Precision 42CrMo Spring-Loaded Hemming Tools: 2-in-1 Bending & Flattening Compound Dies

Achieve flawless, zero-gap dead folds and safety edges without changing tools between cycles. The ALAS Precision Spring-Loaded Hemming Tooling is a high-performance compound die engineered specifically for high-mix fabrication. By integrating an acute bending V-groove and an lower cushioning flattening anvil into a single spring-loaded mechanical assembly, this tool allows operators to pre-bend and flatten sheet metal edges in one smooth continuous stroke, cutting processing cycle times by up to 50%.

Dynamic Spring-Loaded Mechanism Explained

Unlike traditional rigid flattening blocks, the ALAS compound hemming tool utilizes heavy-duty internal die springs to manage structural movements seamlessly during the dual-stage bending cycle:

• Stage 1 (Acute Pre-Bending): The upper punch presses the sheet metal into the top acute V-groove, achieving a crisp pre-bend angle (typically 30° to 45°). During this phase, the internal high-tension springs hold the lower block firmly in its extended position.

• Stage 2 (Flush Flattening): The upper die carrier retracts smoothly into the lower housing block (which has a 65mm base profile), utilizing its 15mm dynamic stroke to allow the flat shoulders to crush the pre-bent flange flat against the horizontal anvil face.

Explicitly Optimized Application Scenes

This precision compound tooling is the ideal choice for high-end sheet metal lines where operator safety, edge rigidity, and pristine cosmetic finish are non-negotiable:

• Safety Flanges & Enclosures: Perfect for fabricating commercial electrical cabinets, lockers, steel furniture, shelving, and laboratory equipment to completely eliminate sharp sheet edges.

• Cosmetic Surface Protection: Specially optimized for stainless steel, architectural aluminum, and pre-painted panels where sliding friction scratching must be strictly controlled.

• Door & Box Panel Reinforcements: Ideal for creating double-thickness structural hems along the perimeter of box plates to maximize overall sheet rigidity.

Forged 42CrMo Metallurgy with CNC Ground Finishes

To endure the severe crushing tonnages required for uniform hem flattening, every ALAS compound tool is manufactured to strict industrial standards:

• Premium Material Core: Forged from genuine 42CrMo alloy steel (equivalent to AISI 4140) for supreme tensile strength and zero risk of cross-sectional cracking under off-center loads.

• Precision Hardening: Fully quenched and tempered body, combined with high-frequency induction hardening on the critical V-shoulder and crushing faces to achieve a stable HRC 47±3.

• Ultra-Smooth Contact: Precision ground surfaces finished down to ≤ Ra 0.8 μm, minimizing friction and material galling when processing mirror stainless steel.

Technical Specification & Dimensional Layout

Our standard configuration is fine-tuned to fit seamlessly into mainstream hydraulic press brake setups. Please refer to the dimensional breakdown below based on our factory blueprints:

Compatibility & Factory Customization Options

Every ALAS spring-loaded hemming die is available in flexible length configurations to match your exact part geometries on the shop floor:

• Full-Length Integral Blocks: Stocked in standard 835mm and 1000mm single pieces for long, seamless straight-line edge folding.

• Precision Segmented Kits: Assembled via multi-piece fraction blocks (e.g., 10, 15, 20, 40, 50, 100, 200, 300 mm) to form closed four-sided boxes without flange collision.

• Bespoke Adaptations: Fully customizable base shanks and mounting pins to guarantee direct compatibility with Amada/Promecam, Trumpf, Wila, LVD, and Durma clamping systems.

Ordering Note:When submitting your request, please verify your press brake's minimum shut height to ensure the 110mm tool height fits within your operational daylight envelope. Complete spring tension certificates and rated load limits are provided with every factory shipment.