The operating principle of the fully automatic gantry straightening machine for alloy steel, carbon steel, and stainless steel round bar blanks revolves around a closed-loop process of "Precise Detection - Intelligent Analysis - Targeted Force Application - Stress Relief." By adapting to material characteristics, it achieves efficient and accurate straightening, which can be broken down into four key steps:

1. Workpiece Positioning and Bending Detection: Establishing the Straightening Reference

The equipment uses a fully automatic feeding mechanism (such as a gantry or mechanical gripper) to transport the round bar blank to the detection station within the gantry frame. Then:

• Multi-Point Support: Employs 3-6 adjustable support points to lift the workpiece, ensuring stable placement of alloy steel, carbon steel, and stainless steel round bars of different diameters (e.g., Φ50-Φ300mm) to prevent additional bending due to self-weight;
• High-Precision Detection: Uses laser diameter gauges, displacement sensors, or dial indicators to perform multi-point scanning along the axial direction of the round bar, collecting real-time data on bending degree, bending position (e.g., center bending, end bending), and deviation values (e.g., 0.5-2mm bending amount). Data is directly transmitted to the PLC control system;
• Material-Specific Adjustment: The system automatically optimizes detection pressure based on preset material parameters (e.g., yield strength of alloy steel, elastic modulus of stainless steel). For example, higher preload pressure is applied for rigid carbon steel to prevent displacement during detection, while polyurethane detection contacts are used for scratch-prone stainless steel surfaces to avoid damage.

2. Data Processing and Straightening Plan Generation: Customized Force Application Strategy

After receiving the detection data, the PLC control system, combined with its built-in "Material - Bending Amount - Force Application Parameters" database, generates a targeted straightening plan:

• Stress Analysis: For uneven internal stress in alloy steel (e.g., 40CrNiMo), residual cold-bending stress in carbon steel (e.g., 45 steel), and machining stress in stainless steel (e.g., 304), the system uses algorithms to simulate deformation trends under force, determining the sequence of "stress relief first, precise straightening next";
• Force Parameter Calculation: Automatically sets the pressure of the straightening cylinder (e.g., 10-30MPa for high-strength alloy steel, 8-25MPa for carbon steel, 5-20MPa for stainless steel), the force application point (corresponding to the maximum bending area), and the pressure holding time (e.g., 2-5 seconds to ensure sufficient deformation of ductile materials like stainless steel);
• Multi-Station Coordination: If the workpiece has multiple bends (e.g., center and end bending in long alloy steel bars), the system plans the action sequence of multiple force application stations to avoid excessive single-point force leading to fracture or excessive plastic deformation.

3. Targeted Pressurization and Straightening: Correcting Bending Deviation

According to the generated straightening plan, the hydraulic cylinders on the gantry frame (typically 2-4, distributed above/below or on both sides of the workpiece) perform targeted pressurization:

• Flexible Force Application: Uses a servo hydraulic system to precisely control cylinder thrust, avoiding impact damage to brittle materials like carbon steel. Meanwhile, to accommodate the corrosion resistance of stainless steel, cylinder piston rods are chrome-plated or coated with ceramic to prevent hydraulic oil contamination on the workpiece surface;