Design Of Test Rig Research Articles

Wear behaviour of acetal gear pairs

The wear behaviour of polymer gear pairs has been little studied. Most wear studies have used pin-on-disc or polymer against steel tests. The non-conformal contact and high transient temperatures in polymer gear pairs make it essential to study wear under actual running conditions. This paper describes the design and operation of a novel test rig for measuring the wear behaviour of polymer gears continuously. Preliminary results are presented and comparisons made between failures in acetal and nylon. Wear of acetal gears is studied in more detail. It is shown that wear of acetal gears is a complex process. Optical and scanning electron microscopy (SEM) show the driving and driven gears to have different features on the worn flanks, with a ridge forming at the pitch line on the driven gear and a valley on the driving gear. The wear surfaces over the addendum and dedendum are also strikingly different. This is related to the direction of rolling and friction forces on each gear face. The limits to the use of acetal as a gear material are considered. At low torques, life is limited by wear and at high loads the maximum permissible surface temperature is a limiting factor.

Design of a slurry erosion test rig

The design of a jet impingement slurry erosion test rig, built for laboratory use, is presented. This apparatus gives good control over many of the important test parameters, such as impact velocity, solid particle concentration and impact angle. An ejector nozzle is employed to entrain sand particles from a sand bed into a stream of water to form a slurry; after impingement, the abrasive particles and the water phase are separated and recycled. This makes the rig simple, economical and easy to operate and its pump and pipeline remain free from erosive wear. Experimental results are presented to illustrate the operation and performance of the rig.

Testing of large diameter pile rock sockets with a retrievable test rig : Johnston, I W; Donald, I B; Bennet, A G Proc 3rd Australia-New Zealand Conference on Geomechanics, Wellington, 12–16 May 1980, V1, P105–108. Publ Wellington: New Zealand Institution of Engineers, 1980

This paper describes the design, construction and use of a retrievable test rig for evaluating the performance characteristics of large diameter pile rock sockets. The test rig is prefabricated at ground level, lowered into a contract socket, and concreted into position. Large flat jacks react against the base of the socket to force a concrete annulus, representing a section of the pile shaft, upwards eventually to failure. The side shear resistance characteristics to failure and the base resistance characteristics well in excess of design load may be determined. After testing, by use of special design features, the rig and concrete may be rapidly removed from the socket to allow the contract pile to be completed. The results of two such tests conducted in a contract socket of a major construction project in Melbourne are reported to demonstrate the effectiveness of the technique.

Traction measurements in the thermal region of the traction curve

Difficulties when measuring in the decreasing thermal region of the traction curve are described, and one stable test-rig design is presented. Experimental evidence for a theoretical prediction presented earlier by the author is also given

Design of a Dynamic Gear Test Rig

Abstract A test rig for plastic spur gears has been designed and built, based on the principle of an eddy current dynamometer. This offers considerable advantages over existing gear test rigs in that the torque level is infinitely variable and it can be adjusted if necessary during testing. A special noncontacting tooth breakage detector was also developed to stop the tests immediately if failure had occurred. An extension to the basic test procedure is also described whereby real life loading situations can be easily simulated with a minicomputer coupled to the dynamometer.

The flow characterisation of a high-gradient magnetic separator

A review is given of what is required from flow-pressure-drop tests on a multi-fibre high-field-gradient magnetic filter mesh and suggests methods of how the desired results may be obtained. The salient features of the problem are high-lighted so as to aid the production of meaningful data and its presentation to the filter designer in as general and useful a form as possible. Techniques and instrumentation suitable for experimentation in this type of flow problem are outlined and the advantages of air as a test medium are explained. The conditions for successful model testing and the relating of model results to full size filters are discussed (with special attention to the problem of the flexure of low-solidity filters) as are the design of a suitable test rig and the sizing of associated equipment.

Concorde Equipment

The Aviation Division of the Dunlop Co. Ltd. (Engineering Group) is to install Dynex power units, designed and built by Applied Power (U.K.) Ltd., in the latest design of hydraulic production test rigs at the Division's Coventry factory. The company is completely re‐equipping its production test facilities by providing every rig with the higher pressures and flows which future trends in fluid technology will demand, and to ensure that each testing station is capable of handling service fluids currently in use, including kerosene, DTD 585, Skydrol, Lockheed 22 and Oronite.

Report 23: Considerations in the Design of Plain Sliding Test Rigs

After outlining the relative merits of rig-testing of materials compared with testing in situ the fundamental considerations in the design of the testing machine are discussed. Of basic importance is a realistic appraisal of the conditions under which the material is to be used and the subsequent incorporation of accurately simulated conditions in the experimental rig. In particular the thermal resistances in the rig should be approximately proportional to those existing in the proposed application. The paper outlines ways of measuring normal force, frictional force and wear rates and emphasizes the need to record some variables continuously.

The unstable behaviour of thin-walled unsymmetrical section beams subjected to combined bending and torsion

The investigation described in this paper examines the large displacement behaviour of thin-walled un-symmetrical section beams subjected to combined bending and torsion. The relevant theory is briefly described and a method of theoretical solution is given. The unstable nature of the behaviour is indicated and the requirements and design of a suitable experimental test rig used to verify the theoretical results are discussed. Typical experimental results are shown and compared with the corresponding theoretical values.

Liquid Metal Bearing Performance in Laminar and Turbulent Regimes

The design and development of a high speed journal bearing test rig is described. Test results are presented for water and high temperature liquid potassium lubricated journal bearings. The test program included investigations of bearing torque, lubricant flow rate and stability limits for bearings operating in the laminar regime, through the transition to turbulent flow and in the turbulent flow regime. Torque vs. speed curves were obtained over a range of loads and bearing-journal clearance ratios. The test results are compared with predicted laminar bearing performance. Good correlation with theory was obtained in the laminar regime as indicated by plots of friction parameter vs. Reynolds number at zero load. The transition from laminar flow occurred at higher speeds than predicted by Taylor's criterion under all conditions of load. Recorded bearing torques in the nonlaminar regimes were four to forty times as great as predicted by laminar theory. The results of the materials compatibility study which ...