Standard:DIN6340
Description:
Regarding DIN 6340 washers, if they are specified to have a "Black Oxide" finish, it means that they have undergone a surface treatment process known as black oxide coating or blackening.
Black oxide coating is a conversion coating that creates a thin black layer on the surface of the washer. The process typically involves immersing the washers in an alkaline solution at high temperature. This coating provides several benefits, including improved corrosion resistance, increased lubricity, and enhanced aesthetic appearance.
The black oxide coating primarily serves as a protective layer against corrosion, although it may not offer the same level of corrosion resistance as some other coatings, such as hot-dip galvanizing or Dacromet. It is commonly used in applications where aesthetics or mild corrosion resistance are desired, such as decorative or low-corrosion environments.
In summary, DIN 6340 washers with a "Black Oxide" finish are heavy washers available in metric sizes ranging from M6 to M30. The black oxide coating provides some corrosion resistance while also offering an attractive black appearance. However, if high levels of corrosion resistance are required, alternative coatings or finishes may be more suitable.
| Material | 45#/40CR |
| Size | M6-M30 |
| Finish | Plain/black/ZINC/HDG/Dacromet/Mechanical Galvanized |
| Hardness | HV300/HRC35-45 |
| Marking | can be Customized |
| Application | Constrution/Wind turbines/railway line |
| Packing | Carton+ pallet; we can pack washers as your requirements |
| Terms | FOB+shanghai/ningbo |
| Delivery time | 30-70days |
| Size | Inner diameter(min) | Inner diameter(max) | Outside diameter(max) | Outside diameter(min) | Thinkness |
|---|---|---|---|---|---|
| M6 | 6.4 | 6.75 | 17 | 16.57 | 3 |
| M8 | 8.4 | 8.76 | 23 | 22.48 | 4 |
| M10 | 10.5 | 10.93 | 28 | 27.48 | 4 |
| M12 | 13 | 13.43 | 35 | 34.38 | 5 |
| M16 | 17 | 17.43 | 45 | 44.38 | 6 |
| M20 | 21 | 21.52 | 50 | 49.38 | 6 |
| M24 | 25 | 25.52 | 60 | 59.26 | 8 |
| M30 | 31 | 31.62 | 68 | 67.26 | 10 |
Products pictures for Flat washers
