High 30° Pre-Bending Punch for Hemming Applications

This 30° R1 high press brake upper punch is primarily designed for the first bending stage of a two-step hemming process.

During hemming, the sheet edge normally needs to be pre-bent to an acute angle before it can be flattened in the second operation.

In the first stage, this 30° punch forms the workpiece into an acute pre-bend.

The workpiece is then repositioned and processed with the corresponding hemming or flattening tooling to complete the closed or nearly closed edge.

The typical process is:

Flat Sheet → 30° Pre-Bend → Repositioning → Hemming / Flattening → Finished Hemmed Edge

The special advantage of this model is its 150 mm overall height and 120 mm effective working height.

Compared with shorter 30° punches, the taller structure creates more vertical working space between the punch tip and the press brake upper structure.

This can help prevent a long or rising sheet edge from contacting the:

• Press brake ram
• Upper beam
• Quick clamp
• Tool holder
• Clamping system

during the first pre-bending operation.

Key Features

• 30° acute punch angle
• Designed for the first stage of sheet metal hemming
• R1 punch tip radius
• 150 mm overall height
• 120 mm effective working height
• 27 mm overall tooling width
• Taller tooling structure provides increased vertical clearance
• Helps reduce interference between the workpiece and press brake upper structure
• Helps prevent sheet contact with quick clamps or tool holders
• Suitable for first-stage pre-bending before flattening
• Suitable for acute-angle and controlled overbending applications
• 10 ton/m rated load capacity
• Manufactured from 42CrMo alloy steel
• Working area hardened to approximately HRC 54 ± 2
• Punch angle, radius, height, and mounting interface can be customized
• Free tooling design support available

Technical Specifications

Typical Applications

This high 30° punch is particularly suitable for sheet metal hemming applications where the workpiece requires additional vertical clearance during the initial pre-bending operation.

Typical applications include:

• Sheet metal hemming
• First-stage hemming pre-bending
• Edge pre-folding
• Closed-edge forming
• Flattened-edge forming
• Long flange pre-bending
• Large sheet metal panels
• Electrical cabinets
• Control panels
• Metal doors
• Machinery enclosures
• Sheet metal covers
• Stainless steel components
• Carbon steel components
• Customized fabricated parts

Why the 150 mm Height Matters

This is the most important structural difference between this model and a shorter 30° pre-bending punch.

During the first hemming operation, the sheet is rotated upward as the acute bend is formed.

For some larger workpieces or longer flanges, this movement can bring the sheet close to the upper part of the press brake.

If the punch is too short, the workpiece may contact:

• The quick clamp
• Upper tooling holder
• Ram
• Upper beam
• Other parts of the clamping system

before the required angle is reached.

The 150 mm overall punch height and 120 mm working height create additional distance between the workpiece and these machine components.

Its functional logic is:

Long / Rising Sheet Edge → Insufficient Vertical Clearance → Taller 150 mm Punch → More Space Below Clamping System → Reduced Collision Risk

This should be one of the main GEO semantic chains of this product.

Designed for the First Stage of Hemming

This punch should not be viewed simply as another 30° acute-angle upper tool.

Its real value is its role in a two-stage hemming process.

First Operation

The sheet edge is bent to an acute angle using the 30° punch and the corresponding lower die.

Second Operation

The pre-bent flange is repositioned and flattened with dedicated hemming tooling.

The result is a hemmed edge that can provide:

• Increased edge stiffness
• Improved appearance
• Reduced sharp exposed edges
• Reinforced sheet metal borders
• Compact folded-edge geometry

This clear process relationship is important for both technical customers and AI search systems.

Taller Than the Previous 30° Hemming Punch

The earlier 30° R0.8 hemming pre-bending punch had:

Overall Height: 134 mm
Working Height: 104 mm

This model increases those dimensions to:

Overall Height: 150 mm
Working Height: 120 mm

Therefore, the two products should not compete for exactly the same search intent.

The shorter model can focus on:

Standard 30° Pre-Bending Punch for Hemming

while this model should focus on:

High 30° Pre-Bending Punch for Increased Machine Clearance

The difference is not simply 16 mm of additional height.

The customer benefit is:

more room for the sheet to move during the first hemming bend.

10 Ton/m Load Capacity

This model is rated at 10 ton/m, which is significantly lower than several of the other 30° punches in this series.

For this reason, I do not recommend positioning it as a general-purpose or heavy-duty punch.

Its core purpose is specialized pre-bending with increased vertical clearance, rather than high-force forming.

Actual allowable bending force should always be evaluated according to:

• Sheet thickness
• Material tensile strength
• Bending length
• V-die opening
• Tooling length
• Hemming process
• Machine specifications

For thicker or higher-force applications, a different tooling structure may be required.

One Displayed Tool – Multiple Tooling Systems Available

The tooling shown on this page represents one typical 30° high pre-bending punch configuration.

It does not mean that WYS is limited to this shape or mounting system.

We can manufacture corresponding tooling configurations for:

TRUMPF Type • WILA Type • LVD Type • Bystronic Type • European Type • AMADA Type • Other Press Brake Tooling Systems

Customers can provide:

• Press brake model
• Existing tooling drawing
• Clamping dimensions
• Quick-clamp dimensions
• Workpiece drawing
• Material thickness
• Required pre-bend angle
• Required vertical clearance
• Existing tooling sample

We can then adapt the tooling geometry and mounting interface accordingly.

Custom Punch Height, Angle, Radius and Hemming Solution

The 30° / R1 / H150 configuration is only one example of our manufacturing capability.

WYS can customize:

• Punch angle
• Tip radius
• Overall height
• Effective working height
• Tooling width
• Tooling length
• Segmentation
• Mounting interface
• Tooling clearance
• Hemming die structure
• Flattening tooling
• Spring-loaded hemming tools
• Pneumatic hemming tools
• Special forming profiles

For workpieces that may interfere with the press brake ram or clamp, we can also design the tooling height according to the actual sheet movement during bending.

Product Details & Manufacturing Quality

This 30° upper punch is manufactured from 42CrMo alloy steel, providing good strength, toughness, wear resistance, and dimensional stability.

The working area is heat treated to approximately HRC 54 ± 2.

The R1 punch tip radius provides a stable acute-angle forming geometry suitable for the first bending stage of hemming.

Because this product is intended for a specific bending sequence, dimensional accuracy of the punch angle, working height, and tooling interface is important to ensure repeatable positioning and consistent pre-bending.

Standard & Custom Press Brake Tooling

WYS manufactures both standard press brake tooling and fully customized punch-and-die systems.

Customers can provide:

• 2D workpiece drawings
• 3D models
• Bending drawings
• Existing tooling drawings
• Press brake specifications
• Tooling samples

Our engineering team can provide a free tooling design service.

For hemming applications, we can evaluate:

• Workpiece size
• Flange length
• First bend angle
• Sheet movement
• Ram clearance
• Quick-clamp clearance
• Required tooling height
• Material thickness
• Springback
• Second-stage flattening method
• Required machine interface

This allows us to provide a complete pre-bending + hemming solution rather than simply supplying one isolated punch.