Process Principle
Hydroforming uses liquid pressurization and axial feeding to shape metal tubes into desired forms inside a die cavity. For curved parts, pre-bending is done first.
Classification Types
Three main categories exist: variable-diameter forming for tubes with changing diameters, curved-axis forming for bent components, and multi-port forming for T, Y, U and cross-shaped connections.
Three-Stage Process
First stage places tube in die, seals ends, and fills with liquid to remove air. Second stage applies pressure while feeding material axially until most areas conform to die shape. Third stage increases pressure further to complete corner details.
Key Technical Parameters
Yield pressure starts plastic deformation. Fracture pressure is the failure point. Calibration pressure ensures complete shaping. Feed force is calculated from deformation force, reaction force, and friction. Closing force determines machine selection. Actual feed reaches about 60-80% of theoretical value.
Production Line Components
Four main modules: closing press unit, die set, high-pressure generation system, and electrical control system.
Die Features
Dies have complex structures for multi-point operations, challenging design due to high forces, and strict sealing requirements for production use.
