Experiments designed to answer certain questions about the mechanism of operation and of deactivation of catalysts near stoichiometric conditions were carried out. This involved special catalysts preparations tested in laboratory equipment and in vehicles. We concluded that the poisoning process at exhaust stoichiometry appears to be very similar to the poisoning process under net oxidizing conditions; that is, only a sharply defined outer shell of the pellets is poisoned, this shell progressing inward as time elapses. Based on these experiments, the following catalyst design concept was developed: To utilize the different properties of Pt, Pd and Rh, all three will have to be employed in a special design corresponding to their ratio in ores. To avoid interferences, they should not be coimpregnated over the same support surface; one way to avoid coimpregnation is to impregnate them in separate layers in the catalyst pellets. Due to its relative poison insensitivity Pt should be the outer layer, while Pd and Rh should be protected from the poison front. Consequenty, the Pt impregnation depth (from the outer surface) is given by the depth to which the poisons penetrate. Due to the importance of Rh in catalyzing the NO reduction reaction at the (diffusionmore » controlled) rich end of the A/F scale, Rh should be impregnated as close to the surface of the pellet as possible, while still being protected from poisoning. Consequently, Rh should be impregnated right below the Pt layer and Pd underneath the Rh layer. Due to the transient nature of the feedstream's A/F, it appears to be beneficial to include an agent in catalyst formulations which, by storing and slowly releasing some of the components from the surface, tends to smooth out the effects of A/F oscillations. The results are encouraging; real-time engine dynamometer and vehicle aging tests are required, however, to prove their durability in actual automobile service.« less

Poison-resistant catalysts for the simultaneous control of hydrocarbon, carbon monoxide and nitrogen oxide emissions

The present invention provides an improved attachment system and a method of forming the same. The attachment system typically includes a first member having a first attachment surface and a second member having a second attachment surface. A structural adhesive material is adhered to the first attachment surface and the second attachment surface. Moreover, a sealing material typically seals a gap between the first member and the second member.

Attachment system and method of forming same

A hydroformable frame element is formed from the combination of at least two elements The at least two elements are designed with a partially overlapping region, with an annular space defined within the overlapping region The annular space is filled with adhesive, which is then cured to bond the at least two elements together The adhesive bond is designed to withstand the stresses caused by the hydroforming operation and to retain its strength so that the hydroformed article is then usable as a vehicular frame element

Method of hydroforming articles and the articles formed thereby

Methods and apparatuses are disclosed for applying melt flowable materials to components of articles of manufacture. The methods and apparatuses disclosed herein are concerned with formation of appropriate flowable materials, control over the manner in which the flowable materials are applied, treatment of the components prior to application of the flowable materials and the like. Moreover, the apparatuses and methods may be particularly suited for applying flowable materials to surfaces and components found in automotive, aerospace, and marine vehicles.

Method and apparatus for applying flowable materials

/pdf/deactivation-correlations-of-pd-rh-three-way-catalysts-syhi5sxkuo.pdf

Deactivation Correlations of Pd/Rh Three-way Catalysts Designed for Euro IV Emission Limits : effect of Ageing Atmosphere, Temperature and Time

A structural assembly for a vehicle and method of making same includes a hydroformed tubular member extending axially, a reinforcement disposed within and generally perpendicular to an axis of the tubular member, and at least one securement to secure the reinforcement to the tubular member.

Structural assembly for vehicles and method of making same

A joining operation for a stack of three metal sheets performed using only a single welding step, with access to only one sheet side being required. An inner sheet of the stack has formed therein a pair of bifurcated projections, wherein at least one first apex faces in one direction and at least one second apex faces in the opposite direction. First and second outer metal sheets are assembled with the inner sheet, wherein the first outer sheet abuts the at least one first apex, and the second outer sheet abuts the at least one second apex. A projection welding apparatus welds the sheets, using only access to the first outer sheet superposed the bifurcated projections, wherein a majority of the current flows through the second outer sheet.

Method for one-sided, one step joining of a metal sheet stack

A method of joining tubular members together includes the steps of providing an internal tubular member, providing an external tubular member, and heating the external tubular member and/or cooling the internal tubular member. The method also includes the steps of joining the internal tubular member and second tubular member together to form an overlap region of a joined tubular member, and positioning the joined tubular member between open die halves mating with one another to define a tubular cavity portion. The method includes the steps of progressively closing the die halves to progressively deform the joined tubular member within the tubular cavity portion. The method includes the steps of applying hydraulic pressure to expand and conform the joined tubular member to the tubular cavity portion. The method also includes the steps of separating the die halves and removing the expanded joined tubular member from the die.

Method of joining tubular members

A method is provided for forming a complexly-shaped tubular structure such as a tapered pillar or other structure for a vehicle body. A sheet metal blank having a longitudinal axis is rolled about the longitudinal axis to form a tubular shape and the side edges of the blank are then welded together to form a tube. The tube is then enclosed in a hydroforming die and pressurized to conform the tube to the shape of the die and thereby form the desired complex shape. The sheet metal blank may be formed by the end-to-end welding together of a plurality of separate sheet metal blanks that differ from one another in characteristic including material thickness, material alloy composition, and/or coating. One or more of the blanks can have side edges that are non-parallel so that the tube will taper in diameter along its length.

Joseph M. Lendway

Papers

Method of hydroforming articles and the articles formed thereby

Structural assembly for vehicles and method of making same

Method for one-sided, one step joining of a metal sheet stack

Method of joining tubular members

Method for forming a complex-shaped tubular structure