Vibration Separation Methodology Compensated by Time-Varying Transfer Function for Fault Diagnosis of Non-Hunting Tooth Planetary Gearbox

Due to planetary movement of planet gears, the vibration signal perceived by a stationary sensor is modulated and difficult to diagnose. This paper proposed a vibration separation methodology compensated by a time-varying transfer function (TVTF-VS), which is a further development of the vibration separation (VS) method in the diagnosis of non-hunting tooth planetary gearboxes. On the basis of VS, multi-teeth VS is proposed to extract and synthesize the meshing signal of a planet gear using a single transducer. Considering the movement regularity of a planetary gearbox, the time-varying transfer function (TVTF) is represented by a generalized expression. The TVTF is constructed using a segment of healthy signal and an evaluation indicator is established to optimize the parameters of the TVTF. The constructed TVTF is applied to overcome the amplitude modulation effect and highlight fault characteristics. After that, experiments with baseline, pitting, and compound localized faults planet gears were conducted on a non-hunting tooth planetary gearbox test rig, respectively. The results demonstrate that incipient failure on a planet gear can be detected effectively, and relative location of the local faults can be determined accurately.

Validation of a coupled multibody and TEHL simulation by a piston/cylinder component test rig

A tribological highly stressed contact in the actuating system of axial piston machines is located between the control piston and the control chamber. This paper presents a new type of component test rig for measuring the frictional force and the gap heights between piston and cylinder. For this purpose, the original system is reduced to the actuator system, whereby the real kinematics and the loading forces are maintained. The axial movement of the control piston and the pressure in the control chamber can be configured individually. The measurement results of different parameter variations are compared with the results of the simulation. The simulation based on a coupled multibody and TEHL simulation with a transient, three-dimensional, thermal elastohydrodynamic contact calculation.

Design of an Innovative Test Rig for Industrial Bearing Monitoring with Self-Balancing Layout

The remote prognosis and diagnosis of bearings can prevent industrial system failures, but the availability of realistic experimental data, being as close as possible to those detected in industrial applications, is essential to validate the monitoring algorithms. In this paper, an innovative bearing test rig architecture is presented, based on the novel concept of “self-contained box”. The monitoring activity is applicable to a set of four middle-sized bearings simultaneously, while undergoing the independent application of radial and axial loads in order to simulate the behavior of the real industrial machinery. The impact of actions on the platform and supports is mitigated by the so-called “self-contained box” layout, leading to self-balancing of actions within the rotor system. Moreover, the high modularity of this innovative layout allows installing various sized bearings, just changing mechanical adapters. This leads to a reduction of cost as well as of system down-time required to change bearings. The test rig is equipped with suitable instrumentation to develop effective procedures and tools for in- and out-monitoring of the system. An initial characterization of the healthy system is presented.

Experimental Test Setup for Deoiling Hydrocyclones Using Conventional Pressure Drop Ratio Control

Summary Produced water is a major challenge in the oil and gas industry, especially with the aging of oil fields. Proper treatment of produced water is important in reducing the environmental footprint of oil and gas production. On offshore platforms, hydrocyclones are commonly used for produced-water treatment. However, maintaining the efficiency of hydrocyclones subjected to plant disturbances is a difficult task owing to their compact nature. This paper describes a new experimental test rig built at the Department of Mechanical and Industrial Engineering at the Norwegian University of Science and Technology for testing industrial-scale hydrocyclones. The test setup can emulate first-stage separation and create plant disturbances, such as changes in flow rate, oil concentration, and oil droplet distribution at the inlet of the hydrocyclones. Also, the setup is capable of testing different control algorithms, which helps to maintain the efficiency of hydrocyclones in the presence of such disturbances. The test rig is equipped with various instruments that can monitor such parameters as pressure, flow, temperature, and oil concentration. A typical pressure drop ratio (PDR) control scheme for hydrocyclones is tested in the test rig, which can control the disturbances in the inflow rate. The PDR control scheme does not detect disturbances in the inlet oil concentration and changes in droplet distribution, and these scenarios are shown experimentally in this paper.

A COMPACT AND PORTABLE DESIGN DEVELOPMENT OF A LOW ROLLING RESISTANCE TEST RIG

Low Rolling Resistance (LRR) conveyor systems are generally preferred over traditional conveyors because of better overall efficiency lesser energy consumption required to operate. In this work, the design development and analysis path in the process of downscaling the size of an existent LRR test rig to a compact, portable and desktop-sized model is presented. Simulation has been developed using SolidWorks and finite element analysis is conducted using ANSYS to obtain the deformation, stress and strain of each part of the new design.

An Experimental Study into the Behaviour of Tube and Fitting Scaffold Structures under Cyclic Side and Vertical Loads

The United Kingdom and European codes for the analysis and design of tubular scaffold structures assume that the scaffolds are subjected primarily to vertical loads and to horizontal loads at right-angles to the scaffold. The effects of dynamic loading caused by large winds tend to be ignored and the code analyses often only require static loading on the structures to be considered. To investigate side loads, a scaffold frame built according to the UK standard was made and inserted into a testing rig. Five different load combinations were made to determine the behaviour of the scaffold under different side loads, which were varied cyclically to simulate different wind loads, especially when vertical loads were also applied. The results showed that cyclical loads affected scaffold behaviour, especially when the bases of the scaffold standards were not tied to the base at the bottom of the test rig. Changes should be made to the UK and European codes BS EN 74.1, BS 5975 and BS EN 128 11-1 for the design of scaffold structures to increase safety.

Development and Evaluation of Low-Damage Maize Snapping Mechanism Based on Deformation Energy Conversion

Reducing ear damage is the key to improving the quality of maize harvests. In order to reduce the impact and damage of the ear caused by the ear snapping mechanism, this paper proposes a method to convert ear deformation energy during collision into elastic potential energy in the ear snapping mechanism. According to the above method, a low-damage maize snapping mechanism was designed. In order to verify the feasibility of energy conversion in reducing damage, the dynamic model of the contact between the ear and the snapping plate was established, and a dynamic simulation analysis was carried out based on the finite element method (FEM). In order to obtain better parameters for the improved mechanism, a test rig was established, after which a performance test was carried out on the test rig. The results showed that the primary and secondary order that affected the ear damage rate was the rotational speed of the snapping roller, the spring stiffness and the forward speed. The data processing software Design Expert was used to optimize the parameters, it was concluded that when the rotational speed was 805 r·min−1, the forward speed was 1.29 m·s−1, the spring stiffness was 33.5 N·mm−1, the model predicted that the ear damage rate was 0.023%. Therefore, this paper could provide further reference for research into maize low-damage ear snapping technology.

Iron Oxide and Water Paste Rheology and Its Effect on Low Adhesion in the Wheel/Rail Interface

The “wet-rail” phenomenon results in low adhesion between wheel and rail throughout the year, occurring transiently on a slightly wet, or drying railhead. It has been previously proposed that it is caused by a mixture of iron oxides and small amounts of water (from dew or precipitation) on the railhead that form a friction reducing paste. This paper outlines a novel combination of rheology, modelling and experimental work using a twin disc test rig to determine how the rheology of this iron oxide paste affects adhesion. The yield strength of different types of iron oxides, along with solid oxide fraction of the friction reducing paste, was assessed and used as an input into an “adhesion model” for assessing water and oxide suspensions. The rheological and modelling results were compared against very low adhesion recorded in twin disc experimental validation when simulating the wet-rail phenomenon.