Valve Plunger Research Articles

A New Physics-Informed Condition Indicator for Cost-Effective Direct Current Solenoid Valves Using Significant Points of the Excitation Current

Abstract This paper proposes a new condition indicator (CI) for cost-effective industrial direct current (DC)-powered solenoid valves (SVs). First, a literature review of the failure modes for SVs is reported. The failure regarding the impeded movement of the valve plunger is considered. The proposed CI for this failure mode is computed from only some significant points of the SVs excitation current and their time instants. The proposed CI is evaluated by a large endurance campaign on a set of SVs. Then, a Remaining Useful Life (RUL) estimation algorithm is proposed and evaluated on the experimental data. Experimental results show the goodness of the proposed CI for RUL estimation of cost-effective industrial DC SVs.

Modeling and Validation of Moving Coil Actuated Valve for Digital Displacement Machines

This paper concerns a novel moving coil actuator integrated with a high-performance seat valve for use in digital displacement machines (DDM), which is an emerging fluid power technology that sets strict actuator requirements in order to get a high energy conversion efficiency. Hence, the mechanical switching time must be in the millisecond range and the actuator power consumption must be in range of few tens of watts. The objectives are twofold: First, establish a proof-of-concept for the integrated actuator/valve that relies on several principles and mechanisms new or uncommon in fluid power applications. Second, formulate and validate a transient numerical model describing the actuator/valve. A coupled simulation model is established to predict the switching performance in which transient electromagnetic finite-element-analysis with dynamic remeshing is coupled to a set of ordinary differential equations describing the motion dynamics. In this way, the movement induced hydromechanical fluid forces caused by rapid acceleration of the valve plunger is coupled with the electromagnetic dynamics. The proposed model is compared rigorously against measurements obtained from a series of experiments based on a fully operational valve prototype. Comparisons of, e.g., transient flux density, current, and plunger position, show that the model describes both the actuator and the valve motion very well. Finally, results are presented when testing the prototype valve in fully operational DDM to establish proof-of-concept for the proposed valve concept. The actuator/valve is shown to be capable of rapid switching in less than 4 ms, while only consuming approximately 45 W corresponding to 0.7% of the machine output power.

Optimal Design of Engine Variable Stretching for Valve Stem of 157FMI

When designing motorcycle engine, engine cylinder head abnormal noise is common, and difficult to eliminate due to thermal expansion and contraction of the aluminum alloy cylinder head. In this study, on the basis of dynamic change with the performance of 157FMI engine in hot and cold, the reasons for engine cylinder head abnormal noise are analysed, and valve plunger with variable length is applied to minimize the valve clearance, and to make the valve clearance of engine in cold and hot zero, and thus the noise problem of cylinder head with 157FMI engine in hot is completely eliminated.

A simple method for automotive switching-type solenoid valve stuck fault detection

This paper proposes a method for the diagnosis of faults in switching-type solenoid valves widely used in automotives, specifically the case in which the valve plunger is sticking during operations. This kind of fault is frequently encountered in electro-hydraulic systems of in-use vehicles and is difficult to detect because the solenoid valves are generally inside the system. A Kalman filter-based fault detection algorithm is derived. Experimental results showed that, using only the measured voltage across and current through the coil of the solenoid, the designed algorithm predicted the plunger motion and diagnosed the stuck fault accurately.

Pressure control scheme for air brakes in commercial vehicles

Air brake systems are widely used in commercial vehicles such as trucks, tractor-trailers and buses. In these brake systems, compressed air is used as the energy transmitting medium to actuate the foundation brakes mounted on the axles. Here, we present a control scheme for regulating the pressure of air in a brake chamber of these brake systems. This scheme is based on a non-linear model for predicting the pressure transients in the brake chamber that correlates the brake chamber pressure to the treadle valve (brake application valve) plunger displacement and the pressure of the air supplied to the brake system. The control scheme regulates the pressure in the brake chamber by modulating the displacement of the treadle valve plunger. We have implemented this control scheme on the brake testing facility at Texas A&M University and present results for a variety of test runs in which the controller tracks realistic desired pressure trajectories.

Finite element analysis of flow in a hydraulic pressure valve

The paper describes a finite element study of laminar flow of oil through a hydraulic pressure-relief valve of the differential-angle type used in a variable compression ratio piston of an internal combustion engine. The model simulates an experimental setup used to obtain the performance characteristics of the valve under steady-state conditions. The velocity and pressure distributions through the valve and the magnitude of the lift forces on the plunger are obtained under a constant inlet pressure condition for various plunger lifts. Comparisons are made with the available experimental and analytical data. The details of the flow through the valve are predicted with a good degree of accuracy. The results provided an improved understanding of the way in which opening forces on the valve plunger are generated at various plunger lifts and are thus helpful to the design process. The complex flow fields generated resulted in the formation of recirculation zones and modified the minimum flow areas, thus affecting the pressure distribution and the force on the plunger.