STRESSED-DEFORMED STATUS OF THE HANGING HYDROCYLINDER: INFLUENCE OF THE CONJUGATED ELEMENTS’ PAIRS

Introduction. The contact interaction of the associated elements of the hydraulic cylinder (piston with sleeve, guide sleeve with cylinder and rod) determines the reliability of the reciprocating hydraulic motor. Assessing the effect of gaps of articulated hydraulic cylinder elements is an urgent task in view of the fact that the formation of gaps is inevitable, since friction is always accompanied by tribological wear processes. The paper investigates the determination and assessment of the influence of the gaps of the hydraulic cylinders’ mating elements on the stress-strain state of the contacting bodies on the example of the hydraulic cylinder for the Sokol 80.01 railway crane.Materials and methods. The author used the finite element method implemented in the Simulation SolidWorks module. Moreover, the author applied the Huber–Mises criterion as a criterion for the material plasticity. The paper also considered theoretically possible spatial design schemes of loading and depending on the type of the mating elements’ contacting of the hydraulic cylinder.Results. As a result, the author presented plots and graphical dependences, which were three-dimensional surfaces constructed according to the results of numerical experiments. The calculations took into account the joint deformation of the piston, sleeve, rod, guide sleeve and supporting guide rings of the hydraulic cylinder. The author carried out the analysis of the obtained diagrams and dependences of the contact interaction of the hydraulic cylinder for various options of the elements contacting. The paper presented the results that were useful for studying all types of hydraulic cylinders and working equipment of the road, construction and hoisting-andtransport machines.Financial transparency: the author has no financial interest in the presented materials or methods. There is no conflict of interest.

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NUMERICAL CALCULATION OF THE HYDROLIQUID LEAKAGE THROUGH THE RADIAL CLEARANCE OF THE CONNECTED ELEMENTS ON THE TOWER CRANE HYDROCILINDER

The Russian Automobile and Highway Industry Journal ◽

10.26518/2071-7296-2019-1-18-30 ◽

2019 ◽

Vol 16 (1) ◽

pp. 18-30

Author(s):

D. A. Potakhov ◽

Ya. S. Vatulin

Keyword(s):

Numerical Calculation ◽

Three Dimensional ◽

Flow Simulation ◽

Road Construction ◽

Physical Nature ◽

Hydraulic Cylinder ◽

Radial Clearance ◽

The Road ◽

Tower Crane ◽

Hydraulic Cylinders

Introduction. The authors present the numerical calculation of the hydro-liquid leakage throughthe radial clearance of the “piston - hydraulic cylinder” conjugate node on the basis of determiningthe sealing elements’ resource of the tower crane hydraulic cylinder.Materials and methods. The authors use the method of mathematical modeling, which makes it possible to model the containing elements’ interaction of different physical nature on the unified methodological basis. Moreover, the paper presents such simulation systems as Simulation (finite element method), Flow Simulation (finite volume method) of the SolidWorks CAD program and Simulink Matlab with expansion packs.Results. As a result, the authors demonstrate the three-dimensional and irregular cross-section conjugation model of the radial clearance in the “piston - hydraulic cylinder” conjugate node. In addition, the authors propose the calculating method of the hydraulic cylinder tightness. Such method establishes the following scheme: “load on the hydraulic cylinder —number of operating cycles — uneven radial clearance between the piston and the liner — amount of fluid leakage — shrinkage of the rod”.Discussion and conclusions. The results of the research make it possible to increase the reliability of the power hydraulic cylinders of the road construction machines and equipment.

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Three Dimensional Seismic Isolation System Using Hydraulic Cylinder

Seismic Engineering, Volume 2 ◽

10.1115/pvp2002-1429 ◽

2002 ◽

Author(s):

Shinichiro Kajii ◽

Naoki Sawa ◽

Nobuhiro Kunitake ◽

K. Umeki

Keyword(s):

Seismic Isolation ◽

Three Dimensional ◽

Vertical Direction ◽

Hydraulic Cylinder ◽

Seismic Load ◽

3D Seismic ◽

Isolation System ◽

Response Characteristics ◽

Seismic Motion ◽

Hydraulic Cylinders

A three-dimensional (3D) seismic isolation system for FBR building is under development. The proposed vertical isolation system consists form hydraulic cylinders with water-based liquid and accumulators to support large vertical static load and to realize low natural frequency in the vertical direction. For horizontal isolation, laminated rubber isolator or sliding type isolator will be combined. Because the major part of the feasibility of this isolation system depends on the sealing function and durability of the hydraulic cylinder, a series of feasibility tests of the hydraulic cylinder have been conducted to verify the reliability against seismic load and seismic motion. This paper describes the specification of the seismic isolations system, seismic response characteristics and the results of the feasibility tests of the seal. This study was performed as part of a government sponsored R&D project on 3D seismic isolation.

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Experimentally Validated Models of O-Ring Seals for Tiny Hydraulic Cylinders

ASME/BATH 2014 Symposium on Fluid Power and Motion Control ◽

10.1115/fpmc2014-7825 ◽

2014 ◽

Author(s):

Jicheng Xia ◽

William K. Durfee

Keyword(s):

Simulation Models ◽

Hydraulic Cylinder ◽

Operating Conditions ◽

System Level ◽

Needle Valve ◽

Hydraulic Systems ◽

System Level Simulation ◽

Piston Seal ◽

Cylinder Piston ◽

Hydraulic Cylinders

To enable simulation of tiny hydraulic systems, including predicting system efficiency, it is necessary to determine the effect of the hydraulic cylinder piston seal. For tiny cylinders whose bore is less than 10 mm, O-ring seals are convenient. Simplified models for the O-ring were used to describe piston leakage and friction and based on the models, the force and volumetric efficiencies for tiny cylinders were predicted for a range of steady state operating conditions. To validate the models, a test stand was constructed to collect experimental data for 4, 6 and 9 mm bore cylinders, which were in the form of a vertical ram with a single O-ring seal. The ram was fully extended and put under load. A needle valve was then cracked to cause the ram to descend at different speeds. Pressure, load and velocity were recorded and the data used to calculate cylinder efficiencies, which were then compared to model predictions. The model and the experiment showed essentially zero leakage. The experimental force efficiency had good agreement with the model over a range of operating conditions. The study showed that simple O-ring models for tiny hydraulic cylinders suffice for building system level simulation models.

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A Technological and Typological Analysis of Lithic Material from Skovmosen I, Denmark

Danish Journal of Archaeology ◽

10.7146/dja.v8i0.112232 ◽

2019 ◽

Vol 8 ◽

pp. 1-18 ◽

Cited By ~ 1

Author(s):

Thomas Eggers-Kaas ◽

Jesper Borre Pedersen ◽

Christian Steven Hoggard ◽

Florian Sauer ◽

Jan Hilgart ◽

...

Keyword(s):

Three Dimensional ◽

Road Construction ◽

Digital Recording ◽

Construction Work ◽

Assemblage Composition ◽

The Road ◽

Work Material ◽

Primary Reduction

During road construction work, material attributed to the Final Palaeolithic was discovered at Skovmosen I, near Kongens Lyngby on Zealand, eastern Denmark. Although it is regularly mentioned in reviews of the southern Scandinavian Final Palaeolithic, the Skovmosen I assemblage has hitherto remained poorly described. We here review the site’s discovery history and its context. Aided by a three-dimensional digital recording protocol, this article details the assemblage composition and its technology. The assemblage is comprised of tanged points, scrapers and burins, alongside blades and cores as primary reduction products. Although evidently disturbed by the road construction that led to the site’s discovery, the material likely reflects the remains of a small Final Palaeolithic locale, where diverse activities were carried out.

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Mathematical models of wheel turning processes road construction vehicles

Nauchno-tekhnicheskiy vestnik Bryanskogo gosudarstvennogo universiteta ◽

10.22281/2413-9920-2021-07-03-259-269 ◽

2021 ◽

Vol 7 (3) ◽

pp. 259-269

Author(s):

R.Yu. Sukharev ◽

Keyword(s):

Mathematical Models ◽

Control Systems ◽

Three Dimensional ◽

Road Construction ◽

Control Effect ◽

Vertical Coordinate ◽

The Road ◽

Wheel Turning ◽

Multi Stage ◽

Construction Machine

The construction of highways is a complex, multi-stage process. Most of the construction works are carried out according to the projects of structures and quite high requirements are imposed on the quality of execution. The fulfillment of these requirements is associated with great difficulties in view of the limited accuracy of the road construction machine itself, the lack of on-board control systems and the limited capabilities of the human operator, who is unable to determine the required exact parameters of the structure being built «by eye». To meet the requirements, three-dimensional control systems are used, which allow determining 3 coordinates of the working order of the machine – the vertical coordinate and the location of the machine on the construction site. At the same time, the digital project of the constructed structure should be the setter in such a system. The system determines the current position and compares it with the project. On the basis of this information, a control effect on the operating organ of the machine is formed. The course of movement and the speed of the machine when using such systems are determined by the machine operator. Further development of these systems should be four-dimensional systems – in which all control actions are assigned to the control system, starting from calculating the trajectory of the machine, choosing the speed, determining the required number of passes and ending with controlling the position of the working body of the machine at each moment of time. For the functioning of these systems, adequate mathematical models of the turning processes of road construction machines with different steering options are necessary.

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The Selection of Hydraulic Cylinder using multi-attribute decision-making methods

10.21203/rs.3.rs-1023928/v1 ◽

2021 ◽

Author(s):

Satywan Khatke ◽

Satyam Fulzele ◽

Shubham Kadam ◽

Avinash Kamble

Keyword(s):

Decision Making ◽

High Pressure ◽

Manufacturing Industry ◽

Hydraulic Cylinder ◽

Hydraulic Motor ◽

Current Case ◽

Hydraulic Cylinders ◽

Multi Attribute Decision Making ◽

Selection Methodology ◽

Selection Of

Abstract A hydraulic cylinder has an important role in the manufacturing industry for producing unidirectional force through the unidirectional direction. Generally, hydraulic cylinders are used where high-pressure applications are required. It is also called a linear hydraulic motor or mechanical actuator. It is manufactured with closer precisions; thus, it involves higher costs and also, it is desired that hydraulic cylinder work as mentioned design. The main purpose of a hydraulic cylinder is to apply force unidirectional with high pressure. The selection of appropriate Hydraulic Cylinders is a critical task for designers. Designers need to find out precise and required properties of it to fulfil industry demand with desired specifications. Different cylinders possess different properties, so by using an optimization tool we can solve such problems. A systematic approach must be used for the selection of hydraulic cylinders. Thus, in current case study work concentrate on the selection methodology for the best Hydraulic cylinder using four different multi-attribute decision-making methods. The decision-making methods help to predict and rank different hydraulic cylinders.

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Improving the efficiency of dispersed preparatory and excavation works in road construction using bulldozers with universal worker equipment

Russian journal of transport engineering ◽

10.15862/31sats319 ◽

2019 ◽

Vol 6 (3) ◽

Author(s):

Nikolai Tokar ◽

Zelgedin Mevlidinov ◽

Tatiana Levkovich ◽

Alexandr Foevtsov

Keyword(s):

Road Construction ◽

Hydraulic Cylinder ◽

The State ◽

Back Side ◽

Technological Capabilities ◽

Construction Organizations ◽

Metal Sheets ◽

Hydraulic Cylinders ◽

The University ◽

The City

The work is devoted to ways to improve the efficiency of preparatory and excavation works in road construction using bulldozers equipped with universal working equipment. Studying the state of the bulldozer Park of road construction organizations of the city of Bryansk and the Bryansk region, it was revealed that the Park contains obsolete bulldozers. In this paper, the authors proposed options for improving the university of the working equipment of the bulldozer with the addition of a controlled knife system or controlled lower sections. At the equipment-driven knife system, the working equipment of the bulldozer is characterized in that the edges of the bottom of the blade of the inserted knife system imposed on the surface of the blade, consisting of metal sheets with cutting edges, stiffeners and connected to gidrol linkami their management by means of brackets , and with a blade – with the help of duosonics, hydraulic cylinders control the cutter systems, BAP-pyatsya the edges on the back side of the blade with eyes limited to residing their turn to increase the rigidity of the structure. If necessary, the cutting knives can be replaced with a cargo fork to effectively pick up the goods. When the equipment controlled the lower sections of the working equipment is characterized in that the push bars have cutouts for the installation of cross beam and pivotally connected via axles to the main building-som of the blade, which has a pivotally mounted visor with snarling face and eyes with hydraulic cylinder control. The lower sections are connected to the lever by means of hinge rods. The expansion of technological capabilities is achieved through the installation of an additional module-a loosening tooth with a tip or a cargo fork.

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Rockfall on the Slope of the Embankment of Finite Element Analysis of the Impact of the Impact

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.261-263.1119 ◽

2011 ◽

Vol 261-263 ◽

pp. 1119-1123

Author(s):

Zi Jian Wang ◽

Sheng Xie Xiao

Keyword(s):

Finite Element ◽

Large Scale ◽

Three Dimensional ◽

Road Construction ◽

General Purpose ◽

Simulation Software ◽

Initial State ◽

Element Analysis ◽

The Road ◽

The Impact

This article in a typical road slope model as an example, through large-scale general-purpose finite element simulation software ANSYS/LS-DYNA rockfall on the slope of the roadbed impact for three-dimensional dynamic analysis in the roadbed, slope geological parameters and falling stone initial state is not at the same time on the roadbed impact the results of comparative analysis. The result is the mountain slope of the road construction project provides reference.

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Tribological Behavior of Hydraulic Cylinder Coaxial Sealing Systems Made from PTFE and PTFE Compounds

Polymers ◽

10.3390/polym12010155 ◽

2020 ◽

Vol 12 (1) ◽

pp. 155

Author(s):

Andrea Deaconescu ◽

Tudor Deaconescu

Keyword(s):

Film Thickness ◽

Working Conditions ◽

Tribological Behavior ◽

Hydraulic Cylinder ◽

Current Trends ◽

Cylinder Piston ◽

Hydraulic Cylinders ◽

Fluid Film Thickness ◽

Selection Of

Current trends concerning hydraulic cylinder sealing systems are aimed at decreasing energy consumption which can be materialized by minimizing leaks and reducing friction. The latest developments in the field of materials and sealing system geometries as well as modern simulation possibilities allow maximum performance levels of hydraulic cylinders. Reducing friction is possible by hydro-dynamic separation of the sliding and sealing points already at very low velocities and by using materials, such as plastomers, from polytetrafluoroethylene (PTFE) (virgin PTFE and filled PTFE). It is within this context that this paper discusses a theoretical and experimental study focused on the tribological behavior of coaxial sealing systems mounted on the pistons of hydraulic cylinders. It presents a methodology for the theoretical determination of the lubricant film thickness between the cylinder piston and the seal. The experimental installation used for measuring fluid film thickness is presented, and the results obtained under various working conditions are compared to the theoretical ones. For the analyzed working conditions related to pressure, speed, and temperature, the paper concludes with a set of criteria for the selection of the optimum seal material so as to maximize energy efficiency.

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