Hydroforming

About: Hydroforming is a research topic. Over the lifetime, 2796 publications have been published within this topic receiving 26293 citations. The topic is also known as: Bulge forming.

Aluminium-alloy pipe shaping method

Abstract: A technology for making Al-alloy pipe by use of a hydroforming machine with die and left and right T-shaped tubes includes such steps as putting a raw Al-alloy pipe in the die composed of upper and lower dies, inserting the T-shaped tubes in its both ends, filling liquid oil via said T-shaped tubes, pushing the T-shaped tubes to remove excessive liquid oil and air, filling high-pressure liquid oil to expand the Al-alloy pipe, and unloading the finished Al-alloy pipe.

Electromagnetically activated high-speed hydroforming process: A novel process to overcome the limitations of the electromagnetic forming process

Abstract: In this paper, a novel electromagnetically activated high-speed hydroforming process (EAHF) is introduced. The EAHF process is compared with the electromagnetic forming process (EMF) in the forming of a low-conductive steel sheet, forming of a high-conductive thin aluminum sheet and also, in the multistage forming of an aluminum sheet. Furthermore, the effect of the process parameters on the EAHF process is investigated by the Taguchi design of experiments. Based on the results it can be concluded that the presented process is an efficient high-speed forming process that can be used for metals and non-metals with low electrical conductivity. This process has more uniform pressure and hence more uniform geometry compared to the EMF process. Furthermore, by a proper design of the process, EAHF can be used for the simultaneous forming and trimming operation.

Apparatus and method for hydroforming a tubular part

Abstract: A method and apparatus for shaping a raw tube (40) into a formed part. The part can be configured within a die assembly including a hydroforming die structure (12, 14) and a pair of tube-engaging punches (81). The punches are inserted into the ends of the raw tube to shape the ends into the desired configuration. The middle portion of the raw tube is shaped into the desired configuration by hydroforming. Thus, the method and apparatus can shape the raw tube along its entire length, leaving no remnants of the raw tube that must be trimmed away.

Hybrid forming of sheet metals with long Fiber-reinforced thermoplastics (LFT) by a combined deep drawing and compression molding process

Abstract: In this article, a newly developed method for forming metal sheets together with long fiber-reinforced thermoplastics (LFT) to hybrid parts is presented. The idea of combining two different materials in one part is nothing new, but most of the existing processes use at least separate production techniques for each material and an additional joining operation. The special characteristic of this new process is realized by a combined forming tool for both sheet metal and LFT to create a hybrid part with only one necessary and simultaneously executed process step. Besides contact to the punch, the metal sheet is also formed by the molten LFT material, which behaves like a hydraulic fluid in hydroforming processes. With this method, it is possible to reduce the thickness of sheet metal components by adding a LFT reinforcement structure. The interface connection between the metal sheet and LFT is realized by using a bonding agent, which is previously applied to the metal sheet via coil or powder coating. To achieve this hybrid forming process, new tool and sealing concepts have been developed and the corresponding process parameters were identified and optimized. As a result, the innovative process offers a cost- and time-efficient solution for multi-material lightweight design.

Analytical Model for the Characterization of the Guiding Zone Tribotest for Tube Hydroforming

Abstract: Common part failures in tube hydroforming include wrinkling, premature fracture, and unacceptable part surface quality. Some of these failures are attributed to the inability to optimize tribological conditions. There has been an increasing demand for the development of effective lubricants for tube hydroforming, due to widespread application of this process. This paper presents an analytical model of the guiding zone tribotest commonly used to evaluate lubricant performance for tube hydroforming. Through a mechanistic approach, a closed-form solution for the field variables contact pressure, effective stress/strain, longitudinal stress/strain, and hoop stress can be computed. The analytical model was validated by the finite element method. In addition to determining friction coefficient, the expression for local state of stress and strain on the tube provides an opportunity for in-depth study of the behavior of lubricant and associated lubrication mechanisms. The model can aid as a quick tool for iterating geometric variables in the design of a guiding zone, which is an integral part of tube hydroforming tooling.Copyright © 2008 by ASME