Product Specifications
| Model / Specification | Φ1 - Φ48 |
| Material | Carbon Steel |
| Spec. | Φ1 | Φ1.2 | Φ1.4 | Φ1.6 | Φ2 | Φ2.5 | Φ3 | Φ4 | Φ5 | Φ6 | Φ8 | Φ10 | |
| d | Max. | 1.22 | 1.42 | 1.62 | 1.82 | 2.32 | 2.82 | 3..36 | 4.36 | 5.46 | 6.6 | 8.6 | 10.74 |
| Min. | 1.1 | 1.3 | 1.5 | 1.7 | 2.2 | 2.7 | 3.2 | 4.2 | 5.3 | 6.4 | 8.4 | 10.5 | |
| dc | Max. | 3 | 3.2 | 3.5 | 4 | 5 | 6.5 | 7 | 9 | 10 | 12.5 | 17 | 21 |
| Min. | 2.75 | 2.9 | 3.2 | 3.7 | 4.7 | 6.14 | 6.64 | 8.64 | 9.64 | 12.07 | 16.57 | 20.48 | |
| h | 0.3 | 0.3 | 0.3 | 0.3 | 0.3 | 0.5 | 0.5 | 0.8 | 0.8 | 1.5 | 1.5 | 2 | |
| Wt./1,000 pcs (steel) | Type A washer | 0.0014 | 0.0016 | 0.018 | 0.024 | 0.037 | 0.108 | 0.12 | 0.308 | 0.354 | 1.066 | 2.021 | 4.078 |
| Spec. | Φ12 | (Φ14) | Φ16 | (Φ18) | Φ20 | (Φ22) | Φ24 | (Φ27) | Φ30 | Φ36 | Φ42 | Φ48 | |
| d | Max. | 13.24 | 15.24 | 17.24 | 19.28 | 21.28 | 23.28 | 25.28 | 28.28 | 31.34 | 37.34 | 43.34 | 50.34 |
| Min. | 13 | 15 | 17 | 19 | 21 | 23 | 25 | 28 | 31 | 37 | 43 | 50 | |
| dc | Max. | 24 | 28 | 30 | 34 | 37 | 39 | 44 | 50 | 56 | 66 | 78 | 92 |
| Min. | 23.48 | 27.48 | 29.48 | 33.38 | 36.38 | 38.38 | 43.38 | 49.38 | 55.26 | 65.26 | 77.26 | 91.13 | |
| h | 2 | 2 | 3 | 3 | 3 | 3 | 4 | 4 | 4 | 5 | 7 | 8 | |
| Wt./1,000 pcs (steel) | Type A washer | 5.018 | 6.892 | 11.3 | 14.7 | 17.16 | 18.42 | 32.33 | 42.32 | 53.64 | 92.07 | 182.8 | 294.1 |
Flat Washer — Product Introduction
A flat washer is an annular metal piece placed between the head of a bolt, nut or screw and the connected part. It has a through hole in the center and a circular outer edge. Its main functions are to increase the contact area, distribute pressure and protect the surface of the connected part.
Under the GB 97-1976 standard system, flat washers are divided by structure into Type A (standard series) and Type B (large series). Nominal specifications cover Φ1–Φ48 mm, and common materials include carbon steel and stainless steel.
1. Product Features
• Distinction between Type A and Type B series: Type A is the standard series with moderate outer diameter and thickness; Type B is the large series with a larger outer diameter and greater bearing area, suitable for soft materials or slotted holes.
• Specification coverage from Φ1 to Φ48: dozens of nominal specifications from Φ1 to Φ48, with clear standard values for inner diameter, outer diameter and thickness.
• Diverse material options: commonly carbon steel (such as Q235, 45# steel) and stainless steel (304, 316/A4); carbon steel parts can be blackened, zinc plated, nickel plated, etc.
• Hardness grades: common hardness grades for carbon steel flat washers are 100 HV, 200 HV and 300 HV, with different grades corresponding to different strength requirements.
• Simple structure: an annular thin sheet as a whole, with no complex structure, easy to manufacture and low in cost.
2. Product Advantages
• Distributes pressure and protects surfaces: increases the contact area between the bolt head or nut and the workpiece, reduces pressure per unit area, prevents soft materials or thin sheets from being crushed, and reduces scratches on painted and machined surfaces.
• Complete specification system: continuous specification coverage from Φ1 to Φ48, facilitating design selection and engineering procurement.
• Flexible matching of material and hardness: the carbon steel version is economical and practical, while the stainless steel version is suitable for humid or corrosive environments; different hardness grades can match bolt connections of different strengths.
• Strong versatility: as a standard part, it has uniform dimensions and can be freely combined with various bolts, screws and nuts, with good interchangeability.
3. Scope of Application
• Mechanical equipment: bolted connections in machine tools, pumps and valves, reducers, automation equipment, etc.
• Automobiles and motorcycles: fastening connections in engines, chassis, bodies, interior parts, etc.
• Electronics and home appliances: assembly of chassis, cabinets, small appliances, instruments and meters, etc.
• Construction and steel structures: steel structure connections, curtain walls, pipe flanges and other applications requiring pressure distribution.
• General industry and maintenance: furniture, shelves, metal components and daily maintenance assembly.
