Paper 6: Hydraulic Control of Valves in Tankers

The 47 800-ton vessel Altair of the Compagnie Navale des Pétroles (C.N.P.) was the first oil-tanker to be equipped with a hydraulic remote-control system of cargo valves. The vessel was delivered at the beginning of May 1959. The opening and closing operations of the valves were controlled from a central panel which was fitted with manually operated directional control valves. The panel was located in the cargo valves' remote-control room which also housed the indispensable remote-controlled level-indicator board. Since then the application of hydraulic remote-controlled valves has become widespread and has taken one of two forms : that of a centralized control system or that of directional control valves located on the deck. Remote-controlled valves are either gate valves operated by a hydraulic cylinder, or butterfly valves operated by a hydraulic rotary actuator. The application of remote-control also allowed the setting up of the ‘free-flow’ system which uses hydraulically operated bulkhead valves. The first ‘free-flow’ oil-tanker was the Sirius of the C.N.P.; it was delivered in 1961. At present it appears that there exists an ever-increasing trend towards automation in the loading and unloading of tanker cargoes. This is accomplished by electrically operated directional control valves, which are connected with electrically programmed systems or with electronic servo-controls.

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Design of Transverse Boom-Type Roadheader Remote Control System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.701-702.679 ◽

2014 ◽

Vol 701-702 ◽

pp. 679-683 ◽

Cited By ~ 2

Author(s):

Xiao Dong Wang ◽

Ming Quan Shi ◽

Shu Jun Gao ◽

Yang Chen Guo

Keyword(s):

Control System ◽

Remote Control ◽

Hydraulic Cylinder ◽

Personal Injury ◽

Programmable Logic ◽

Mining Operations ◽

Remote Control System ◽

Cutting Head ◽

Main Production ◽

Geometric Relationship

The roadheader remote control system is proposed to protect operator away from the dust and the danger on working site, improve the operator's labor environment, reduce personal injury accidents, and enhance the security of mining operations. The cutting head and spade board position of transverse boom-type roadheader were analyzed. The mathematical models of cutting head vertical swing, cutting head gyration swing and spade board vertical swing were established. Geometric relationship between the angle and the stroke of hydraulic cylinder of cutting head and spade board were calculated. Finally, based on programmable logic controller (PLC) and industrial personal computer (IPC), the remote control system was designed and the automatic cutting method was proposed. The roadheader remote control system had been applied successfully in EBH132 roadheader. The system significantly enhances the efficiency and security of the main production.

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Study Control System Based on Creep Test in High Density Baler

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.139-141.1624 ◽

2010 ◽

Vol 139-141 ◽

pp. 1624-1627

Author(s):

Wei Lee ◽

Chun Guang Wang

Keyword(s):

Control System ◽

Data Acquisition ◽

Creep Test ◽

Hydraulic System ◽

Electrical Contact ◽

Hydraulic Cylinder ◽

High Density ◽

Hydraulic Control ◽

Creep Tests ◽

Relief Valve

Hydraulic transmission system controls hydraulic cylinder forward and backward movement freely, in order to achieve high density hydraulic baler work circulation. Creep test required hydraulic system to output constant stress, and study creep tests can not be completed when used succeeding the electrical contact style in the past time. The system used programmable logic controller (PLC) to instead of succeeding the electrical contact style and realized freely forward and backward movement of hydraulic cylinder, electro-hydraulic proportional relief valve can adjust hydraulic system and make it stepless pressure regulation and then degree of automation and reliability in hydraulic control system to be improved. This paper introduces aspects: including the selection, hardware configuration and program of PLC, meanwhile, giving specific realization method. Through the control system to study creep test in hydraulic baler, adopting the National Instrument (NI) company's multi-channel data acquisition card, which type is USB-6251,applying Labview8.2 to write data acquisition program on my own, the versatility and flexibility of system was verified, which was able to complete creep test successfully.

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Selection of Operating Modes of a Multi-Functional Hydraulic Device

Fluid Power Systems and Technology ◽

10.1115/imece2005-81687 ◽

2005 ◽

Cited By ~ 1

Author(s):

Amir Shenouda ◽

Wayne J. Book

Keyword(s):

Control System ◽

Energy Saving ◽

Hydraulic System ◽

Force Feedback ◽

New Technology ◽

Hydraulic Cylinder ◽

Hydraulic Control ◽

Operating Modes ◽

Machine Productivity ◽

Spool Valve

The field of earth moving equipment is experiencing a transformation due to the introduction of more electronic control capability and advanced control concepts. Conventional hydraulic control systems are controlled by proportional directional spool valve. The construction of the spool valve is such that a given position of the spool determines the flow in and the flow out restriction sizes. Thus, metering in and metering out are dependent or coupled. A certain restriction size on the inlet corresponds to a certain restriction size on the outlet. Therefore, we have one degree of freedom. It can provide for good motion control but it cannot achieve energy saving potential at the same time. In this paper, the concept of ‘independent meter in / meter out’ will be emphasized. Decoupling of meter in from meter out provides for more controllability and potential for energy saving in overrunning load cases when compared with a conventional spool valve controlled hydraulic system. A four-valve configuration controlling a hydraulic cylinder will be stressed. The four-valve configuration can operate in several modes because each of the four valves is controlled separately from the others. Five of these metering modes will be pointed out; two conventional modes and three regenerative modes. An industry system supplier has introduced a novel distributed independent metering in/meter out hydraulic system with actuator force feedback. This control system is going to presented in brief. The distributed, actuator mounted implementation of this system maximizes the efficiency of the regeneration flow by minimizing the line losses associated with the recirculating fluid This control system can be used to control a multi-functional hydraulic device, e.g. excavators, tractor loader backhoes, etc... An experiment was done where a typical dig cycle was performed by a tractor loader backhoe equipped with this new technology. The data recorded from this experiment is used to perform an off-line optimization of metering modes selection for each function during the cycle. this off-line optimization can be used to maximize machine productivity or machine efficiency or a weighted combination of both. A general objective function will be presented and results will be given for maximizing machine productivity. Finally conclusions and future work suggestions are presented.

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Performance Analysis of Directional Control Valve: An Overview

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.592-594.1983 ◽

2014 ◽

Vol 592-594 ◽

pp. 1983-1987

Author(s):

Ramashankar Paswan ◽

Jayanta Das ◽

N. Kumar ◽

Ajit Kumar ◽

Santosh Kumar Mishra ◽

...

Keyword(s):

Control Valve ◽

Open Loop ◽

Compressed Air ◽

Hydraulic Control ◽

Control Valves ◽

Directional Control ◽

Full State ◽

Full State Feedback ◽

High Bandwidth ◽

Valve Control

Directional control valves start, stop or change the direction of flow in compressed air applications. To understand the different applications of compressed air and how valves are used, one must first have knowledge of the kinds and types of valves used by industries. This paper studies local valve control of the electro-hydraulic system. The slow response of hydraulic control valve usually becomes the hold-up of whole system performance. Although fast valves (e.g. high-bandwidth servo-valves) are available, they are far more expensive than slow valves (e.g. proportional directional control valves). To improve the performance of proportional directional control valves, three different types of controllers are synthesized. Firstly, based on the pole zero cancellation technique, an open loop compensator is designed which requires the accurate valve dynamic model information; Secondly, a full state feedback adaptive robust controller (ARC) is synthesized, which effectively takes into account the effect of parametric uncertainties and uncertain nonlinearities such as friction force and flow force. Finally, an output feedback ARC controller is synthesized to address the problem of un measurable states. Keywords: valve, hydraulic device, Simulink.

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Impact of Long Hydraulic Pipeline upon Performance of Hydraulic Control System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.328-330.2148 ◽

2011 ◽

Vol 328-330 ◽

pp. 2148-2151

Author(s):

Ya Nan Zhao ◽

Hong Wang Du ◽

Yu Mei Li ◽

Xiang Luo ◽

Gang Liu

Keyword(s):

Pressure Sensors ◽

Control Valve ◽

Hydraulic Cylinder ◽

Hydraulic Control ◽

Relief Valve ◽

Supply Pressure ◽

Directional Control ◽

Cylinder Piston ◽

The Impact ◽

Directional Control Valve

In ocean exploitation, long hydraulic pipelines are usually applied. Using SimHydraulic software, the model of hydraulic system including hydraulic fluid, pump, hydraulic cylinder, directional control valve, relief valve, accumulator, long supply pipeline and return pipeline, is established. The position of the cylinder piston is measured by position sensor, while the supply pressure of the cylinder and the system supply pressure are measured by pressure sensors, the directional control valve is controlled by an on-off signal. The simulation was carried out, the impact of long hydraulic pipeline on system performance is also analyzed.

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Performance Improvement of Proportional Directional Control Valves: Methods and Experiments

10.1115/imece2000-2315 ◽

2000 ◽

Author(s):

Fanping Bu ◽

Bin Yao

Keyword(s):

Control Valve ◽

Open Loop ◽

Parametric Uncertainties ◽

Hydraulic Control ◽

Tracking Accuracy ◽

Control Valves ◽

Output Tracking ◽

Directional Control ◽

Full State Feedback ◽

High Bandwidth

Abstract This paper studies local valve control of the electro-hydraulic system. The sluggish response of hydraulic control valve usually becomes the bottleneck of whole system performance. Although fast valves (e.g. high-bandwidth servo-valves) are available, they are far more expensive than slow valves (e.g. proportional directional control valves). To improve the performance of proportional directional control valves, three different types of controllers are synthesized. Firstly, based on the pole zero cancellation technique, an open loop compensator is designed which requires the accurate valve dynamic model information; Secondly, a full state feedback adaptive robust controller (ARC) is synthesized, which effectively takes into account the effect of parametric uncertainties and uncertain nonlinearities such as friction force and flow force. Finally, an output feedback ARC controller is synthesized to address the problem of unmeasurable states. Theoretically, the proposed ARC controllers guarantee a prescribed output tracking transient performance and final tracking accuracy while achieving asymptotic output tracking in the presence of parametric uncertainties. Comparative experimental results are obtained to show the advantages and limitations of each method.

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