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A commercial process for composite (thermoset) materials has been developed. Key advantages are light weight, low molding pressures, and the ability to accommodate two or more types of reinforcements and one or two resin systems. Partial or complete encapsulation of light-weight cores with tough FRP skin can be obtained. Current and potential applications include light weight, structural automotive, and industrial fiberglass reinforced composites.

The basic raw material used in manufacture of fiberboard is cellulose fiber which is obtained from trees and/or reclaimed (waste) paper. Cellulose fibers are obtained from trees by the “pulping” operation which involves debarking, chipping, and cooking with chemicals to separate the cellulose from other wood components. Cellulose fibers are obtained from reclaimed paper by mechanical repulping in water. Cellulose fibers, once pulped, go through the stock preparation phase where they are cleaned and sent through a refining stage. The conditioned fibers are sent to the paper machine in a water slurry for conversion to paperboard. The paper machine is a large controlled water removal system having four distinctive manufacturing steps: mat formation, pressing, drying, and calendering. The paperboard from the paper machine is sheeted or wound in rolls. It may be sold in this condition or undergo further processing such as laminating or coating before it is sent to the automotive fabricator.

Hydrostatic extrusion has been demonstrated to be a promising method for the manufacture of tubing in a variety of materials. In development studies at Battelle, the process has been used to fabricate tubes from alloy steels, hard aluminum alloys, and titanium alloys. This paper describes the equipment and techniques utilized in hydrostatic tube extrusion, and discusses how the process fits into commercial tube production operations. The potential capabilities for applying the hydrostatic extrusion process as a substitute for hot extrusion or as a substitute for conventional drawing or tube reducing of tubes produced by other means are summarized for a variety of materials.

OUTSTANDING characteristics of magnesium castings are light weight and excellent machinability. Production has increased from about 10,000 lb. in 1925 to approximately 800,000 lb. in 1936. Differences in foundry methods from those practiced for other common metals are pointed out. The mechanical properties are specified, and inspection methods are described. Suggestions are given for proper design of castings. Machining methods and tool design suitable for obtaining the smooth finish, the speeds, and economies that are possible for magnesium-alloy castings are described. Careful painting under approved methods is recommended. Applications of magnesium castings for many parts of aircraft engines, for parts in the fuselage, and in such accessories as aircraft landing wheels and starters are listed, along with other typical applications.

Manufacturer's Flight Testing for Reliabil­ity and Maintainability. Bryan E. Mahon, Flight Test Operations Manager, The Boeing Company. Initial developmental and certification test fly­ing verifies the design, reveals unexpected de­fects, and suggests improvements. Production testing verifies quality control in manufactur­ing. Close attention to test results by the designers is necessary to insure early recognition of problems which would become chronic in service if not corrected. Because of developmental changes, the flight time in a final configuration by the manufacturer is often too short for accu­rate quantitative determination of reliability and maintainability during certification, but good qualitative judgments can be made from ex­perience.

A review of the past, present, and probable future law governing manufacturer’s liability is presented. The most common theories used in asserting claims against manufacturers are negligence and breach of warranty. In explaining negligence, “things of danger if defective” and the extent of a manufacturer’s responsibility are defined and illustrated by examples. Breach of warranty, the most common example of liability without fault, is also discussed.

A new process for the fabrication of Thermal Shields consisting of a continuous layup fabrication process is presented. For this application a relatively new clan of materials called cermet ablatives is discussed briefly. The advent of large booster nozzles, while utilizing much of the current ablative processing techniques derived from smaller nozzles, created a series of joinery problems between metallics and non-metallics because of the size factor alone. Methods of overcoming these joinery problems also are discussed in detail.

The absence of a design and manufacturing template that can be used to develop a product is the basis for this paper. A machine grouping algorithm based on machine utilization factors is discussed. The algorithm was developed based on traditional machine grouping models, but has been modified to use the machine utilization factors to group machines into cells. Different floor layouts for a factory are considered and an optimal floor layout is determined. The WPI World Formula SAE manufacturing facility is used as a model to demonstrate the algorithm. The FSAE competition required the design of an optimal factory layout manufacturing 1000 cars/year. Total costs and times of manufacture for each sub-component of the WPI FSAE racecar are determined. These total times and costs are used to develop the machine and labor requirements for a fictitious company producing 1000 racecars/year. The proposed algorithm is used to group machines into cells on the factory floor.

The patented StressWave cold working process improves the fatigue lives of holes in metal structure by locally treating the metal prior to machining the hole. This important feature, as well as other aspects of the process, offers a number of advantages for manufacturing fatigue-resistant components and assembled structure. Existing manufacturing and assembly equipment can be retrofitted to accommodate various StressWave adaptive devices. These adaptive devices can be actively or passively controlled, work effectively over a wide range of processing speeds and production rates, and can be controlled to adjust for varying thickness of the part or assembly. The flexibility of the StressWave cold working process allows it to be used upstream of final assembly allowing order of magnitude cost reductions when compared to mandrel cold working methods.

The need for lightweight, durable automotive interior trim panels becomes increasingly more important with smaller, lightweight automobiles. The requirements are being accomplished with fiberboard panels produced from reclaimed paper and natural wood fibers. The use of fiberboard panels and manufacturing techniques offers high quality automotive interiors at economical prices.

The purpose of this paper is to explore the challenges and opportunities for auto companies interested in setting up operations in emerging markets. One of the most widely accepted best practices is a concept called LeanThinking (1). This discussion focuses on the implementation of LeanThinking in China. In essence, LeanThinking is a broad management system; when applied to the manufacturing business sector, it is called lean manufacturing.

Discussed in detail are the basic manufacturing operaions for three types of tires: mixing of materials, tread extrusion, fabric calendering, cutting, building, and vulcanizing. For each manufacturing step, cost comparisons are made between two-ply, two-ply bias belted, and two-ply radial constructions. The two-ply tire is the least expensive, with its 9 components, followed by the bias belted tire with 13 components and the radial ply with 18. As the technology advances, the latter two will undoubtably become simpler in construction and, therefore, cheaper.

Structural optimization techniques are more and more used in the design of automotive structures and components. Manufacturing considerations have always been an obstacle to use optimization techniques in a more efficient way. This paper presents to distinguished techniques to include manufacturability in the optimization process. The first technique described is a manufacturing constraint for topology optimization. The second one is the use of topology optimization to reduce the number of spot welds in a vehicle.

PRODUCTION of parts in lots, rather than continuously, may sound like a throwback in the automotive industry, but analysis shows that forgings, stampings, body parts and hardware, replacement parts and other parts are made in lots even in large-production manufacturing organizations. Formulas presented by Professor Raymond determine the size of lot that can be manufactured most economically, and show when the change should be made to continuous production. Consideration is given even to such factors as cost of the space for finished stores and return on the investment in finished parts. The lots indicated are not absolute quantities but are designated in the form of economic ranges that are practicable until there is a marked change in sales or other conditions. The formulas can also be applied to help determine the type of handling equipment that will be most economical to use.

This paper will discuss the effects of manufacturing control programs on the reliability of products. Emphasis will be on reliability as a product characteristic rather than on engineering discipline. The historical mission of the manufacturing function to “make it like the drawing” has been altered by the increased complexity of equipment and processes used to make products and the impracticality of measuring in the final product all characteristics affecting the ultimate function and reliability of the product. The statistics of Reliability Engineering assumes a homogeneity of products which can only be valid with control of manufacturing processes within the known limits of their capabilities. The key functions of Verification communication, training and controls, as they relate to maintaining reliability through the manufacturing cycle, will be discussed.

Many of the vehicle components are manufactured by sheet metal forming process together with joining methods like the spot or seam weld, which will cause work hardening and thermal deformations in the products. As result, undesirable residual stresses, uneven thickness distribution and weld notches can be generated in the final product. Since the fatigue life of an automotive component depends on the manufacturing effects, much care should be given on the estimation of the process effects. In this study, fatigue life of a vehicle suspension component is estimated with finite element methods with considering the stamping and welding process effects. Residual stress distribution due to work hardening and thermal deformation is obtained, and used in determining the fatigue life as the mean stress effect. The simulation result is compared with test result and it shows the fatigue life is affected much more by welding rather than stamping.