Hydroforming isn't as mysterious as it seems. This technology area is full of articles, including case studies, on hydroforming sheet metal and tubular sections.
October 10, 2002
It's difficult to overemphasize the importance of cross section expansion when you're talking about successful and innovative hydroforming of steel tubing. Overemphasizing one aspect of the tube hydroforming design process can take attention away from others and result in less than optimal design....
September 12, 2002
A new type of hydroforming press was recently developed for sheet applications. The new press incorporates data acquisition and control features for research purposes. Current press frame designs for tube and sheet forming are uneconomic for large forces. This press achieves a clamping force of 100 mN, which is absorbed by a single cast frame with a circumferential pretensioning system.
May 16, 2002
Design flexibility is something that all automotive designers want, but too often they lack a thorough understanding of what that means—what aspects of design flexibility apply to a certain part and their effect on cost. A methodology often is adopted when (or even before) a part development...
March 14, 2002
This article discusses tests that are used to evaluate flow stress in tube and why the uniaxial test is not suitable for this application. It discusses a bulge test, which stresses the tube biaxially, including tooling, software, and analysis tools for evaluating stresses.
March 14, 2002
This article discusses an approach to predicting failure in hydroforming prebent aluminum tubes. While strains are well researched for stamping sheet, this type of knowledge is lacking for hydroforming tubular components. Because the strains are different—prebent hydroformed tubular parts experience stress in the axial direction during bending, then in the circumferential direction during hydroforming—new methods for predicting failures are necessary. Researching these methods adds to the knowledge base of hydroforming, helping the technology gain further acceptance in manfacturing.
January 24, 2002
This article examines hydroforming in Germany, focusing on the advancement of the technology. It specifically discusses growing automotive uses, a new type of hydroforming press, material quality requirements, cost factors, new testing methods, and simulation software.
January 10, 2002
The bending characteristics of a tube depend on the material it is made of. Exceeding the allowable limits of this deformation results in unusable parts. The author relates his company's examination and comparison of the bending of two different seamless, extruded tubes: aluminum alloy and steel.
November 29, 2001
T-shapes and Y-shapes are the most commonly hydroformed exhaust system components for automobiles. This article reports on the investigation into the metal flow in Y-shape hydroforming by the Engineering Research Center for Net Shape Manufacturing (ERC/NSM) at The Ohio State University, which conducted several experiments using the tooling available at the SPS research center in Aalen, Germany.
November 15, 2001
This article examines two transitions that are occurring in the automotive industry—the change from stamping to hydroforming, and the substitution of aluminum where steel was used previously.
July 12, 2001
You can use several strategies for starting a hydroforming operation on a limited budget. Review your alternatives for selecting a press, fluid intensification system, and developing the tooling necessary for your operation before you take the plunge.
June 15, 2001
A typical tube hydroforming system is shown in Figure 1. Within this system, a host of factors must be taken into account, from starting tube geometry and material properties to the quality of the final part (such as thickness distribution and dimensional accuracy).