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Cyclic oligomers of butylene terephthalate (CBT™)† represent a new chemical route to semi-crystalline thermoplastic polybutylene terephthalate (PBT). The oligomers of interest melt completely at about 150°C to produce a low viscosity fluid that is ideal for wetting and dispersing fibrous fillers and reinforcements thereby enabling the development of composites that were previously not possible when working with high viscosity commercial PBT. Introduction of catalyst to undiluted molten cyclic oligomer leads to rapid ring opening polymerization and the formation of high molecular weight thermoplastic PBT without the generation of volatile organic compounds. The polymer resulting from this polymerization will be hereby referred to as pCBT. Treatment of cyclic oligomers in this fashion results in pCBT thermoplastic resin with a high melting point (230°C) and physical performance similar to that of other commercially available PBT resins.

Hydraulic fluid performance, including water-glycols (W/G), is dependent on the chemical composition of the fluid and cleanliness. An overview of W/G fluid chemistry on pump wear is provided here. Also provided, is a brief overview of the impact of fluid cleanliness on the potential wear properties of various components. Finally, an overview of recommended analytical procedures to assure adequate long-term fluid hydraulic and lubrication performance is provided. If these procedures are followed, substantial improvements in hydraulic pump longevity and performance will be realized.

The transportation of large dimension and heavy loads which cannot be moved by rail has generated a requirement for acceptable hauling methods and vehicle specifications. Regulations affecting weight and load distribution have influenced the design of specialized trailers and vehicles for abnormal load hauling. Restriction on the loading of the hauling vehicle's drive axles limits the tractive effort and the ability to move the load, which necessitates the requirement for multiple hauling tractors. Tractor and trailer combinations utilising as many as four hauling vehicles are featured in the requirements for the transportation of up to 400 ton loads. THE DESIGN OF VEHICLES for the movement of abnormal loads will be confined to the requirements of the South African Railways (S.A.R.) for operation throughout the Provinces of South Africa: Cape Province, Natal, The Orange Free State, Transvaal, and South West Africa.

The majority of the pesticide application research carried out in the last ten years has been centered around drift control. The activity of environmental groups and the EPA forced the chemical industry to spend a great deal of time developing methods to avoid criticism and obtain their support. This meant that most of the research dollars were allocated against drift control projects. This situation left a void in research to improve insecticide and fungicide applications. The need to control drift has indirectly resulted in analytical techniques which can be applied to insecticide and fungicide research. Research on improved insecticide and fungicide applications are beginning to come of age. The old “Squirt and look” research techniques are becoming too time consuming and expensive to be practical. For researching new chemical compounds, computers and analytical techniques will reduce the amount of field work needed to screen an application method before it is brought to market.

The use of environmental friendly lubricants is driven by the emergence of regulations appearing in many countries. The absence of water toxicity is of prime importance. To meet the stringent toxicity requirements, it is important to minimize the amount of additives which are potentially toxic. Base stocks of stable fatty chemicals were selected because the inherent properties closely matched the fluid properties required. This would necessitate the use of a minimum amount of additives. Particular attention has been devoted to the following : low temperature stability, proper viscosity, elastomers swelling, resistance to oxidation and parking brake friction. Complex neopolyol esters based on blends of linear saturated fatty acids are good candidates since they closely match the requirements of hydraulic fluids meeting the ecolabel specification. Comparisons with unsaturated derivatives and synthetic petrochemical esters base oils show their advantages.

The author first points out how increasing population and rising standards of living have increased the demand for foodstuffs and how such industrial activities as are brought about by the present conflict magnify the seriousness of the food problem, not only by withdrawing workers from the farms, but also by increasing food consumption on the part of those engaged in the speeded-up industries in order to supply the increased human energy required. The author then passes to a discussion of the tractor as a means for increasing the food supply by taking the place of withdrawn labor and cheapening production. Several charts show the effect of increased individual activity on food consumption, the relation of food consumption to standards of living and the growth of population, the variation of food demand during political activities during the past century, and the relation of the cost per calorie of various cereals.

EXPERIENCE with new plastics for truck bodies reported by these five authors yields a complexity of pros and cons. Among advantages claimed are: 1. High strength-weight ratio. 2. High impact strength and ability to absorb punishment and return to original condition without permanent damage. 3. Ease of maintenance, repair, and cleaning. 4. Good thermal insulation. 5. Resistance to chemical or electrolytic attack or deterioration. 6. Ease of bonding. 7. Adaptability to mass production techniques. Disappointments reported by various users include: 1. High cost of raw materials. 2. Low modulus of elasticity. 3. Low endurance limit. 4. Fractures from internal abrading of reinforcement. 5. Weakening and failure of structures because of poor adhesion between plastic and its reinforcement. 6. Inadequate and faulty engineering knowledge of the subject.Agreement is general, however, that plastics for trucks have a bright future, once the many problems have been ironed out.

The study is carried out through numerical and experimental methods. The finite element method is used to simulate the support mechanical behavior via modal analysis, and for the evaluation of stress concentration regions through pressure and thermoelastic static analyses, and dynamic analysis. The fatigue life is calculated for the presented stresses. Stress, acceleration and temperature data were obtained through dynamic test. For material evaluation, chemical analysis, hardness and metallographic analysis were carried out. For thoroughness, a failed support fractography will be presented. The objective of this study is to correlate the data obtained by numerical method with experimental data, and as a result, the support failure mechanism was identified. A modified support is presented to avoid the failure for the determined loads. The support within the proposed modifications reduces the current maximum stress in 41% and improved the fatigue life in 4.99e5 cycles.

Field Grid Sense is a new system developed for use with a laptop computer to control crop production inputs. The system spatially controls and records field inputs according to regional requirements within the field. Location is identified via the travel lanes formed during field operations. Application rates are predetermined for each field region and stored on computer diskette. The application is adjusted to the assigned value during field operations. This system can be adapted to control/record granular fertilizers, direct chemical injection systems, liquid fertilizers, seed planters, crop yield maps, and/or any field input that needs to be spatially managed. The use of equipment and/or products in this study is not intended to endorse or discredit the manufacturer or product by the researchers, SDSU, and/or SAE. This pulication has been approved by the South Dakota Agricultural Experiment Station as Journal Article No. 2509.

A program of research on diesel smoke and odor was sponsored by the U.S. Public Health Service by contract with Southwest Research Institute. A test facility was developed in which full-scale trucks and buses were operated on a chassis dynamometer through operating modes that yielded maximum exhaust smoke and odor. A system of exhaust dilution was employed to provide realistic odor concentrations to a panel of judges who rated the intensity and quality of the exhaust in terms of a set of chemical standards. Smoke levels were measured with a PHS-designed full-flow optical smokemeter. After an initial baseline evaluation of groups of buses and trucks with standard engines, various control techniques were evaluated to determine their effectiveness in reducing smoke and/or odor. Chemical analyses of the exhaust were made for the purpose of correlating the smoke and odor reductions with changes in exhaust composition.

All previous correlations of the ignition delay (ID) period in diesel combustion show a positive activation energy, which means that shorter ID periods are achieved at higher charge temperatures. This is not the case in the autoignition of most homogeneous hydrocarbons-air mixtures where they experience the NTC (Negative Temperature Coefficient ) regime in the intermediate temperature range, from about 800 K to 1000 K). Here, the autoignition reactions slow down and longer ID periods are experienced at higher temperatures. Accordingly the global activation energy for the autoignition reactions of homogeneous mixtures should vary from positive to negative values.

The sealing of electrical splices in heavy equipment has become an important element in increasing the life and reliability of both on and off-the-road vehicles. Adhesive lined heat shrink tubing is an effective protective and sealing method for these splices; it protects splices from the mechanical, electrical, chemical and temperature environments that exist in heavy equipment operation. In addition, the tubing meets the production requirements of reproducible installation at production rates and low installed cost. This paper will focus on one heat shrink tubing system which was designed for the sealing of vehicular electrical splices. It will discuss the design requirements, manufacturing methods and installation techniques and mechanisms for this heat shrink tubing system.

No more molecules! Companies continue to invest in new chemistries for EV batteries, but at least one company in the battery industry thinks it's time to halt the unending search for new chemical formulations and focus on driving down processing costs.

A model in aftertreatment A look at 1-D numerical models, based on chemical kinetics derived for real-world catalysts, for a vanadium oxide ammonia SCR catalyst and a PGM-based DOC.

No stopping global design Global teams ride down the cyber highway. Engines play clean in the flight to meet increasing regulations Sensors, faster CPUs help reduce emissions while maintaining performance. Hydraulics have the power to control The latest generation of hydraulic systems provides an effective alternative to other forms of motion control. A home away from home Technology advances help to make equipment operators more comfortable- and more and more productive- in hte field, in the pit, and on the job site. Ryan's 'Research' put to good use The Southwest Research Institute engineer assumes SAE President duties for 2008. Biofuel effects As the off-highway industry in Europe prepares for the introduction of biofuel, specialists are attempting to anticipate potential mechanical and chemical problems it may bring to powertrain systems and component operation- and prepare the answers.

Rolling contact fatigue lives of various steels used for medium- and large-sized bearings were investigated, using Φ60×ι90 specimen. Through hardened steels and induction hardened steels have nearly the same life, while carburized steels have lives about 3 times as long as that of through hardened steels. Since rolling contact fatigue life is affected by the cleanliness most significantly, it is most important to use clean steels for good bearing life. The influence of chemical compositions upon rolling contact fatigue life varied with cooling speed during quenching of the specimen. Using a steel which has excessively high hardenability for a small-sized bearing leads to a poor rolling contact fatigue life. For a medium or large-sized bearing we have to use a steel which has high hardenability necessary for the thickness of the bearing, but it seems unnecessary to pay close attention to the steel type.

Trials of remote controlled bulldozers show them to be easy to operate. Military advantages of remote controlled bulldozers are: battlefield construction; breaching chemical, radiological, or biological barrier zones; fire fighting; and negociating polar terrain. Commercial applications are: open pit mining; fire fighting; operations in toxic atmospheres; and others.

Low viscosity engine oils are considered a feasible solution for improving fuel economy in internal combustion engines (ICE). So, the aim of this study was to verify experimentally the performance of low viscosity engine oils regarding their degradation process and possible related engine wear, since the use of low viscosity engine oils could imply higher degradation rates and/or unwanted wear performance. Potential higher wear could result in a reduction in life cycle for the ICE, and higher degradation rates would be translated in a reduction of the oil drain period, both of them non-desired effects. In addition, currently limited data are available regarding “real-world” performance of low viscosity engine oils in a real service fleet.