of hydraulic pumps.

Intensification of oil production through the use of hydraulic fracturing fluid based on polyacrylamide

The article considers the technology of Hydraulic Fracturing (HF) based on polyacrylamide (Co-PAM), identifies parameters for evaluating the quality of the fluid both on a guar and polyacrylamide base. Fluid viscosity is a main criteria of success of HF operations. Thus, fluid thermal stability, determine the pumping time. The composition of the Co-PAM-based HF fluid differs from the guar-based one, consisting of two main chemical reagents - a gelling agent and a crosslinker(x-linker), in that only a synthetic gelling agent is used. Recommended concentration starts from 4 l/m3. At this concentration the synthetic gel starts to exhibit properties of a sand-carrying fluid, suitable for standard pump rate (4.0-5.0 m3/min) HF. A significant advantage is compliance with the requirements for HF fluids which not only improves the filtration properties of the formation but also considers the economic feasibility of using such a chemical reagent. Co-PAM gel using provides reduction of logistics costs, water heating. Also it allows to exclude hydration unit, reduced crew, decreased wear on pumping units, including reduced consumption of lubricants during the HF operation.

Performance Evaluation of Hydrostatic Transmission Systems in Tidal Energy Conversion

The growing need for renewable energy has brought oceancurrent energy’s promise as a consistent and ecologically benign source front stage. One can effectively harness this energy with tidal energy conversion systems (TECS). This work examined the performance of a hydrostatic transmission (HST) system in a prototype tidal stream power producing configuration. Comprising a turbine simulator, hydraulic transmission, and permanent magnet synchronous generator (PMSG) with torque, power, and speed sensors, the experimental setup Under different torque settings, tests were performed to assess if the system could separate submerged components from those above sea level and improve rotational speed. According to the findings, the HST system has rather poor efficiency, averaging about 22%, even as it delivers the intended speed gain. Efficiency loss results from elements including hydraulic fluid viscosity, internal wear, and shaft alignment. These results highlight the need of more study to maximize HST systems for improved dependability and performance in tidal energy uses.

РАСЧЕТ ЭНЕРГЕТИЧЕСКОГО БАЛАНСА МНОГОАГРЕГАТНОЙ ВЕТРОЭНЕРГЕТИЧЕСКОЙ УСТАНОВКИ В УСЛОВИЯХ НИЗКИХ СРЕДНЕПЕРИОДИЧЕСКИХ СКОРОСТЕЙ ВЕТРА

Energy supply of small facilities of the agro-industrial complex of Russia in remote rural areas using wind energy is an urgent task. Classical wind power plants operate efficiently at a wind speed of more than 7 meters per second, but in most of Russia such a wind speed is rare. Therefore, the utilization rate of the installed capacity of a wind farm is only 0.2. (Research Purpose) The research purpose is developing a method of increasing the utilization rate of the installed capacity of a wind farm and calculating its energy balance at average periodic wind speeds from 4 to 6 meters per second. (Materials and methods) To implement the proposed method, a multi-unit wind power plant consisting of wind receiving devices of various types driven by hydraulic pumps was used. As a result, the working fluid is feed into the hydraulic accumulating unit, from where the working fluid is fed to the hydraulic motor, which provides rotation of the generator shaft. (Results and discussion) At a wind speed of 4-11 meters per second, the total supply of the working fluid of all hydraulic pumps is greater than the required flow rate of the hydraulic pump. It was found out that in a typical period with an average periodic wind speed of 4-6 meters per second, the total volume of fluid supply by hydraulic pumps is 605.2; 758.0; 844.6 liters per hour, respectively. At the end of the period, 5.2 and 158.0 to 254.6 liters of liquid remain in the storage unit, which can compensate for calm periods up to 15-20 minutes. (Conclusions) The proposed method for increasing the utilization rate of the installed capacity of a wind power plant provides the required supply of hydraulic fluid at an average periodic wind speed of 4-6 meters per second, the annual utilization rate of the installed capacity of a wind power plant is 40-50 percent.

In vivo exposure to electronic waste (e-waste) leachate and hydraulic fracturing fluid adversely impacts the male reproductive system

Human health effects can arise from unregulated manual disassembly of electronic waste (e-waste) and/or hydraulic fracturing fluid spills. There is limited literature on the effects of e-waste and hydraulic fracturing wastewater exposure on the male reproductive system. Thus, this proof-of-concept study begins to address the question of how wastewater from two potentially hazardous environmental processes could affect sperm quality. Therefore, three groups of eight-week-old adult mice were exposed (5 d/wk for 6 wks) via a mealworm (Tenebrio molitor and Zophabas morio) feeding route to either: (1) e-waste leachate (50% dilution) from the Alaba Market (Lagos, Nigeria); (2) West Virginia hydraulic fracturing flowback (HFF) fluid (50% dilution); or, (3) deionized water (control). At 24-hours (hr), 3 weeks (wk), or 9-wk following the 6-wk exposure period, cohorts of mice were necropsied and adverse effects/persistence on the male reproductive system were examined. Ingestion of e-waste leachate or HFF fluid decreased number and concentration of sperm and increased both chromatin damage and numbers of morphological abnormalities in the sperm when compared to control mice. Levels of serum testosterone were reduced post-exposure (3- and 9-wk) in mice exposed to e-waste leachate and HFF when compared to time-matched controls, indicating the long-term persistence of adverse effects, well after the end of exposure. These data suggest that men living around or working in vicinity of either e-waste or hydraulic fracturing could face harmful effects to their reproductive health. From both a human health and economic standpoint, development of prevention and intervention strategies that are culturally relevant and economically sensitive are critically needed to reduce exposure to e-waste and HFF-associated toxic contaminants.

Experimental Investigation of Hydraulic Fracturing Fluid Based on Pseudo Gemini Surfactant with Polysaccharide Addition.

In the last decade, hydrogels for hydraulic fracturing based on viscoelastic surfactants have been actively studied. Interest in these systems is justified by their unique qualities: good viscoelasticity and the ability to form stable suspensions of proppant or sand, destruction without the formation of bridging agents, hydrophobization of the rock surface and metal of technological equipment, as well as oil-cleaning properties. These qualities are most often provided by a minimum set of components-a surfactant and an electrolyte. However, the absence of a polymer limits the use of these gels in formations where fluid leakoff is possible. In this article, a liquid was studied, based on a pseudo gemini surfactant (PGVES) with the addition of a water-soluble polysaccharide. The objects of study were selected based on the assumption of interactions between PGVES and the polymer; interactions which favorably influence the technological characteristics of the fracturing fluid. To confirm the hypothesis, rheological studies were carried out. These included rotational viscometry and oscillatory studies at various temperatures. The settling velocity of particles of various proppant fractions was studied and tests were carried out to assess fluid leakoff. The performed experiments show an improvement in the characteristics of the PGVES-based gel under the influence of the polysaccharide. In particular, the rheological properties increase significantly, the stability of proppant suspensions improves, and the fluid leakoff of systems decreases, all of which expands the possibility of using these fracturing fluids and makes this area of experimentation promising.