Vibration Behavior of Roll System under Nonlinear Constraints of the Hydraulic Cylinder

This study establishes a vertical–horizontal coupling vibration model of hot rolling mill rolls under multi-piecewise nonlinear constraints considering the piecewise nonlinear spring force and piecewise nonlinear friction force constraints of the hydraulic cylinder in the vertical direction of the rolls, the piecewise stiffness constraints in the horizontal direction, and the influence of the nonlinear dynamic rolling force in the rolling process. Using the average method to solve the amplitude–frequency response equation of the coupled vibration system and taking the actual parameters of a 1780 mm hot rolling mill (Chengde Steel Co., Ltd., Chengde, China) as an example, we study the amplitude–frequency characteristics of the mill rolls under different parameter settings. The results show that the amplitude and resonance region can be reduced by appropriately reducing the external disturbance force and the nonlinear spring force of the hydraulic cylinder, appropriately increasing the nonlinear friction force, and eliminating the gap between the bearing seat and the mill housing, to avoid the amplitude jump phenomenon due to piecewise variation. Furthermore, using the singularity theory to study the static bifurcation characteristics of the coupled vibration system, we establish a relationship between the vibration parameters and the topological bifurcation solution of the coupled system. The transition sets and their corresponding bifurcation topological structure in three cases are given, and the steady and unsteady process parameter regions of the rolls are obtained. The dynamic behavior of the coupled vibration system can be controlled by varying the bifurcation parameter. This study provides a theoretical basis for restraining the vibration of hot rolling mill rolls and optimizing the process parameters.

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Synergy of surface textures on a hydraulic cylinder piston

Micro & Nano Letters ◽

10.1049/mnl.2018.5535 ◽

2019 ◽

Vol 14 (4) ◽

pp. 424-429 ◽

Cited By ~ 1

Author(s):

Ying Zhang ◽

Liangcai Zeng ◽

Zhenpeng Wu ◽

Xianzhong Ding ◽

Kuisheng Chen

Keyword(s):

Hydraulic Cylinder ◽

Surface Textures ◽

Cylinder Piston

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Transient Property Improvement of Hydraulic Cylinder Control for Tunnel Boring Machine Using Opposite Reference Filter

IEEJ Transactions on Electronics Information and Systems ◽

10.1541/ieejeiss.140.320 ◽

2020 ◽

Vol 140 (3) ◽

pp. 320-325

Author(s):

Yoshihiro Ohnishi ◽

Takahisa Shigematsu ◽

Takuma Kawai ◽

Shinichi Kawamura ◽

Noboru Oda

Keyword(s):

Tunnel Boring Machine ◽

Hydraulic Cylinder ◽

Tunnel Boring

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Impact Assessment of Dynamic Characteristics on the Hydraulic Driven Machinery Operation

Mechanical Engineering and Computer Science ◽

10.24108/0418.0001354 ◽

2018 ◽

pp. 1-12

Author(s):

A. D. Terenteva

Keyword(s):

Dynamic Error ◽

Total Error ◽

Soil Layer ◽

Hydraulic Drive ◽

Hydraulic Cylinder ◽

Working Mechanism ◽

Automated Control ◽

Vertical Coordinate ◽

Construction Machinery ◽

The Difference

In civil engineering in Russia, trenching for utilities is currently under digging. To perform such works, it is necessary to use high-precision construction machinery, because inaccurate performance of works can lead to the break down of existing utilities, thereby affecting the residents of nearby houses and demanding the additional works for renewal.The most universal labour saver to perform construction works is hydraulic driven single-bucket excavators, which provide up to 38% of works. Therefore, to improve technical characteristics that affect the accuracy of the work performed is an important task.High requirements for the performance of works are defined by existing construction regulations: an allowable soil layer to remain is at most 0.05 m. To fulfil such requirements, an exact assessment of the working mechanism position and a trench profile is necessary.Examination of a manually operated digging process shows that an operator provides operations untimely, however an automated control system can solve this problem. Dynamic phenomena in the working mechanism have the greatest impact on the accuracy of the works performed.To assess the bucket digging edge position accuracy, a mathematical model of the working mechanism has been created. Based on the cycle scheme of the working process, the excessive displacements of the hydraulic cylinder rods under the load are taken into account. By the end of the cycle, the difference between the specified and obtained positions along the vertical coordinate has been 0.0892 m.A dynamic error of the hydraulic drive system of the working mechanism is considered as a sum of the error due to excessive displacements of the hydraulic cylinder rods and the error due to delay of the hydraulic drive, with the latter being calculated for the average time of delay taking into account the data available in the literature. The total error of the bucket digging edge position of the working mechanism is 0.1176 m, which is 2 times more than the value of 0.05 mConformity of all the links with specification requirements does not guarantee compliance with the required displacement accuracy of the bucket digging edge, and, thus, the soil layer to remain in the base of the trench can exceed the regulated value of 0.05 m.

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Calculating the Vibration Behavior of Continuous Structure Filled with Particles

50th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference ◽

10.2514/6.2009-2691 ◽

2009 ◽

Author(s):

Kyoko Masuda ◽

Kazuki Tsugihashi ◽

Akio Sugimoto

Keyword(s):

Continuous Structure ◽

Vibration Behavior

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Farmer suffers fatal crushing injuries when caught between a loader's hydraulic cylinder and its body frame.

10.26616/nioshsface93mn066 ◽

1994 ◽

Keyword(s):

Hydraulic Cylinder ◽

Body Frame

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A Theoretical Model with Which to Safely Optimize the Configuration of Hydraulic Suspension of Modular Trailers in Special Road Transport

Applied Sciences ◽

10.3390/app11010305 ◽

2020 ◽

Vol 11 (1) ◽

pp. 305

Author(s):

Rubén Escribano-García ◽

Marina Corral-Bobadilla ◽

Fátima Somovilla-Gómez ◽

Rubén Lostado-Lorza ◽

Ash Ahmed

Keyword(s):

Theoretical Model ◽

Wind Turbine ◽

Optimization Algorithm ◽

Hydraulic Cylinder ◽

Road Transport ◽

Automatic Testing ◽

Transport Systems ◽

The Road ◽

Proposed Model ◽

On The Road

The dimensions and weight of machines, structures, and components that need to be transported safely by road are growing constantly. One of the safest and most widely used transport systems on the road today due to their versatility and configuration are modular trailers. These trailers have hydraulic pendulum axles that are that are attached in pairs to the rigid platform above. In turn, these modular trailers are subject to limitations on the load that each axle carries, the tipping angle, and the oil pressure of the suspension system in order to guarantee safe transport by road. Optimizing the configuration of these modular trailers accurately and safely is a complex task. Factors to be considered include the load’s characteristics, the trailer’s mechanical properties, and road route conditions including the road’s slope and camber, precipitation and direction, and force of the wind. This paper presents a theoretical model that can be used for the optimal configuration of hydraulic cylinder suspension of special transport by road using modular trailers. It considers the previously mentioned factors and guarantees the safe stability of road transport. The proposed model was validated experimentally by placing a nacelle wind turbine at different points within a modular trailer. The weight of the wind turbine was 42,500 kg and its dimensions were 5133 × 2650 × 2975 mm. Once the proposed model was validated, an optimization algorithm was employed to find the optimal center of gravity for load, number of trailers, number of axles, oil pressures, and hydraulic configuration. The optimization algorithm was based on the iterative and automatic testing of the proposed model for different positions on the trailer and different hydraulic configurations. The optimization algorithm was tested with a cylindrical tank that weighed 108,500 kg and had dimensions of 19,500 × 3200 × 2500 mm. The results showed that the proposed model and optimization algorithm could safely optimize the configuration of the hydraulic suspension of modular trailers in special road transport, increase the accuracy and reliability of the calculation of the load configuration, save time, simplify the calculation process, and be easily implemented.

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