Standard:USS
Description:
USS washers, also known as heavy washers, are designed to provide a larger bearing surface and distribute the load when used with bolts or screws. They adhere to the Unified Thread Standard (USS) and are commonly used in various applications. The size range you mentioned, 1/4" to 3", indicates the diameter of the bolt or screw they are designed to work with.
When specified with a "Black Oxide" finish, USS washers have undergone a surface treatment process known as black oxide coating. Black oxide coating, also known as blackening, is a conversion coating that creates a thin layer of black oxide on the surface of the washer.
The black oxide coating serves multiple purposes. First, it provides a degree of corrosion resistance, although its level of protection may not be as high as that of other coatings like hot-dip galvanizing or Dacromet. Second, the black oxide finish enhances the aesthetics of the washers, giving them a sleek black appearance. Lastly, the black oxide layer can improve the wear resistance and lubricity of the washers, facilitating smooth assembly and operation.
USS washers with a black oxide finish are commonly used in various industries where both functionality and visual appeal are important. They find applications in automotive, construction, machinery, and more. However, it's essential to consider the specific requirements of your application, including environmental conditions and load requirements, to ensure that the black oxide finish meets your needs.
Please note that while black oxide coating provides some corrosion resistance, it may not offer the same level of protection as other specialized coatings. If high levels of corrosion resistance are required, alternative coatings or finishes, such as hot-dip galvanizing or HDG, may be more suitable.
| Material | 45#/40CR |
| Size | 1/4"-3" |
| 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 diamater (max) |
Inner diamater (min) |
Outside diamater (max) |
Outside diamater (min) |
Thickness (max) |
Thickness (min) |
| 3/16“ |
14.66 |
14.15 | 6.73 | 6.22 | 1.65 | 0.91 |
| 1/4” | 19.02 | 18.47 | 8.31 | 7.8 | 2.03 | 1.3 |
| 5/16“ | 22.99 | 22.05 | 9.91 | 9.4 | 2.64 | 1.63 |
| 3/8” | 26.16 | 25.22 | 11.51 | 11 | 2.64 | 1.63 |
| 7/16“ | 32.51 | 31.57 | 13.08 | 12.57 | 2.64 | 1.63 |
| 1/2” | 35.69 | 34.57 | 14.66 | 14.15 | 3.35 | 2.18 |
| 9/16“ | 38.07 | 37.13 | 16.25 | 15.75 | 3.35 | 2.18 |
| 5/8” | 45.21 | 44.27 | 18.24 | 17.3 | 4.06 | 2.74 |
| 3/4“ | 51.56 | 50.62 | 21.39 | 20.45 | 4.5 | 3.1 |
| 7/8” | 57.91 | 56.97 | 24.58 | 23.65 | 4.88 | 3.45 |
| 1“ | 64.26 | 63.32 | 27.74 | 26.8 | 4.88 | 3.45 |
| 1-1/8” | 70.61 | 69.67 | 32.51 | 31.57 | 4.88 | 3.45 |
| 1-1/4“ | 76.96 | 76.02 | 35.69 | 34.75 | 4.88 | 3.45 |
| 1-3/8" | 83.69 | 82.3 | 39.24 | 37.85 | 5.41 | 3.45 |
| 1-1/2" | 90.04 | 88.65 | 42.42 | 41.02 | 5.41 | 3.45 |
| 1-5/8" | 96.39 | 95 | 45.59 | 44.2 | 5.41 | 3.89 |
| 1-3/4" | 102.74 | 101.35 | 48.77 | 47.37 | 5.41 | 3.89 |
| 1-7/8" | 109.09 | 107.7 | 51.94 | 50.55 | 5.41 | 3.89 |
| 2" |
115.44 |
114.05 | 55.12 | 53.72 | 5.41 | 3.89 |
| 2-1/4" | 121.79 | 120.4 | 61.47 | 60.07 | 6.3 | 4.9 |
| 2-1/2" | 128.14 | 126.75 | 67.82 | 66.42 | 7.11 | 5.33 |
| 2-3/4" | 135 | 133.1 | 74.68 | 72.77 | 7.87 | 5.79 |
| 3" | 141.35 | 139.45 | 81.03 | 79.12 | 8.31 | 6.32 |
Products pictures for Flat washers
