Bending parts are sheet metal components shaped by applying a controlled force to a flat metal blank so that it permanently deforms along a straight axis — a process governed by the material's yield strength and work-hardening behaviour. The resulting geometry typically includes flanges, channels, brackets, enclosure panels, and frame profiles used across industrial, medical, and consumer-electronics applications.
According to Fundamentals of Modern Manufacturing (Groover, 5th ed., Wiley, 2013), press-brake bending — the dominant process for producing sheet metal bending parts — accounts for more than 30 % of all sheet-metal forming operations worldwide, owing to its flexibility in handling both short prototype runs and high-volume production without the cost of dedicated hard tooling.
At Jiafeng, bending parts are produced on Salvagnini servo-electric panel benders and Amada / domestic CNC press brakes ranging from 35 T to 250 T, all programmed offline via CAD/CAM to guarantee first-hit accuracy. Explore our complete sheet metal manufacturing capabilities or learn how bending integrates with our precision machining and mechatronics integration services.
Data sourced from in-house machine parameters and verified against DIN 6935 (Cold Bending of Flat-Rolled Steel) and EN ISO 2768-m (General Tolerances).
| Equipment | Capacity / Range | Bend Angle Accuracy | Max Sheet Thickness | Best For |
|---|---|---|---|---|
| Salvagnini Auto Bender | Up to 3,000 mm flange | ±0.2° | 3 mm (steel) | High-volume cabinet shells, chassis, box profiles |
| CNC Press Brake (250 T) | 35 T – 250 T; up to 4,000 mm | ±0.3° | 12 mm (steel); 10 mm (Al) | Heavy structural bending parts, thick-wall brackets |
| Servo Press Brake (Precision) | 35 T – 100 T | ±0.1° | 6 mm (steel) | Precision enclosure panels, medical components |
| CNC Press Brake (Multi-V) | 35 T – 160 T | ±0.3° | 8 mm (steel) | Complex multi-bend bending parts, Z/U profiles |
¹ Tolerances per DIN 6935 and EN ISO 2768-m. Tighter tolerances available on request.
Different bending methods suit different geometries, materials, and production volumes. Jiafeng engineers select the optimal technique during DFM review to minimise springback, avoid cracking, and hit your tolerances first time. The classification below follows the framework established in Sheet Metal Forming Processes and Die Design (Suchy, 2nd ed., McGraw-Hill, 2006).
| Method | Principle | Typical Bend Angle | Thickness Range | Springback Tendency | Typical Use |
|---|---|---|---|---|---|
| Air Bending (V-die) | Punch presses sheet into V-die; sheet contacts only punch tip and die shoulders | 1°–180° | 0.5–12 mm | Medium – compensated by CNC back-gauge | Most bending parts; versatile, low tooling cost |
| Bottom Bending (Coining) | Punch forces sheet fully into die; material is coined at bottom of stroke | Fixed by die angle | 0.5–6 mm | Very low (±0.1°) | High-precision bending parts requiring exact, repeatable angles |
| Panel Bending (Salvagnini) | Blank is clamped; bending blade folds flange upward and downward sequentially | Up to 300° total | 0.5–3 mm | Low (servo-controlled) | Box-form bending parts; high-volume enclosures |
| Roll Bending | Three rolls progressively curve the sheet into arcs or cylinders | Arc / full cylinder | 1–20 mm | Medium | Curved bending parts: tubes, cones, arched covers |
| Step Bending | Multiple small-increment bends approximate a curved profile | Radius-dependent | 0.5–6 mm | Low (cumulative) | Large-radius curved bending parts without a roll bender |
| Rotary Bending | Rotating die tool bends sheet without a counter-die — scratch-free | Up to 90° (overben) | 0.3–3 mm | Low | Cosmetic bending parts; pre-coated or decorated sheet |
Springback — the elastic recovery that occurs when bending load is released — is the key variable in bending-part design. It is quantified by the springback factor K = θf/θi, where θf is the final angle and θi is the loaded angle. Values are derived from published data in Manufacturing Engineering and Technology (Kalpakjian & Schmid, 7th ed., Pearson, 2014) and confirmed against Jiafeng's in-house process records.
| Material | Grade | Tensile Strength | Min Bend Radius (×t) | Springback Factor K | Jiafeng Stock Thickness |
|---|---|---|---|---|---|
| Cold-Rolled Steel | SPCC / DC01 | 270–370 MPa | 0.5 t | 0.97–0.99 | 0.5–6.0 mm |
| Stainless Steel | 304 / 316 | 485–720 MPa | 1.0 t | 0.95–0.98 | 0.5–12 mm |
| Galvanised Steel | SGCC / DX51D | 270–370 MPa | 0.5 t | 0.97–0.99 | 0.5–3.0 mm |
| Aluminium 5052 | 5052-H32 | 195–260 MPa | 1.0 t | 0.93–0.96 | 0.5–10 mm |
| Aluminium 6061 | 6061-T6 | 276–310 MPa | 1.5 t | 0.90–0.94 | 0.5–10 mm |
| Electrolytic Zinc Steel | SECC | 270–340 MPa | 0.5 t | 0.97–0.99 | 0.5–3.0 mm |
| Copper C110 | C11000 (ETP) | 220–250 MPa | 0.5 t | 0.96–0.98 | 0.5–5.0 mm |
t = material thickness. K values are indicative; final springback compensation is set by CNC back-gauge programming. Min bend radius per transverse grain direction; longitudinal direction may require 1.5× these values.
Jiafeng's bending tolerances comply with DIN 6935 (Cold Bending of Flat-Rolled Steel, 2011 revision) and EN ISO 2768-m (General Tolerances — Part 1, linear dimensions). Our precision tier exceeds these standards; contact our engineering team for GD&T-controlled drawings.
| Dimension / Feature | Standard Tolerance | Precision Tolerance | Applicable Standard | Verification Method |
|---|---|---|---|---|
| Bend Angle | ±0.5° | ±0.1° | DIN 6935 | Digital protractor / CMM |
| Flange Length | ±0.30 mm | ±0.10 mm | DIN 6935 / ISO 2768-m | CCD vision system ±50 µm |
| Overall Length / Width | ±0.20 mm | ±0.05 mm | ISO 2768-m | CMM E=(1.9+3L/1000) µm |
| Hole-to-Bend Distance | ±0.20 mm | ±0.10 mm | ISO 2768-m | CMM / optical comparator |
| Flatness (after bending) | 0.5 mm / 300 mm | 0.2 mm / 300 mm | ISO 1101 | Surface plate + dial gauge |
| Inner Bend Radius | ±0.20 mm | ±0.05 mm | DIN 6935 | Radius gauge / CMM |
| Parallelism of Flanges | 0.3 mm / 100 mm | 0.1 mm / 100 mm | ISO 1101 | CMM geometric analysis |
Sheet metal bending parts are a structural backbone across virtually every manufacturing sector. Jiafeng's vertically integrated plant produces bending parts for global customers; our mechatronics integration line can take bent sub-assemblies through to fully wired, tested finished goods.
| Industry | Typical Bending Parts | Key Requirements | Jiafeng's Advantage |
|---|---|---|---|
| Power & Energy | Switchgear panels, busbar supports, cable tray bending parts | IEC 61439; IP54+; arc-flash clearances | 128 h salt-spray zinc; co-located welding & coating |
| Medical Devices | Imaging equipment frames, surgical tray bending parts, IV stand brackets | ISO 13485; biocompatibility; ±0.05 mm dims | Passivated SS304/316; CMM 100 % FAI |
| Telecom & Data Centre | 19″ rack mounting bending parts, cable management brackets, antenna mounts | EIA 310-D hole patterns; EMI shielding | NCT punching + bending in one setup; SECC stock |
| Semiconductor | Wafer-handling frame bending parts, cleanroom panel brackets, gas-line supports | Particle control; ultra-flat surfaces; class-1 clean | Precision laser + CMM; electropolished SS |
| Industrial Automation | Robot-cell guarding, PLC cabinet bending parts, servo drive brackets | Structural rigidity; fast turnaround; modular design | Salvagnini auto-bender; 7–15 day lead time |
| EV & New Energy | Battery module frame bending parts, inverter housings, charging station shells | IP65+; thermal management; lightweight | Aluminium 5052/6061 bending; ceramic conversion + powder coat |
| Retail & Vending | Vending machine outer-panel bending parts, display door frames, POS brackets | High-gloss cosmetic finish; corrosion resistance | Dual coating lines; RAL colour matching; pad printing |
| Financial Equipment | ATM shell bending parts, cash-recycler modules, self-service kiosk frames | Tamper evidence; aesthetic compliance; tight dims | Precision punching + multi-bend; silk-screen printing |
Designing bending parts with manufacturability in mind reduces scrap, improves repeatability, and shortens lead time. The following rules are drawn from standard DFM practice (Boothroyd, Dewhurst & Knight, Product Design for Manufacture and Assembly, 3rd ed., CRC Press, 2011) and adapted to our production environment.
Keep flange length ≥ 4× material thickness to allow the back-gauge to reference accurately. Shorter flanges may require custom tooling and longer setup time.
Locate holes ≥ 2× sheet thickness + bend radius from the bend line. Holes placed too close will deform and lose dimensional accuracy during forming.
Use a single internal radius (typically 1× material thickness) throughout the part. Multiple radii require multiple V-die sets and increase setup time and cost.
Orient the bend line perpendicular to the rolling direction of the sheet. Bending parallel to grain increases cracking risk and may require a larger minimum bend radius.
Add a laser-cut slot (width ≥ 1× thickness) at each end of a bend line that terminates at a feature. This prevents material tearing and cracking at the bend termination.
The neutral-axis shift is expressed as the K-factor (typically 0.33–0.50 for air bending). Provide flat-blank dimensions or let our CAD/CAM system compute the developed length using your material's confirmed K-factor.
Every bending-parts order follows a documented workflow. Our sheet metal manufacturing and precision machining lines share one integrated quality system.
2D/3D CAD files reviewed; manufacturability feedback and blank-development calculation within 24 h.
Mill-certified blanks cut to ±0.05 mm on 3 kW–12 kW fibre lasers; burr-free edges minimise secondary processing.
Salvagnini auto-bender or CNC press brake programmed offline; springback compensation dialled in from material data.
PEM insertion, tapping, welding, deburring — all in-house. Learn more in our mechatronics integration section.
Powder coating, zinc plating (96–128 h salt spray), passivation, anodising, or silk-screen — per your spec.
First-article CMM report, 100 % outgoing visual check, dimensional certificate provided. EXW / FOB / CIF worldwide.
| Capability | Jiafeng Standard | What It Means for You |
|---|---|---|
| Bending Accuracy | ±0.1° angle; ±0.10 mm flange length (precision) | First-time fit with mating components — no rework |
| Tonnage Range | 35 T – 250 T CNC press brakes | Thin foil to 12 mm plate — one supplier for all gauges |
| Automation | Salvagnini servo-electric panel bender | High-volume bending parts with zero operator-to-operator variation |
| Lead Time | 7–15 business days standard | Faster than multi-supplier models; expedite available |
| Vertical Integration | Cutting → bending → welding → coating → QC in one factory | Single PO, single point of accountability, full traceability |
| Material Breadth | Steel, SS, Al, Cu, GI, SECC, spring steel | No need to find a specialist sub-contractor for non-standard alloys |
| Quality System | CMM + CCD vision + X-ray + ROHS + tensile tester | Full inspection data package with every shipment |
| OEM/ODM Support | In-house R&D centre + DFM review | Design-to-production: reduce your engineering overhead |
Jiafeng accepts orders from 1 piece upward. CNC laser cutting and press-brake bending require no hard tooling, so prototype bending parts are cost-effective. Volume pricing applies from 500 pieces. Our OEM/ODM team can assist with DFM before you commit to production quantities.
Standard bend-angle tolerance is ±0.5° (DIN 6935). Our precision tier achieves ±0.1° on angle and ±0.10 mm on flange length, verified by CMM (E = 1.9 + 3L/1,000 µm) or CCD vision system (±50 µm). Contact our engineering team for GD&T-controlled requirements.
We bend cold-rolled steel (SPCC/DC01), hot-rolled steel, galvanised steel (SGCC/SECC), stainless steel (SS304, SS316, SS430), aluminium alloys (5052, 6061, 6063), copper (C110), brass, and spring steel (65Mn). Thickness range is 0.3 mm–12 mm depending on material and process. See our full precision machining and materials page for additional alloys.
We accept DXF, DWG, STEP, IGES, and PDF drawings. 3D STEP files are preferred for complex bending parts as they allow our CAM software to auto-generate bend sequences and verify flat-blank development. Submit files via our contact page; an engineer will respond with a DFM report and quotation within 24 hours.
All treatments are in-house: powder coating (any RAL colour; 500–1,000 h salt spray), zinc electroplating (96–128 h; blue-white or yellow chromate), ceramic conversion coating, laser marking, silk-screen/pad printing, weld-seam polishing, and passivation. Anodising is available through vetted partners. Learn more on our sheet metal manufacturing page.
