Search

Welding of sheet metal structures in the automotive industry involves inflexible and expensive clamping devices to properly position and fasten the parts. The approach of feature-based fixturing can reduce fixtures in the joining process. It is based on part-inherent fastening features that realize the fixture functions. The proper design of these features requires knowledge of forces that result from the joining process and thus need to be compensated. For this paper, process forces were investigated during remote laser beam welding. This was achieved by using a thermomechanical simulation model. The aspects described in this paper are model build-up and validation, application of the approach to a real structure, and affiliated parameter studies. The studies show that required clamping forces depend, among other things, on the clamping condition and on the weld strategy. Finally, the simulation model allows for the design of fastening features to reduce joining fixtures in the automotive body shop.Welding of sheet metal structures in the automotive industry involves inflexible and expensive clamping devices to properly position and fasten the parts. The approach of feature-based fixturing can reduce fixtures in the joining process. It is based on part-inherent fastening features that realize the fixture functions. The proper design of these features requires knowledge of forces that result from the joining process and thus need to be compensated. For this paper, process forces were investigated during remote laser beam welding. This was achieved by using a thermomechanical simulation model. The aspects described in this paper are model build-up and validation, application of the approach to a real structure, and affiliated parameter studies. The studies show that required clamping forces depend, among other things, on the clamping condition and on the weld strategy. Finally, the simulation model allo...

The aim of the present study was the environmental and health risk assessment of the oil contaminated soil in the Mexican tropic. The case is based on the total petroleum hydrocarbons (TPH) and polycyclic aromatic (PAH) soil contamination resulting from the activities of the oil industry over 70 years. The results of this study were estimated using CalTOX, a multimedia exposure model. The aromatic fraction constituted by PAH of two, three, four and five rings presented concentrations from 0.005 to 3.84 mg/kg. The BaP was the chemical of major concern due to its high carcinogen potential. The health risk assessment with CalTOX showed that risk mainly came from two exposure pathways: dermal uptake and ingestion. Only one zone was classified in the high risk level and rest of the zones did not exceed the acceptable health risk value (>10-E6) without requiring remediation actions. The environmental compartment that required main attention was the surface soil. [Received: September 22, 2009; Accepted: December 8, 2009]