What a Shrapnel Stamping Part Actually Does in Your Assembly Shrapnel (also called contact spring or spring clip) is a thin metal stamping that provides electrical contact, mechanical retention, or g
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What a Shrapnel Stamping Part Actually Does in Your Assembly Shrapnel (also called contact spring or spring clip) is a thin metal stamping that provides electrical contact, mechanical retention, or g
Shrapnel (also called contact spring or spring clip) is a thin metal stamping that provides electrical contact, mechanical retention, or grounding force in connectors, switches, battery holders, and automotive relays. We manufacture these in Dongguan with a dimensional tolerance of ±0.01 mm on critical features, flatness within 0.05 mm, and surface finish down to Ra 0.8 µm. You get parts that hold consistent contact force across 10,000 insertion cycles, and we ship standard tooling samples in 7 days.
Most shrapnel failures come from unpredictable springback after forming. Our press operators use a three-step compensation method: first, we simulate bend angles in CAD; second, we run a trial strip on a 110-ton high-speed press; third, we adjust the die radius by 0.02 mm increments until the released angle matches your print. For beryllium copper and stainless steel 301, we use coining dies that reduce springback variation to ±0.5 degrees across a 10,000-piece batch.
All stamping happens in our 6,500 m² Dongguan factory on 25 presses ranging from 25 to 250 tons. We run progressive dies at 400 strokes per minute for simple shrapnel, and compound dies for parts with tight co-planarity requirements. Every die is built in-house, so we can modify a feature within 48 hours without waiting for an overseas tool shop.
Shrapnel needs both elasticity and wear resistance. We stock four primary materials: C5210 phosphor bronze (hardness 180–220 HV), C17200 beryllium copper (heat-treated to 36–42 HRC), SUS301 stainless steel (full-hard, 420–480 HV), and 65Mn spring steel (oil-quenched to 44–48 HRC). For high-cycle applications, we apply a selective heat treatment using induction hardening only on the contact nose, keeping the base spring section ductile.
If your shrapnel carries electrical current, we add a pre-plating step: nickel underplate 1–3 µm, then gold flash 0.1–0.3 µm on the contact area. This prevents galvanic corrosion and keeps contact resistance below 20 mΩ at 100 gf force. We have also run silver-plated shrapnel for high-frequency RF grounding, with plating thickness verified by X-ray fluorescence on every lot.
| Parameter | Value Range |
|---|---|
| Material thickness | 0.08 – 2.5 mm |
| Part size (L×W) | 3 × 2 mm to 120 × 80 mm |
| Hardness (after heat treat) | 36 – 48 HRC (depending on alloy) |
| Dimensional tolerance | ±0.01 mm on critical, ±0.05 mm general |
| Flatness | 0.05 mm over 25 mm length |
| Surface finish Ra | 0.8 µm (standard), 0.4 µm (lapping) |
| Contact force at 0.3 mm deflection | 50 – 300 gf (per design) |
| Burr height | ≤ 0.03 mm, deburred on request |
| Lead time (samples) | 7 days for standard tooling |
| MOQ | No MOQ – start with 100 pcs |
Shrapnel is a functional part, so we do not rely only on calipers. Every batch goes through a 100% contact force check using a digital push-pull gauge mounted on a test fixture that mimics your mating connector. We also measure part height on a CMM with 0.5 µm resolution, and we verify plating thickness on three parts per lot using XRF. For high-volume orders, we use a vision system that checks bend angle and surface scratches at 200 parts per minute, rejecting anything outside your print limits.
We provide a full inspection report with each shipment, including material mill certificates, hardness test results, and a force-displacement curve graph. If you need PPAP level 3 documentation, we prepare it cost-free for the first order from our China Dongguan hardware stamping parts manufacturer facility. This is precision manufacturing with traceability — every part can be traced to the coil lot and the press operator.
If your shrapnel is thinner than 1.5 mm and you need more than 5,000 pieces per year, stamping is always cheaper than CNC machining. A progressive die produces one shrapnel every 0.15 seconds, while CNC milling takes 40–60 seconds per part. The tooling cost (typically $800–$3,000) pays back within the first 20,000 parts. But for extremely complex 3D shapes or prototypes under 200 pieces, we recommend CNC — we do both in the same factory, so you get an honest comparison.
For material selection and cutting strategies, see our CNC cutting tool selection guide if you are also machining a mating component. And before you finalize your print, review the CNC machining tolerances guide to avoid specifying tighter limits than the stamping process can hold at low cost.
No MOQ — we accept 100 pieces for sampling and 1,000 pieces for production, made in China with full quality documentation.
Yes, we adjust the bend angle, material thickness, or heat treatment cycle to hit your exact force target, and we verify it on a test fixture before shipping.
We use in-die sensors that check part presence and height every stroke, plus a final 100% vision inspection for dimensional and surface defects.
Standard progressive die tooling takes 15–20 working days, and we ship first articles within 7 days of die approval.
We do not charge for quoting, and we do not inflate prices for small quantities. Send your 2D drawing (PDF or DXF) or 3D model (STEP) to sc@bquq.com — our engineers will review formability, contact force, and material options within 4 hours. You will receive a firm quote with tooling cost, unit price, and lead time within 12 hours. For urgent questions, message us on WhatsApp at +86 13713157787. We are a China Dongguan hardware stamping parts manufacturer shrapnel specialist, and we are ready to run your part this week.
| Parameter | Capability |
|---|---|
| Materials | SPCC, SGCC, SUS301/304/316, brass, copper, beryllium copper, phosphor bronze |
| Process | Progressive die stamping, fine blanking, deep drawing, bending, tapping |
| Tolerance | ±0.01mm standard, ±0.005mm on request |
| Surface | Zinc plating, nickel, tin, gold, powder coating, passivation, anodizing |
| Die Size | Up to 1200 x 800 mm, 16-250 ton presses |
| Thickness | 0.05 - 6.0 mm sheet metal, wire 0.1 - 8.0 mm |
| Prototype | 7-15 days tooling, no MOQ on samples |
| Inspection | Full report per batch, CMM and optical measurement |
