The task of this thesis is to test different adhesives uses in electrical drives for high performance applications. The purpose is to investigate possible replacements to the current used adhesive which will be obsolete in short term. This task is approached by first doing a literature search for typical testing methods for adhesives and which ones are appropriate for Moog. Then, a test rig is designed to accomplish the tests. Finally, the tests are evaluated and analysed to find out the best replacement adhesive.

The first part of the master's thesis deals with basic types and functions of dampers, together with a search of commonly used methods of damper force measurements. Consequently, a design of an on-road damper force measuring assembly is made and positioned onto a 3D model of a vehicle's damper. In the final part of the thesis there is made an evaluation of conditions of use of the measuring assembly together with its versatility.

Feed water heaters are large shell and tube heat exchangers. They from part of the Rankine cycle used in coal fired power plants with the main purpose being the improvement of the overall cycle efficiency. Like most heat exchangers, feed water heaters suffer from fouling. Fouling is defined as “any undesirable deposit on heat exchanger surfaces that increases resistance to heat transmission”. In the design of heat exchangers, fouling is accommodated by adding additional surface area to the heat exchanger. The amount of additional area is determined by the use of fouling factors. Although this is the only wide-spread method accepted in industry, the fouling factors in use are outdated, generally considered conservative and lead to oversized heat exchangers. The purpose of this study was to design and build a test rig that can accurately measure fouling factors of feed water heater tubes that has been in service for a full life cycle. A comprehensive literature study was performed to decide on the most effective test method, as well as the required instrument type and accuracy. The best method was found to be where the overall heat transfer coefficient for a fouled tube, outside cleaned tube (half clean) and clean tube was measured. The measured values are then converted to the internal, external and overall fouling factors. Validation test were done on the test rig. These included energy balance tests, theoretical comparison tests and repeatability tests. The results of all tests were acceptable and within measurement uncertainty limits. Five sample test tubes, obtained from a 30 year old LP heater at an Eskom power station, were tested. The results indicated that the average measured fouling factors were less than 20% of the commonly used HEI fouling factors. This is significantly lower and confirms that the fouling factors in use for this specific case are conservative. The test rig proved to be accurate and effective in measuring the fouling factors. Although the tests shows promising results, the small amount of tubes tested from only one heat exchanger are not sufficient to make meaningful conclusions. The test rig is now ready for a future study where a large sample of tubes can be tested.

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The exhaust valve system of combustion engines experiences a very complex contact situation of frequent impact involving micro sliding, high and varying temperatures, complex exhaust gas chemistry and possible particulates, etc. In addition, the tribological situation in the exhaust valve system is expected to become even worse due to strict future emission regulations, which will require enhanced combustion and cleaner fuels. This will substantially reduce the formation of combustion products that might ease the contact conditions by forming tribofilms on the contacting surfaces. The lack of protective films is expected to result in increased wear of the contact surfaces. The aim of the work presented in this thesis has been to increase the tribological understanding of the valves. The wear that takes place in the valve sealing interface and how the change in operating conditions affects it have been studied. Such understanding will facilitate the development of future valve designs. A test rig has been developed. It has a unique design with the ability to insert ppm amounts of media into a hot air flow, in order to simulate different environmental changes, e.g. varying amount and composition of combustion residue particles. PVD coated valves were evaluated in a dry atmosphere. It was concluded that although some of the coatings showed potential, the substrate could not support the thin, hard coatings. Investigations with an addition of different oils have been performed. Fully formulated oils proved to build up a protective oil residue tribofilm. This tribofilm has been in-depth analysed and proved to have similar composition and appearance as tribofilms found on low wear field tested valves. With a non-additivated oil, wear particles from the valve seat insert formed a wear particle tribofilm on top of the valve sealing surface. Without any oil the surfaces showed severe wear with wear particles spread over the surfaces. The results presented give a hint about what to be expected in the future, when the engine oils are replaced with ash less oils with reduced amount of additives and the consumed amount of oil within the cylinders are reduced.

Equipment failure and well deviations are prevailing contributors to production delays within the petroleum industry. Particular monetary focus is given to the drilling operations of wells to overcome these deficits, in order to extract natural resources as efficiently, and as safely, as possible. The research presented here focuses on minimizing vibrations of the drill string near the bottom-hole assembly (BHA) by identifying the cause of external forcing on the drillstring in vertical and horizontal wells and measuring the effects of various factors on the stability of perturbations on the system. A test rig concept has been developed to accurately measure the interaction forces and torques between the bit, formation and fluids during drilling in order to clearly define a bit/formation interface law (BFIL) for the purpose vibrational analysis. As a secondary function, the rig will be able to measure the potential inputs to a drilling simulation code that can be used to model drillstring vibrations. All notable quantities will be measured including torque on bit (TOB), weight on bit (WOB), lateral impact loads (LIL), formation stiffness, bit specific properties, fluid damping coefficients and rate of penetration (ROP). The conceptual design has been analyzed and refined, in detail, to verify its operational integrity and range of measurement error. The operational envelope of the rig is such that a drill bit of up to 8 ½ inches in diameter can be effectively tested at desired operational parameters (WOB: 0-55,000 lbf, RPM: 60-200) with various rock formations and multiple fluid types. Future use and design possibilities are also discussed to enhance the functionality of the rig and the potential for further research in the area of oil and gas drilling and vibrational modeling.

This thesis is based upon one project, STEP (Sealing Technology – Enhanced Properties), inside ABB Corporate Research, Sweden, which is aiming to study the sealing technology of robotic implementation by a scientific/systematic approach. Nowadays the radial lip seal can be found in many fields such as automobiles, aero-planes, and marines, etc., and they have evolved into different designs and materials for the past several decades. Most of them are designed for conventional applications like cars, in which the shaft usually works in continuous rotary motions, and with such conditions lip seals could normally function well due to the sealing mechanism. However, regarding the robotic application, in which the shaft typically works in bi-directional and intermittent motions, the lip seal may not perform ideally and sometimes cause additional leakage. Hence, this thesis is mainly focused on an experimental approach to study the lip seal performance with controlled parameters, especially the robotic motion, together with other parameters, such as oil, temperature, pressure, etc. The work includes literature survey of lip seals, specifying the test rig, building the test rig, developing a leakage detection system, carrying out benchmark tests and seal tests with different robotic motions. / Detta examensarbete är baserat på ett så kallat STEP-projekt (Tätningsteknik – förstärkande egenskaper), inom ABB Corporate Research i Sverige, med syftet att studera tätningsteknik för robottillämpningar på ett vetenskapligt/systematiskt sätt. I dagsläget används radiella läpptätningar inom många områden, såsom fordons-, flyg- och fartygsindustri. Under de senaste decennierna har den vidareutvecklats och är nu gjord av flera olika material. De flesta är utformade för konventionella tillämpningar, som exempelvis fordon. Där arbetar axeln vanligen imedkontinuerligt roterande rörelser, och vid sådana förhållanden kan läpptätningar normalt fungera väl. Men när det gäller robottillämpningar, där axeln typiskt arbetar i dubbelriktade och intermittenta rörelser, fungerar läpptätningen inte idealt och kan även ge oönskat läckage. Detta examensarbete är fokuserat på att utveckla en experimentell metod för att studera läpptätningars prestanda med väl kontrollerade parametrar, såsom oljans egenskaper, temperatur, tryck, o.s.v. I arbetet ingår litteraturstudie av läpptätningar, specificering av testrigg, byggande av testrigg, utveckling av ett system för att detektera läckage, utförande av benchmark-tester, samt tätningsprov för olika robotrörelser.

Dellner couplers AB is a developer and producer of railway coupling systems. This project is a master thesis that focuses on improving the quality, quantity and efficiency of their test department. This project details the design and development of a multi functional test rig that would serve as a basis for expansion decisions of the test department at Dellner. The resulting design was developed using the product development process by Ulrich and Eppinger with different phases. The phases being project planning, concept development, system-level design, detail design, testing and refinement and production ramp-up. However, some phases as described by the method would be altered or skipped for this project because of the limitations of the project and the nature of the product. The resulting design is able to perform four different tests that Dellner utilises today. This shows the potential of replacing four large test rigs with one of the new design. The design also has many different configuration options that enables an expansion of different types of tests. Simulations and calculations were made in order to verify the strength and functionality of the design.

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