Services de pliage des métaux

The choice depends on stock form and bend geometry.

Press brake bending is the default for sheet and plate from 0.5 to 12 mm thick. Used for enclosures, brackets, channels, and flanges where flat blanks need angled features. Bend angle tolerance ±0.5° standard, ±0.25° with adaptive control.

Tube bending (rotary draw with mandrel) is used for round, square, and rectangular tubing where the wall must stay round through the bend. Standard for handrails, exhaust runs, roll cages, and structural frames in tubular stock.

Roll bending produces cylinders, cones, and long-radius arcs in plate or bar from 1 to 25 mm. Stretch forming is added when the part has compound curvature, such as aerospace skin panels.

Most production assemblies use two processes: press brake for the flat panels and tube bending for the framework. Our DFM review can recommend the right combination during quoting.

Tolerance depends on bending method, material, and number of bends in sequence.

Press brake bend angle holds ±0.5° standard and ±0.25° with adaptive press brakes that measure angle in real time. Positional accuracy on flange length holds ±0.05 mm with proper back-gauge calibration.

Tube bending centerline radius holds ±0.5 mm typical, with bend angle accuracy ±0.5°. Wall thinning on the outside of the bend ranges 10 to 20 percent depending on bend radius and material.

Roll bending diameter and ovality hold ±1 mm on cylinders up to 1,000 mm, looser on larger diameters.

Each bend in a multi-bend part introduces a small cumulative error, so parts with five or more bends should have tolerances reviewed during DFM. Over-tolerancing every dimension drives up cost without improving fit.

Metal bending works on most ductile metals.

Mild and carbon steel from 0.5 to 12 mm bends readily on standard press brakes. SPCC, A36, Q235, and S235JR are the cost leaders for structural and bracket work.

Stainless steel from 0.5 to 6 mm bends with slightly larger minimum radii than mild steel due to work hardening. 304 and 316L are standard; 2205 duplex requires heavier press tonnage and a bend radius of 2× thickness or more.

Aluminum from 0.5 to 8 mm bends with very small radii on softer grades (5052, 1050) and larger radii on heat-treated alloys (6061-T6, 7075-T6). Springback is higher on aluminum than on steel.

Copper, brass, and bronze bend with the smallest radii of any common material because they are highly ductile. Beryllium copper (C1720) requires age hardening after forming to reach final mechanical properties.

Specialty alloys like Inconel 625 and Hastelloy bend, but require slow press speed, frequent annealing, and tooling allowance for high springback. These are quoted per-project rather than as a standard menu item.

The minimum inside bend radius depends on material grade and thickness.

A general rule for soft and medium-hardness materials is 1× material thickness. A 1.5 mm aluminum 5052-H32 sheet bends safely down to 1.5 mm inside radius. A 1.5 mm mild steel sheet bends to 1.0 mm.

Heat-treated alloys require larger radii: 6061-T6 aluminum needs 2.5× thickness and 7075-T6 needs 3× to 4× thickness or warm forming.

Stainless 304 bends at 1× thickness across the grain and 1.5× along the grain. Stainless 316L is slightly worse at 1.2× to 1.5× across the grain.

Going below the minimum bend radius causes outer-fiber cracking, springback variation, and reduced fatigue life. Our DFM review verifies bend radius against material data before tooling is selected.

Our standard press brakes accommodate parts up to 4,000 mm bend length with table tonnages from 100 to 3,000 tons. Tandem press brake setups extend bend length to 6,000 mm for long architectural and structural components.

Press tonnage is matched to material thickness and bend length. A 3 mm mild steel sheet bent at a 1,000 mm length needs about 60 tons; a 6 mm sheet at 4,000 mm length needs over 600 tons. Our 3,000-ton press handles 12 mm structural plate at full table length.

Tube benders accommodate round tubing up to 100 mm in diameter and rectangular tubing up to 80 × 80 mm. Roll bending handles plate up to 3,000 mm in length and cylinders up to 2,000 mm diameter.

If your part exceeds these envelopes, splitting and welding the assembly is usually the right approach. Our welding cell handles the joint downstream.

Springback is the angular relaxation that happens when the press brake punch retracts. Steel typically springs back 1 to 3 degrees; aluminum 2 to 5 degrees; titanium 5 to 10 degrees.

Three methods compensate for springback:

Overbending. The press programs an angle slightly past the target, accounting for the predicted springback. Standard for mild steel and most production work.

Adaptive press brakes with laser angle measurement. The press measures bend angle during the cycle and adjusts depth in real time, holding ±0.25° regardless of material variation. Standard on tight-tolerance work.

Bottoming and coining. The press drives the punch fully into the die, plastically deforming the bend region and eliminating most springback. Used on thicker material where appearance and angle accuracy both matter.

Springback compensation is set during first-article setup and confirmed against the drawing before production begins.

Yes. Most production programs include at least one post-machining operation.

Anodizing is standard on aluminum parts for corrosion and wear resistance. Type II anodizing adds 5 to 25 μm; Type III hardcoat adds 25 to 75 μm for abrasion-heavy applications.

Powder coating is standard on steel parts for outdoor or high-salt environments. Powder coat delivers 500 to 1,000 hours of salt spray resistance in 60 to 120 μm coatings.

Passivation is required on stainless steel medical and food-grade parts to remove free iron and restore the chromium oxide layer (ASTM A967).

Hot-Dip Galvanizing and Plating adds bright chrome, nickel, zinc, or tin for cosmetic and functional finishes on steel and brass. Plating adds 5 to 30 μm to part dimensions.

Polishing to Ra 0.2 to 0.8 μm is available for optical surfaces, sealing faces, and mirror finishes. Specify on the drawing which surfaces require polishing since it is a manual operation.

Decide on finish requirements during the DFM review because they often influence material selection and dimensional tolerance.

Custom fastener production covers a range of processes that convert wire or bar stock into finished parts. Here are the primary processes available through most full-service fastener manufacturers.

1. Cold Heading: Progressive dies form the head, shank, and recesses from a wire blank. The most cost-effective process for volumes above 10,000 pieces. Diameter range 1.5 to 25 mm.

2. CNC Turning: Rotating bar stock is machined by cutting tools. Suitable for fasteners with complex geometries, unusual thread forms, or tolerances tighter than cold heading allows.

3. Swiss Machining: A variant of CNC turning for small-diameter, long, or precision parts. Used for miniature fasteners and medical screws with tolerances to ±0.01 mm.

4. Thread Rolling: Hardened dies form threads by cold displacement rather than cutting. Rolled threads are stronger than cut threads and produce no chips. Standard process for high-strength fasteners.

5. Traitement thermique : Quenching, tempering, carburizing, or induction hardening produces fasteners to specified strength grades (Grade 5, 8, Class 8.8, 10.9, 12.9).

6. Plating and Coating: Zinc, hot-dip galvanizing, electroless nickel, black oxide, Dacromet, and chrome plating applied after threading. Provides corrosion resistance and appearance.

7. Inspection and Testing: Dimensional inspection with CMM and thread gauges. Mechanical testing includes tensile, hardness, and torque-tension. Salt spray testing for plated fasteners.

A full-service manufacturer combines these processes under one roof, reducing lead times and eliminating the coordination overhead of managing multiple suppliers.