A metric fastener size chart helps procurement and engineering teams speak the same language. It reduces wrong RFQs, wrong thread matching, and last-minute assembly problems.
In metric fasteners, size is usually written as M + nominal diameter × pitch × length. For example, M12 × 1.75 × 80 means a 12 mm nominal diameter, 1.75 mm thread pitch, and 80 mm length.
For buyers, the key is not only the “M size.” Pitch, length, grade, coating, and matching nuts or washers must also be confirmed.
Basic Metric Fastener Size Chart
Common Metric Sizes and Coarse Pitches
| Taille métrique | Pas grossier commun | Typical Industrial Use |
|---|---|---|
| M4 | 0.7 mm | Small covers, light brackets |
| M5 | 0.8 mm | Electronics, light machinery |
| M6 | 1.0 mm | Panels, brackets, general assembly |
| M8 | 1.25 mm | Equipment frames, supports |
| M10 | 1.5 mm | Machinery, construction hardware |
| M12 | 1.75 mm | Steel frames, base plates |
| M16 | 2.0 mm | Heavy equipment, structural joints |
| M20 | 2.5 mm | Large machinery, anchors |
| M24 | 3.0 mm | Heavy-duty structures and foundations |
This chart is a starting point. Final selection should follow the drawing, project standard, or equipment manual.
For common catalog items, review attaches standards and confirm whether the product follows DIN, ISO, ASTM, or a project drawing.
What Procurement Teams Should Confirm
La taille seule ne suffit pas
A purchase request that says “M12 bolt” is incomplete. It can still lead to the wrong product.
Confirmez :
- Product type: bolt, screw, nut, washer, stud, or anchor
- Diamètre et longueur
- Thread pitch: coarse or fine
- Thread length: full thread or partial thread
- Grade: 4.8, 8.8, 10.9, 12.9, A2-70, etc.
- Surface finish: plain, zinc, HDG, zinc flake, black, stainless
- Écrous et rondelles assortis
For bolt sourcing, review produits de boulons. Pour la correspondance des rondelles, vérifiez produits de laveuse.
Engineering Checks Before Approval
Match the Size to the Application
Engineering teams should consider load, vibration, corrosion, installation space, and maintenance frequency.
For load-bearing assemblies, attaches à haute résistance may be required. For outdoor, marine, or humid environments, compare diverses attaches enduites or stainless options.
If the part has special head shape, long thread, shoulder diameter, or non-standard length, use fixations non standard sur mesure and provide a drawing.
Conseil final
A metric fastener size chart is useful, but it should not replace a complete specification. Good purchasing data includes size, pitch, length, standard, grade, coating, matching parts, and application condition.
Pour un approvisionnement plus large, consultez l'intégralité produits de fixation range before finalizing the RFQ.