Research on the Stability of a System Consisting of a Water Hydraulic Control Valve and Cylinder

2016 ◽  
Author(s):  
Futoshi Yoshida ◽  
Shimpei Miyakawa ◽  
Shouichiro Iio
Keyword(s):  
Natural Frequencies ◽  
Tap Water ◽  
Control Valve ◽  
Working Fluid ◽  
Entire System ◽  
Hydraulic Control ◽  
Compensation Circuit ◽  
Design Guideline ◽  
Water Hydraulic ◽  
The Stability

Water hydraulic system using tap water as working fluid is a new driving method which provides high speed, high-output control, while providing safety, hygiene, and ecofriendliness. Its applicable markets widely range from food, health, pharmaceuticals, cosmetics, semiconductors, beverages, to energy industries. Applications of the water hydraulic technology differ from those of its oil counterpart in heavy industries. This paper is aimed at analytically considering the stability of systems that use tap water as the working fluid. We studied a comprehensive system, including a water hydraulic control valve, a cylinder, and piping for connecting these components, to determine the transfer function of the entire system that has three elements: a control valve; piping and cylinder; and a compensation circuit. Based on the determined function, we reviewed the relationship among natural frequencies of the system, including the control valve and piping, and examined the effect of the control valve and cylinder on the stability of the entire system according to the Hurwitz stability criterion. This gave us a design guideline about the compensation circuit that stabilizes the system by adjusting the natural frequency of the water hydraulic proportional control valve according to the natural frequencies of the piping and cylinder.

Design and Simulation on Multi-Digit Numerical Control Valve in Water Hydraulics

2011 ◽  
Vol 422 ◽  
pp. 257-261
Author(s):  
Zeng Meng Zhang ◽  
Yong Jun Gong
Keyword(s):  
Control Valve ◽  
Poor Performance ◽  
Numerical Control ◽  
Hydraulic Control ◽  
Control Performance ◽  
Poppet Valve ◽  
Water Hydraulics ◽  
Water Hydraulic ◽  
The Stability ◽  
And Control

Due to the problems about Lubrication and sealing in water hydraulics, the poor performance, large leakage, extreme requirements of processing, high cost and poor anti-pollution properties exist in water hydraulic servo or proportional valves of spool structure and analogue control. A better seal is provided by the structure of the poppet valve comparing to the spool valve, however, poorer linearity and control accuracy accompanying inevitably. Aiming at improving the control performance of poppet valve, the design of the multi-digit numerical control valve is analyzed in this paper. The novel design using ball seat valves for digital bits is proposed to ensure enough seal ability and lower the cost. The simulation model of the multi-digit numerical control valve is built in AMESim software and the results show high linearity in flow control. However, large overshoot and oscillation encounter during the switching of the digits. Especially the switching process of the high digital bits requires to be regulated to reduce the large overshooting. The adjustment of the spring in the sensitive chamber of the bit valve can decrease the overshoot and improve the stability. These above contribute to the improvement of the control performance of water hydraulic control valves and applications of water hydraulics in the industry.

Analysis and Simulation on Drive Characteristic of High-Strength Water Hydraulic Artificial Muscle

2014 ◽  
Vol 889-890 ◽  
pp. 488-492
Author(s):  
Zeng Meng Zhang ◽  
Jiao Yi Hou ◽  
Zheng Wen Sun ◽  
Yong Jun Gong ◽  
Jian Miao
Keyword(s):  
Flow Rate ◽  
Control Valve ◽  
Artificial Muscle ◽  
High Strength ◽  
Hydraulic Control ◽  
Hydraulic Circuit ◽  
Water Hydraulic ◽  
The Difference ◽  
Hydraulic Valves ◽  
Load Mass

Driving processes and characteristics are different between the water hydraulic artificial muscle and pneumatic artificial muscle due to the difference of work media employed in muscles. An appropriative hydraulic circuit was designed to control the pressure of the water hydraulic artificial muscle and the performance of this system was analyzed. An AMESim model of the control system was built and the dynamic characteristics are analyzed with various parameters of the hydraulic circuit and various loads by simulation. The results show that the performance of the water hydraulic control valve should agree with the dimension of the water hydraulic artificial muscle. The rated flow rate of the water hydraulic valves can be selected increasingly while the load mass is low. Meanwhile, the overshoot is generated and enlarged along with the increases of the flow rate and load mass. These contribute to the improvements of designs and researches on control systems of water hydraulic artificial muscles.

A Miniature On/Off Valve Concept for High Performance Water Hydraulics

2017 ◽  
Author(s):  
Miika Paloniitty ◽  
Matti Linjama
Keyword(s):  
High Performance ◽  
Control Valve ◽  
Hydraulic Control ◽  
Used Oil ◽  
Water Hydraulics ◽  
Starting Point ◽  
Pressure Medium ◽  
Water Hydraulic ◽  
Valve Control ◽  
Hydraulic Valve

Digital hydraulic control valve technology has shown its strengths in providing reliable, leak-tight and high performance valve control regardless of the pressure medium used, oil or water. This is enabled by the intelligent use of robust on/off seat valves. However, the availability of these valves for water hydraulics is limited, especially that of compact valves, which are needed for digital valve systems. Thus, with the aim to create a compact digital water hydraulic valve system, this paper presents the development process of a water hydraulic miniature valve. The starting point for the development is a previously developed miniature valve for oil hydraulics. Experimental results with the new prototype show that good performance can be achieved for the miniature valve even with using stainless steel materials. This enables high-performance digital water hydraulic control.

Modeling Spool-Valve Flow Forces

2004 ◽  
Author(s):  
Noah D. Manring
Keyword(s):  
High Speed ◽  
Transient Flow ◽  
Control Valve ◽  
Hydraulic Control ◽  
Pressure Transient ◽  
Pressure Transients ◽  
Accepted Practice ◽  
The Stability ◽  
Spool Valve ◽  
Insight Into

This paper has been written to reconsider the important topic of transient flow forces that act on spool-type hydraulic control valves. Though this subject has been addressed and somewhat laid to rest many years ago, the high-speed applications of our present day require a fresh look at this topic for gaining deeper insight into the significant contributions that determine the stability and frequency response of the hydraulic control valve. Over thirty years ago, it became an accepted practice to neglect the pressure transient flow-forces acting on the spool valve as they were deemed to be minor compared to the velocity effects of the spool itself. In this paper, flow force models with and without the pressure transient term are compared and it is shown that the historic practice of neglecting pressure transients may no longer be valid. As a result, this paper provides justification for considering the pressure transients in the analysis and may provide an explanation for some of the discrepancies that have existed between theoretical expectations and laboratory results.

Application of ultra-high molecular weight polyethylene in a hydraulic drive

2020 ◽  
pp. 77-78
Keyword(s):  
Molecular Weight ◽  
Low Temperature ◽  
High Molecular Weight ◽  
Hydraulic Drive ◽  
Control Valve ◽  
Hydraulic Control ◽  
Hydraulic Motor ◽  
Hydraulic Pump ◽  
Hydraulic Oil ◽  
Ultra High Molecular Weight

The use of ultra-high molecular weight polyethylene (UHMW PE) for the manufacture of various parts, in particular cuffs for hydraulic drives, is proposed. The properties and advantages of UHMW PE in comparison with other polyethylene materials are considered. Keywords ultra-high molecular weight polyethylene, hydraulic pump, hydraulic motor, hydraulic control valve, hydraulic oil, low temperature. [email protected]

scholarly journals DEVELOPMENT OF WATER HYDRAULIC PROPORTIONAL CONTROL VALVE

1999 ◽  
Vol 1999 (4) ◽  
pp. 549-554 ◽  
Author(s):  
Tamami TAKAHASHI ◽  
Chishiro YAMASHINA ◽  
Simpei MIYAKAWA
Keyword(s):  
Control Valve ◽  
Proportional Control ◽  
Water Hydraulic

scholarly journals Experimental Investigation on Stability, Viscosity, and Electrical Conductivity of Water-Based Hybrid Nanofluid of MWCNT-Fe2O3

Nanomaterials ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 136
Author(s):  
Solomon O. Giwa ◽  
Mohsen Sharifpur ◽  
Mohammad H. Ahmadi ◽  
S. M. Sohel Murshed ◽  
Josua P. Meyer
Keyword(s):  
Electrical Conductivity ◽  
Visual Inspection ◽  
Volume Concentration ◽  
Working Fluid ◽  
Hybrid Nanofluid ◽  
Multiwalled Carbon ◽  
Transmission Electron ◽  
Hybrid Nanofluids ◽  
Uv Visible ◽  
The Stability

The superiority of nanofluid over conventional working fluid has been well researched and proven. Newest on the horizon is the hybrid nanofluid currently being examined due to its improved thermal properties. This paper examined the viscosity and electrical conductivity of deionized water (DIW)-based multiwalled carbon nanotube (MWCNT)-Fe2O3 (20:80) nanofluids at temperatures and volume concentrations ranging from 15 °C to 55 °C and 0.1–1.5%, respectively. The morphology of the suspended hybrid nanofluids was characterized using a transmission electron microscope, and the stability was monitored using visual inspection, UV–visible, and viscosity-checking techniques. With the aid of a viscometer and electrical conductivity meter, the viscosity and electrical conductivity of the hybrid nanofluids were determined, respectively. The MWCNT-Fe2O3/DIW nanofluids were found to be stable and well suspended. Both the electrical conductivity and viscosity of the hybrid nanofluids were augmented with respect to increasing volume concentration. In contrast, the temperature rise was noticed to diminish the viscosity of the nanofluids, but it enhanced electrical conductivity. Maximum increments of 35.7% and 1676.4% were obtained for the viscosity and electrical conductivity of the hybrid nanofluids, respectively, when compared with the base fluid. The obtained results were observed to agree with previous studies in the literature. After fitting the obtained experimental data, high accuracy was achieved with the formulated correlations for estimating the electrical conductivity and viscosity. The examined hybrid nanofluid was noticed to possess a lesser viscosity in comparison with the mono-particle nanofluid of Fe2O3/water, which was good for engineering applications as the pumping power would be reduced.

PNEUMATIC VIBROISOLATION SYSTEM OF THE BASE DESK WITH NATURAL FREQUENCY REGULATION

2021 ◽  
Vol 113 ◽  
pp. 91-100
Author(s):  
Radka JÍROVÁ ◽  
Lubomír PEŠÍK
Keyword(s):  
Natural Frequency ◽  
Automotive Industry ◽  
Natural Frequencies ◽  
Dynamical Behaviour ◽  
Operating Conditions ◽  
Frequency Regulation ◽  
The Stability ◽  
Short Time

Vibroisolation systems of base desks for machine and testing facilities usually cannot effect efficient changing of their own frequencies according to operating conditions. Especially in the case of the automotive industry, the possibility of changing natural frequencies is very desirable. During varying operating conditions, the vibroisolation system needs to be regulated easily and quickly regarding the minimisation of dynamical forces transmitted to the ground and to ensure the stability of the testing process. This paper describes one of the options of tuning the base desk at a relatively short time and by sufficient change of own frequencies, which decides the dynamical behaviour of the whole system.

Vibration Modeling of Machine Tool Spindles: A Calibrated Dynamic Stiffness Matrix Method

2013 ◽  
Vol 651 ◽  
pp. 710-716 ◽  
Author(s):  
Omar Gaber ◽  
Seyed M. Hashemi
Keyword(s):  
Stiffness Matrix ◽  
Natural Frequencies ◽  
Dynamic Stiffness ◽  
Dynamic Stiffness Matrix ◽  
Spring Element ◽  
Linear Spring ◽  
Beam Bending ◽  
The Stability ◽  
Spinning Speed ◽  
Vibration Modeling

The effects of spindles vibrational behavior on the stability lobes and the Chatter behavior of machine tools have been established. The service life has been observed to reducethe system natural frequencies. An analytical model of a multi-segment spinning spindle, based on the Dynamic Stiffness Matrix (DSM) formulation, exact within the limits of the Euler-Bernoulli beam bending theory, is developed. The system exhibits coupled Bending-Bending (B-B) vibration and its natural frequencies are found to decrease with increasing spinning speed. The bearings were included in the model usingboth rigid, simply supported, frictionless pins and flexible linear spring elements. The linear spring element stiffness is then calibrated so that the fundamental frequency of the system matches the nominal value.

Sign in / Sign up

Export Citation Format

Share Document