Lorsqu'il s'agit de fabriquer des vis (des composants critiques dans tous les domaines, de l'électronique à l'aérospatiale), comment pouvez-vous vous assurer que chaque pièce respecte des dimensions strictes ?, fil, et normes de résistance? The answer lies in the CNC machining screw process—a computer-controlled workflow that turns raw metal into high-precision fasteners with unmatched consistency. Ce guide détaille l'ensemble du processus, solves common pain points, and helps you understand why CNC is the top choice for screw production.
1. What Is the CNC Machining Screw Process?
Le CNC machining screw process uses computer numerical control (CNC) technology to automate the cutting, façonner, and threading of screws. Contrairement à usinage manuel (which relies on human skill to operate tools), CNC systems follow preprogrammed instructions to produce screws with tight tolerances—often as small as ±0.001 inches.
Think of it like baking cookies with a precise recipe: the CNC program is your “recipe,” and the machine is your oven—consistently turning out perfect results every time. For screws, this consistency is non-negotiable: a poorly sized screw can ruin an electronic device or compromise a building’s structure.
2. The 8-Step CNC Machining Screw Process (Linear Workflow)
Creating a screw via CNC machining follows a clear, repeatable sequence. Skip a step, and you risk defects—so let’s walk through each stage in order:
- Design Modeling with CAD Software: D'abord, utiliser GOUJAT (Conception Assistée par Ordinateur) outils (par ex., SolidWorks, AutoCAD) to build a 3D model of the screw. This model includes every detail: thread pitch (par ex., 2mm), head shape (flat, pan, or hex), and length (par ex., 10mm). Without an accurate CAD model, the final screw won’t fit its intended use.
- Data Conversion to Machine-Readable Format: Export the CAD model to an STL or STEP file—formats CNC machines can “understand.” This step bridges the gap between design and manufacturing: if the file is corrupted, the machine will misinterpret the design.
- Programming with CAM Software: Utiliser CAME (Fabrication assistée par ordinateur) software to turn the 3D model into G-code—the language of CNC machines. The G-code tells the machine exactly how to move: tool speed (par ex., 1,500 RPM), cutting depth, and thread spacing. Par exemple, a G-code line might say, “Cut a 2mm thread for 10mm along the metal rod.”
- Raw Material Selection & Préparation: Choose the right material based on the screw’s use. Les options courantes incluent:
- Acier inoxydable: For corrosion resistance (par ex., outdoor furniture screws).
- Acier au carbone: For strength (par ex., construction screws).
- Acier allié: For high-stress applications (par ex., automotive engine screws).
Cut the raw material into rods of the correct length (par ex., 12mm for a 10mm screw, leaving extra for machining).
- Clamping & Positionnement: Secure the metal rod in the CNC machine’s chuck (a clamping device) and align it precisely. Even a 0.005-inch misalignment can make the screw’s thread uneven—so operators use laser sensors to ensure perfect positioning.
- Usinage CNC (Coupe, Threading, Façonner): The machine executes the G-code, using tools like drills (pour les trous) and taps (for threading) to shape the screw. This stage may include:
- Tournant: Spinning the rod while a tool cuts the head shape.
- Fraisage: Carving grooves or slots (par ex., une tête Phillips).
- Threading: Using a tap to cut spiral threads into the rod.
A single CNC machine can produce 500+ screws per hour—10x faster than usinage manuel.
- Contrôle qualité: Test every batch of screws for key metrics:
- Précision dimensionnelle (par ex., is the diameter exactly 5mm?).
- Thread accuracy (par ex., does it fit a standard nut?).
- Surface quality (no burrs or scratches).
Inspectors use calipers and thread gauges—if even 1% of screws fail, the batch is reworked.
- Post-Treatment & Finition: Improve the screw’s durability with post-processing:
- Ébavurage: Removing sharp edges (prevents hand injuries during installation).
- Traitement thermique: Heating and cooling to strengthen the metal (par ex., for high-stress screws).
- Placage: Adding a layer of zinc or chrome for corrosion resistance (par ex., bathroom screws).
- Packing & Warehousing: Package 合格 screws in boxes (par ex., 100 screws per box) and store them in a dry warehouse to avoid rust. Ready for shipment to manufacturers or retailers.
3. Usinage CNC vs. Traditional Manual Machining for Screws
Why choose CNC over manual machining for screw production? Let’s compare the two methods with hard data:
| Facteur | Processus de vis d'usinage CNC | Traditional Manual Machining |
| Précision | Tolerances of ±0.001–±0.005 inches | Tolerances of ±0.01–±0.05 inches (dépend de la compétence de l'opérateur) |
| Production Speed | 500–1,000 screws per hour | 50–100 screws per hour |
| Cohérence | 99.9% of screws meet standards | 80–90% consistency (varies by operator) |
| Labor Cost | 1 operator monitors 3–5 machines | 1 operator per machine |
| Idéal pour | High-volume runs (1,000+ vis) or precision parts | Petits lots (100–500 screws) or simple designs |
4. 3 Common Problems in CNC Machining Screw Process (and How to Fix Them)
Even with CNC’s precision, issues can arise. Here are the top pain points and solutions:
| Problème | Cause | Solution |
| Uneven Threads | Misaligned raw material or dull threading tool | Use laser alignment tools and replace taps every 5,000 vis. |
| Screw Head Cracks | Too much pressure during turning or low-quality material | Reduce tool pressure by 10% and use certified alloy steel (par ex., ASTM A325). |
| Rust After Production | Humidity during post-treatment or poor plating | Dry screws in a 60°C oven for 30 minutes and use a 2-layer zinc plating. |
5. Yigu Technology’s Perspective on CNC Machining Screw Process
Chez Yigu Technologie, we’ve optimized the CNC machining screw process pour 100+ clients—from electronics makers to aerospace companies. The biggest issue we solve? Custom screw production. Many clients need non-standard screws (par ex., a 3mm thread with a custom hex head), and our CAD/CAM team can turn their design into a production-ready program in 24 heures.
We also use AI-powered inspection tools to cut defect rates to 0.5%—half the industry average. Par exemple, a medical device client now produces 10,000 precision screws monthly with our process, meeting FDA standards with zero rejections. As CNC tech advances, we’ll keep making the process faster and more affordable for small-batch orders.
FAQ: Your Top CNC Machining Screw Process Questions Answered
Q1: How long does it take to set up the CNC machining screw process for a new screw design?
A1: For a standard design (par ex., a 5mm pan-head screw), setup takes 4–6 hours (Modélisation CAO + G-code programming). Pour des conceptions personnalisées (par ex., unique thread patterns), it may take 1–2 days—but this is still 5x faster than manual machining setup.
Q2: Can the CNC machining screw process handle small batch orders (par ex., 50 vis)?
A2: Oui! CNC’s low setup cost makes it ideal for small batches. Contrairement au moulage par injection (ce qui nécessite des moules coûteux), CNC can switch between designs in hours—so 50 screws cost only slightly more per unit than 5,000.
Q3: What’s the most durable material for CNC-machined screws?
A3: It depends on the use. For outdoor or wet environments, acier inoxydable 316 is best (resists saltwater corrosion). For high-stress applications (par ex., moteurs), acier allié 4140 (traité thermiquement) offers the highest strength—can withstand up to 120,000 psi of pressure.