板金スタンピング: 工程, 公差 & 设计 Guide

重要ポイント

• スタンピング is the fastest way to produce flat and formed 板金 parts at scale — cycle times as low as 1 second per part with progressive dies, making it the go-to process for brackets, clips, shields, and enclosures above 5,000 units.
• 工程 choice depends on part geometry and volume — blanking and piercing for flat parts, 曲げ加工 for simple forms, progressive die for complex multi-feature parts, deep drawing for hollow shells.
• Standard スタンピング 公差 are ±0.13 mm (0.005″) for hole diameters, ±0.25 mm (0.010″) for edge-to-hole positions — tighter than laser-cut-only parts because the die controls dimensions repeatably.
• Die cost dominates at low volume — a simple single-stage die costs $800–$3,000; a progressive die with 8–12 stations runs $8,000–$25,000. Below 1,000 units, レーザー切断 + CNC 曲げ加工 is usually cheaper.
• Burr direction is a critical DFM detail — stamped edges always have a burr on one side. Specify burr direction on the drawing to avoid assembly interference.
• 材料 choice affects both tool life and part cost — mild steel (SPCC) is the most stampable; stainless and high-strength steels accelerate die wear and need more frequent tool maintenance.

板金プレス加工とは？

板金 スタンピング is a cold-forming process that uses a punch and die set in a 機械的 or hydraulic press to cut, bend, or draw flat 板金 into finished parts. Unlike 出荷前に問題を発見します。 which removes material, or レーザー切断 which only cuts profiles, スタンピング simultaneously cuts and forms — producing complete parts with holes, bends, tabs, and embossed features in a single press stroke or a sequence of progressive stations.

The process is ideal for parts that are flat or shallow-formed, produced in quantities above 1,000–5,000 units, and require consistent dimensions across a long production run. Common stamped parts include mounting brackets, electrical contacts, spring clips, EMI shields, automotive body panels, and appliance housings.

In the world of custom 繰り返し注文の一貫性が保たれます。, スタンピング fills the gap between low-volume laser-cut prototyping and high-volume dedicated production. A fabricator with in-house スタンピング capability can offer you both prototype flexibility and production economics without switching suppliers mid-project.

板金プレス加工の4つの主要タイプ

最適な用途: Blanking when you need flat parts with precise hole patterns. Progressive die when part count exceeds 10,000 and the part has 3+ features. Deep drawing when you need hollow cylindrical or box-shaped parts.
Avoid when: Progressive die below 5,000 units — die amortization per part makes unit cost higher than laser + bend. Deep drawing for materials with low elongation (some アルミニウム合金s crack at draw ratios above 1.8).

プレス加工の公差：現実的な期待値

公差 in スタンピング are driven by the die, not the operator — which means they are inherently more repeatable than manually positioned レーザー切断 or press brake 曲げ加工. However, they vary significantly by feature type:

When your part has features that must locate relative to each other within a tight tolerance, specify GD&T datum references on the drawing rather than linear ± dimensions. This tells the die designer which features to use as the primary locating surfaces and which 公差 can stack.

最適な用途: Using standard 公差 for all non-critical features — tighter 公差 increase die cost by 20–40%. Reserve precision 公差 for hole patterns that locate mating components, connector cutouts, and press-fit features.
Avoid when: Specifying ±0.05 mm on overall length of a 300 mm part — thermal expansion alone can shift dimensions by 0.03 mm per 10°C temperature change.

プレス部品の材料選定

最適な用途: SPCC steel for 90% of general スタンピング work — it is the most forgiving, least expensive, and longest tool-life material. 5052 aluminum when weight matters. Spring steel only when the part must function as a spring.
Avoid when: Specifying 316 stainless for a simple indoor bracket — the material premium and accelerated die wear add cost with no functional benefit over 304.

プレス部品のDFMルール

Good スタンピング DFM reduces die cost, extends tool life, and improves part consistency. These six rules apply to nearly every stamped part:

1. Hole diameter must be at least 1× 板厚. Punching a hole smaller than the 板厚 causes punch deflection and premature breakage. For a 1.5 mm steel sheet, the smallest hole is 1.5 mm diameter.
2. Space holes at least 2× 板厚 from each other and from the part edge. Closer spacing causes the web between holes to distort or tear during punching. For 1.0 mm stock, keep holes at least 2.0 mm apart.
3. Inside bend radii should be at least 1× 板厚. Tighter radii risk cracking on the outside of the bend, especially with aluminum and stainless. For 5052 aluminum, use 1.5× 板厚 as the minimum.
4. Keep features at least 3× 板厚 from bend lines. Holes, slots, and tabs too close to a bend will distort as the material stretches. For a 1.2 mm part, keep features 3.6 mm from any bend.
5. Specify burr direction on the drawing. Every punched edge has a burr on the die side and a clean shear on the punch side. Use an arrow or note (“burr this side”) — this costs nothing but prevents assembly problems.
6. Use full-radius corners (not sharp) on blanked profiles. Sharp internal corners concentrate stress and accelerate die wear. Minimum corner radius = 0.5× 板厚 for steel, 1× for aluminum.

プレス加工 vs レーザー切断＋CNC曲げ：切り替えのタイミング

One of the most common questions from buyers is when to move from laser-cut prototypes to スタンピング production. The decision comes down to volume, part complexity, and tolerance requirements:

The crossover point where スタンピング becomes cheaper than レーザー切断 typically falls between 2,000 and 5,000 units, depending on part size and complexity. Below this volume, a good 繰り返し注文の一貫性が保たれます。 shop can produce parts economically with レーザー切断 and CNC 曲げ加工 — and you avoid the upfront die investment.

まとめ

板金 スタンピング rewards volume and punishes low quantities with tooling amortization. The key to a successful スタンピング project is matching the process to your part: blanking for simple flat parts, progressive die for complex high-volume components, deep drawing for hollow shells. Start with laser-cut prototypes to validate fit and function. Once your design is stable and volumes justify it, transition to スタンピング for the best combination of unit cost, speed, and part-to-part consistency.