Press Brake Upper Die

Press Brake Dies: A Simple Guide to Selection and Use

Core Components & How They Work

Upper Die (Press Brake Top Tooling / Bending Machine Punch)

• Acute punch: For small angles or to fix springback

• Gooseneck punch: For deep U-shaped workpieces (avoids interference with pre-bent edges)

Lower Die (V-Groove Die)

• V-groove width affects bending force, fillet size, and quality

• Multi-V dies: One die with multiple V-groove widths (fits different sheet thicknesses)

Working Principle

1. Place the metal sheet on the lower die (usually a V-groove die).

2. The slider drives the upper die (bending machine punch) down.

3. The sheet bends to match the dies’ shape.

4. When the preset pressure is reached, the upper die moves back. Take out the workpiece.

Key Features of Press Brake Dies

• Strong and Wear-Resistant: Made of alloy steel (e.g., 42CrMo) with heat treatment. Hardness is HRC45-HRC50, so it can handle high pressure and friction. Hardened bending segments are extra durable for tough jobs.

• Customizable: Bending machine punches can be made into different shapes (arc, gooseneck punch, acute punch). Lower dies can have different V-groove widths (8mm, 16mm, 24mm) or multi-V dies.

• Good Compatibility: Die size must match the press brake’s clamping system, slider stroke, and tonnage. This includes CNC press brake tools, V-groove dies, and gooseneck punches.

• Standardized: Common press brake tooling (dies, bending machine punches, V-groove dies) has standard sizes. They fit popular brands like Amada and Trumpf. Special tools (custom gooseneck punches, hardened bending segments) can be made to order.

Common Types of Press Brake Dies

By Forming Shape

• Standard Straight Edge Die: For basic straight bending (most common).

• Acute Angle Die (Acute Punch): For small angles or springback compensation.

• Gooseneck Die (Gooseneck Punch): For deep U-shaped workpieces (avoids interference).

• Arc Die: For bending arcs and rounded corners.

• Irregular Shaped Die: Custom-made for special workpiece shapes.

By Application

• Standard Sheet Metal Bending Dies: For common sheets (low-carbon steel, galvanized steel) – cost-effective.

• High-Strength Steel Bending Dies: Thick and hard, for tough materials (stainless steel). Pair with hardened bending segments for better durability.

• Thin Material Specific Dies: Precision-made to prevent warping or scratching thin sheets.

By Installation Interface

• Amada/Promecam Type: Fits Amada press brakes (works with bending machine punches, V-groove dies).

• Trumpf/Wila Type: Fits Trumpf/Wila press brakes (works with CNC press brake tools, hardened bending segments).

• New Standard Type: Universal – fits most domestic press brakes.

How to Choose Press Brake Dies

1. Match the Material

• Mild steel: Little springback – use an 86°–88° acute punch for 90° bending.

• Stainless steel/high-strength steel: More springback – use an 85° acute punch.

• Sheet thickness: Choose the right V-groove die or multi-V die to avoid damage.

2. Follow the "8x Principle" (V-Groove Width)

• Rule: V-groove width (V) = 8 × sheet thickness (T) (good for 3–8mm sheets).

• Thin sheets (T＜3mm): V = 6T (smaller fillet).

• Thick sheets (T＞8mm): V = 10T–12T (reduces pressure, avoids die breakage).

3. Check Pressure Tonnage

• Make sure the tool (die, hardened bending segment, bending machine punch) can handle the press brake’s pressure.

• Do not overload – it will break the die or machine.

• For thick/high-strength sheets: Use thickened dies or hardened bending segments.

4. Choose the Right Punch Shape

• Standard punch: For straight bending.

• Acute punch: For small angles or springback.

• Gooseneck punch: For deep U-shapes (avoids interference).

• Custom punch: For circular/irregular workpieces.

5. Check Equipment Compatibility

• Punch/die shank type must fit the press brake’s clamping system (Amada/Promecam, Trumpf/Wila, New Standard).

• Die height must match the slider stroke and workbench height.

Common Punch Types & Uses

• Standard Acute Punches: Versatile – good for most bending (small radius needed).

• Gooseneck Punches: For deep U-shaped workpieces (avoids pre-bent edge interference).

• Sash Punches: For secondary bending on narrow flanges.

• Sectionalized Tooling (Hardened Bending Segments): Multiple lengths (10mm, 20mm, 100mm) – fits different workpiece widths (good for small batches).

How to Choose the Right Upper Die

• Check the press brake’s interface (Amada/Promecam, Trumpf/Wila, European).

• Calculate tonnage needed (based on sheet thickness) – avoid breaking the punch.

• Punch R-angle: Slightly smaller than the workpiece’s required inner R-angle.

Precautions for Selection

• Do not ignore material springback – it causes wrong angles.

• Follow the "8x rule" for V-groove/multi-V dies – avoids cracking and die damage.

• Ensure tool compatibility with the press brake – prevents installation failure.

• Test with scrap sheets first – adjust parameters to avoid losses.