42crmo Press Brake Tooling

Press Brake Die (Bending Machine Die) Guide

Core Components & Basic Working Principle

Upper Die

• Installed on the bending machine’s movable slider (active pressure part)

• Its shape (standard straight edge, sharp corner, gooseneck, arc, etc.) decides the outer shape of the bent part

• We offer high-performance hardened punch and die options, including 4140 bending dies for enhanced durability

Lower Die

• Fixed on the bending machine’s workbench (fixed support part)

• Mainly has a V-shaped groove (V-groove) structure

• V-groove width directly affects bending force, fillet size and forming effect

Working Principle

1. Place the metal sheet on the lower die

2. The slider drives the upper die to press down vertically

3. The sheet bends to match the shape of the upper and lower dies (irreversible plastic deformation)

4. After reaching the set stroke and pressure, bending is done

5. The upper die returns to its original position, and the workpiece can be taken out

Characteristics of Press Brake Tooling

• High Rigidity & Wear Resistance: Made of alloy structural steel (e.g., 42CrMo), processed by tempering and quenching. Ensures hardness (HRC45-HRC50), load-bearing capacity and wear resistance to handle extrusion force and friction. Our 4140 bending dies are specially treated for extra durability.

• Customizable Molds: Customize punches (arc, gooseneck, irregular shapes) and dies (different V-groove widths: 8mm, 16mm, 24mm) based on workpiece needs (angle, shape, size, material thickness).

• High Matching Degree: Mold specs (height, shank type, installation size) must fit the bending machine’s clamping system, slider stroke and rated tonnage. Forming size must match workpiece drawings.

• Standardization & Serialization: Conventional molds have standard specs (fit Amada, Trumpf, Wille machines) for direct purchase. Special molds can be customized for enterprise needs, including CNC press brake tools.

Common Classifications

By Forming Shape

• Standard Straight Edge Molds: For regular straight edge bending (most widely used)

• Sharp Angle Molds: For small angle bending or springback compensation (high precision)

• Gooseneck Molds: For U-shaped grooves and deep channel workpieces (avoids interference with bent edges)

• Arc Molds: For arc and rounded corner bending (e.g., arc workpieces, transition rounded corners)

• Irregular Shaped Molds: Customized for special workpieces (based on drawings)

By Application Scenario

• Standard Sheet Metal Bending Dies: For ordinary sheet metals (low-carbon steel, galvanized steel; cost-effective)

• High-Strength Steel Bending Dies: Thickened design, high hardness (for stainless steel, high-strength alloy plates)

• Thin Material Specific Dies: Precision machined (prevents warping, deformation, scratching)

By Installation Interface

• Amada/Promecam Type: Fits Amada series bending machines

• Trumpf/Wila Type: Fits Trumpf and Wila series bending machines

• New Standard Type: Universal interface (fits most domestic bending machines)

How to Select Press Brake Die

1. Match Material Characteristics

• Springback Differences:

• Mild steel: Little springback (use 86°~88° punch for 90° bending)

• Stainless steel/high-strength steel: Significant springback (use 85° punch or adjust angle)

• Material Thickness & Die Matching:

• Thin, medium and thick materials need corresponding die specs (avoids damage)

• Common die material: 42CrMo (hardness HRC47-52 after heat treatment; strong and tough)

• Our hardened punch and die options are ideal for various material thicknesses.

2. Follow the "8x Principle"

• Core Formula: Lower die V-notch width V = 8 × material thickness T (ideal for 3-8mm medium-thick plates; smooth fillets, no cracking)

• Adjustments:

• Thin plates (T＜3mm): V=6T (smaller fillet radius)

• Thick plates (T＞8mm): V=10T~12T (reduces bending force; avoids die bursting)

3. Pressure Tonnage Limitation

• Calculation: Combine material thickness, tensile strength and V-groove width to calculate required pressure

• Matching Tips: Bending machine’s actual tonnage must be less than the die’s rated capacity (10%-15% safety margin). Use thickened or segmented dies for thick plates/high-strength steel.

4. Punch Shape Selection

• Conventional Types:

• Standard punch: Regular straight edge bending (most used)

• Sharp-angle punch: Small angle bending/springback compensation

• Gooseneck punch: U-shaped grooves/deep channels (avoids interference)

• Custom Punches: Use arc or irregular punches for circular/irregular workpieces (match workpiece drawings exactly).

5. Installation & Equipment Compatibility

• Shank Type Matching: Choose shank type (Amada/Promecam, New Standard, Trumpf/Wila) that fits the machine’s clamping system.

• Die Height & Stroke Matching: Die height must fit the machine’s slider stroke and worktable height. Confirm interface compatibility for easy installation and accurate positioning. Our CNC press brake tools are designed for perfect compatibility with most machines.

Selection Precautions

• Do not ignore material springback (causes inaccurate angles)

• Follow the "8x Principle" (avoids workpiece cracking and die damage)

• Ensure equipment compatibility (avoids installation failure)