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The units of electric conductivity are defined and the problems associated with conventional instruments are mentioned. The principle of operation of the electrodeless conductivity meter is explained along with manufacturing details. Applications to process control are mentioned and barriers to wider acceptance are discussed.

Nano graphite (50-60nm) displays excellent lubricating property and agglomerates easily into big particles in acidic electrolyte, which lead to its lower content in composite coatings. The influence of nano carbon particles concentration in bath, current density, temperature and agitating method on the properties of electrodeposited black Cr-C composite coating and wearing resistance of Cr-C coating were studied in this paper. The surface morphology and phase structure of the coatings were analyzed by means of scanning electronic microscopy (SEM) and X-ray diffractometer (XRD), and its microhardness was determined by micrometer. The results showed that the maximum microhardness of black Cr-C nano-composite coating was 10.8 Gpa, the maximum vol.% in coating was 8.82, which formed under current density of 100A/dm2, temperature of 15°C, ultrasonic wave plus slow mechanical agitation. The optimum particle content in electrolyte was 10g/l.

The type of surface that is used in the cylinder bore of a small aluminum engine is a critical item. This paper describes all the techniques presently used: the iron liner, the chrome plated cylinder, the nickel-silicon carbide composities, the Reynolds 390 aluminum alloy, and aluminum cylinders with chrome plated pistons. The emphasis is on the electrodeposits used in cylinder bores.

Outboard motors use aluminum die-cast components extensively to cut down their weight. They are also cooled directly by the raw water including saline water. Corrosion protection is the critical issue for outboard motors because of these characteristics. Currently, the coating is the primary measures taken to assure the corrosion resistance and to give originality to the appearance. However, the complicated cooling passages cannot be coated appropriately with the spray-paint process. Such disadvantages can be compensated by the electrodeposition coating technique. In the case of electrodeposition coating, the coating film is generated electrically in the coating material bath by means of deposition. The process is widely applied to the automobile bodies made of steel plate, because it provides higher transfer efficiency and lower VOC (VOLATILE ORGANIC COMPOUNDS) emission.

Electrodialysis is used to remove salts from waste or other water streams, to yield a concentrated brine and a substantially deionized product water. During the electrodialysis process, the boundary layer adjacent to the ion selective membrane can become depleted of ions, resulting in severe pH changes sometimes accompanied by precipitation, and power losses, by a process known as “water-splitting.” In order to optimize the applied electric current density, to achieve maximum deionization without exceeding the limiting current at any point along the path, a simulation program has been created to plot ion concentrations and fluxes, and cell current densities and voltages, along the electrodialysis path. A means for tapering the current density along the path is recommended.

Electroemissive (ESTHER) devices are thin sheets - similar to solar cells - whose infrared emissivity can be varied reversibly by electrical charging. Bonded to the external surfaces of spacecraft radiators they can be used for the active control of the Irradiated heat by consuming negligible electrical energy. The window to a revolutionary new thermal control design technology for spacecraft may be opened.

A new orifice plate (OP) for advanced fuel injection characteristics is presented. The OP is designed to optimize the air-fuel mixture generation and transportation within individually shaped manifold geometries of spark-ignition engines. To generate the suitable spray characteristics, the basic OP design and its flow characteristics have some features originating from the well known turbulence nozzle principle: Turbulence generating flow deflections within the OP are achieved by superimposing layers containing flow cavities, which are displaced from one another. The flow deflections effect atomization and define the spatial spray beam orientation. A great variety and a high volume of precisely structured, low cost OPs can be produced daily by micromachining the layers in electroformed nickel. The flow cavities and outer dimensions of each layer are shaped by photo-resist structures.

Electrofuels produced from renewable hydrogen (H2) and captured carbon dioxide (CO2) can be sustainable and carbon-neutral. Paraffinic electrodiesel (e-diesel) can be produced via Fischer-Tropsch synthesis with fuel properties resembling hydrotreated vegetable oils. Electrofuels can be also oxygenated compounds, such as oxymethylene dimethyl ethers (OMEn), having different chain lengths. We studied emissions using paraffinic diesel mimicking e-diesel and its blend with 10% of OME3-5, which has diesel-type fuel properties, in comparison with normal EN590 diesel fuel. An intensive measurement campaign was performed with a modern diesel engine without exhaust aftertreatment to study the effect of fuel on the engine-out emissions. Measurements with the RMC-C1 cycle included detailed characterization of gaseous, particle and polyaromatic hydrocarbon (PAH) emissions having adverse effects on health and the environment.

The benefits of bake-hardening steels for body applications in the automotive industry are well known since several years. These steels offer the potential of weigth savings without major loss of formability. Thus this group of high-strength steels is the first to find broad application for exposed panels. This paper sums up the different concepts of producing cold-rolled electrogalvanized and hot-dip galvanized bake-hardening steels. These concepts are critically discussed from the point of view of stable production. Important aspects for batch annealed or continuously annealed steels are the control of grain size and temper rolling. New hot-dip galvanized bake-hardening steels have been developed; as a result of degassing to ultra low carbon contents in modern vacuum treatment facilities. Beside bake-hardening effects special emphasis is given to the strain-hardening behaviour and to the ageing resistance of bake-hardening steels.

The corrosion performance of 17 hot dip and electrolytic zinc and zinc alloy coated steel samples exposed for five consecutive winters in undervehicle tests is reported in this paper. The program initiated by Dofasco in 1981, used two commercial trucks operating in the deicing salt/snow belt region of Southern Ontario, Canada. Results of the phosphated and cathodic primed coupons confirmed our previous observations on unpainted coupons that the hot dip coated steels with the thicker coatings outperformed the electrolytic coated steels. A new test program Has started in 1984. This program uses paired “t” test statistics to compare the undervehicle corrosion performance of hot dip and electrogalvanized coupons of similar coating mass. Results after one and two winters will be presented.

As new smart systems for passenger cars are assisting me driver to handle manoeuvres in critical and normal situations, brake systems are required to fulfill the compatibility and interface demands. These advanced brake systems will be operated in a remote mode during normal braking and for autonomous brake interventions. BOSCH is developping a brake-by-wire system on a hydraulic basis, called ‘Electrohydraulic Brake EHB’. Brake pressure buildup is supplied by a high pressure accumulator. Generation of the high pressure is done by an electric motor driven pump, similar to current ABS-systems. Pressure at the wheel brakes is individually controlled by closed-loop pressure control, consisting out of inlet, and outlet valves, pressure sensor and corresponding algorithm. It is specified, that this control must be completely noiseless, proportional, fast, and highly accurate. To raise the acceptance of such a system, it will be introduced with a conventional hydraulic backup.

Because of the unique control characteristics of electrohydraulic proportional valves-smooth acceleration and deceleration, and the ability to inch or feather the work platform into position-several methods have been devised to use electrohydraulic valves to control electrically insulated aerial lifts. Since all components bridging the insulated portions of the boom structure must have an insulating value equivalent to the boom itself, it is not permissible to run electrical control cables from the work platform down the insulated boom to the control valves mounted on the chassis below. Systems using radio signals and light signals (via fiber optic bundles) are being developed to control the more complex, multifunctional aerial lift boom structures.

Hydrostatic Transmissions have gained widespread acceptance on mobile equipment over the last decade. They offer an efficient means to transmit energy at high power levels, while maintaining smooth proportional control. In the last few years, electrohydraulic devices have become available for stroking pump and motor swashplates with small electrical signals. This capability creates almost unlimited possibilities for improved control of mobile vehicles, ranging from simple remote control of the pump swashplate to sophisticated automatic control. This paper discusses the more practical types, including steering, crossover control (pump/motor phasing), engine anti-stall control, pressure override, and constant-speed control.

Earlier transmissions were equipped with a complex mechanical linkage for actuating the dual power planetary gear set. Field experience revealed the need for a reliable, simplified and less expensive method for this particular transmission control. An electrohydraulic directional control valve was developed to provide an economical design improvement which was readily incorporated into present models.

High pressure, load sensing valves, like the Vickers actuator mounted CMX valves, demonstrate significant advancement in performance and efficiency with the adaptation of electrohydraulic pilot controls. Electrohydraulic feature provides increased operator comfort, simplified plumbing, improved control properties and adaption to microprocessor electronics on mobile systems.

Valve-controlled hydraulic drives are frequently used when high dynamics, high reliability and a compact structural form are required. A disadvantage which is frequently attributed to a valve-controlled drive is its poor running efficiency. It not only leads to higher energy consumption but - amongst other things - to the necessity of installing larger pumps and more elaborate cooling equipment. Both these factors cause an increase in the costs of hydraulic drives. Load sensing is known from the field of mobile hydraulics as a driving concept with high running efficiency. In load sensing the supply pressure is adjusted to suit the actuator's highest point of load pressure. The dynamics of this system is worse than that of systems with a constant supply pressure. Electrohydraulic load sensing offers possibilities to improve the dynamics of valve-controlled drives in load sensing by using control engineering measures.

The electrohydraulic power steering (EHPS) system is a new approach to the supply of power steering to vehicles requiring supplementary assist. It may be used in vehicles where a standard engine-driven pump system cannot be packaged. An additional benefit is the ability of the system to shift to manual operation as a function of road speed. Such a shift to manual operation could be based on input signals from the driver as well. The unit as presently designed is most efficiently used in a vehicle with a front end weight of less than 600 KG (1320 lbs.). However, if upsizing of the system should be required, the overall package has been designed with this option in mind. The electrohydraulic power steering system is designed in a modular format. The pump package consists of an electronic controller, motor, pump, and reservoir, attached to a main bracket. A unique hydraulic fluid is utilized to allow adequate performance over a wide temperature range.

The results from an investigation of some of the effects of using a linearized model for prediction of the behavior of a nonlinear system are presented. The system studied is a velocity system using an electrohydraulic servoactuator to drive an inertial load. Both nonlinear and linearized system models are defined. The result of defining optimal feedback values for an integral quadratic performance index is shown along with the effect of choice of nominal operating point on the linearized system transient response. Finally, linear and nonlinear transient responses are compared for a range of step amplitudes.

An accurate nonlinear model of a typical magnetic actuator is included in a new SPICE simulation of an electrohydraulic system. The actuator model is obtained by electromagnetic finite element analysis. The resulting nonlinear magnetic flux linkages and forces as functions of airgaps and currents are included in the SPICE model. The SPICE model is able to include electronic driver circuits and models of the hydraulic circuits, which are shown to interact to determine the closing time of electrohydraulic valves.