Standard:USS
Description:
USS washers, also known as plain washers, are commonly used in the United States and are specified by the Unified Screw Thread Standard (USS). They are used to distribute the load and provide a larger bearing surface when used with bolts or screws. The size range you mentioned, 1/4" to 3", refers to the nominal diameter of the bolt or screw they are designed to work with.
When it comes to surface finishes for USS washers, two common options are zinc plated and hot-dip galvanized (HDG). Let's explore each of these finishes:
1.Zinc plated: Zinc plating is a common finish for washers. It involves applying a thin layer of zinc to the surface of the washer through an electroplating process. Zinc plating provides moderate corrosion resistance and helps protect the washer from rusting. It is commonly used in indoor or dry environments where exposure to moisture or corrosive elements is limited. However, over time, zinc-plated washers may corrode if subjected to harsh conditions or prolonged exposure to moisture.
2.Hot-dip galvanized (HDG): Hot-dip galvanizing is a process where the washer is immersed in molten zinc, creating a thick, durable coating. HDG provides excellent corrosion resistance and is suitable for outdoor or highly corrosive environments. The thick layer of zinc coating acts as a barrier, protecting the washer from rust and corrosion. HDG washers are commonly used in applications where long-term corrosion protection is required, such as construction, infrastructure, and marine environments.
The choice between zinc plated and hot-dip galvanized finishes for USS washers depends on the specific application requirements, considering factors such as the operating environment and the desired level of corrosion protection. Zinc-plated washers are typically suitable for indoor or less demanding environments, while hot-dip galvanized washers are preferred for outdoor or highly corrosive environments.
| 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
