Plain Washers
What are Plain Washers?
Plain washers, also known as flat washers, are thin, disk-shaped components placed between a fastener and the surface material to distribute load evenly and protect surfaces from damage. They offer a stable bearing surface and help prevent loosening by minimizing friction and wear during tightening.
Asiad Steel Industries stands as a prominent manufacturer, supplier, and exporter of Plain Washers in diverse sizes, grades, and finishes.
Key Features
Load
Distribution
Durable
Construction
Easy Installation
& Removal
Wide
Compatibility
Corrosion
Resistant
Specifications
| Specification Category | Parameter / Feature | Details / Options |
|---|---|---|
| Size Range | Nominal Size | M2 to M100 (custom sizes available) |
| Pressure Ratings | ANSI / ASME Class | Class 150, 300, 600, 900, 1500, 2500 (when used in pressure-retaining assemblies) |
| PN Ratings | PN6, PN10, PN16, PN25, PN40, PN64 | |
| Product Types | Washer Variants | Plain Washer, Large Series Washer, Narrow Series Washer |
| Standard Series | DIN 125, ISO 7089, ISO 7090 | |
| Material Options | Carbon Steel | Grades 4.6, 5.6, 8.8, 10.9 |
| Stainless Steel | A2-70, A4-70, A4-80 | |
| Standards & Certifications | ASTM | ASTM F436, ASTM F844 |
| ASME / ANSI | ASME B18.22.1 | |
| ISO / DIN | ISO 7089, ISO 7090, DIN 125, DIN 433 | |
| Certifications | ISO 9001, PED 2014/68/EU, NACE MR0175, RoHS, CE | |
| Design Features | Shape | Flat circular disc with central hole |
| Dimensional Tolerance | As per ISO 4759 / DIN / ASTM standards | |
| Thickness Range | 0.3 mm to 12 mm (standard), custom available | |
| Coating & Surface Finish | Anti-Corrosion Coating | Zinc Plated, Black Oxide, Hot Dip Galvanized |
| Optional Coatings | PTFE, Geomet, Dacromet, Phosphate | |
| Surface Finish | Polished, Self-Colored, Passivated, Oiled | |
| Testing & Inspection | Mechanical Testing | Hardness, Proof Load |
| Non-Destructive Testing | Magnetic Particle (MPI), Dye Penetrant (DPT) | |
| Dimensional Inspection | GO/NO-GO Gauges, Micrometer Verification, Thickness Measurement |
Dimensions
| Nominal Size (Bolt d) | Inner Diameter (d1) mm | Outer Diameter (d2) mm | Thickness (h) mm | Chamfer | Standard Reference |
|---|---|---|---|---|---|
| M2 | 2.2 | 5.0 | 0.3 – 0.5 | No | DIN 125A / ISO 7089 |
| M2.5 | 2.7 | 6.0 | 0.5 – 1.0 | No | DIN 125A / ISO 7089 |
| M3 | 3.2 | 7.0 | 0.5 – 1.0 | No | DIN 125A / ISO 7089 |
| M4 | 4.3 | 9.0 | 0.8 – 1.0 | No | DIN 125A / ISO 7089 |
| M5 | 5.3 | 10.0 | 1.0 – 1.5 | No | DIN 125A / ISO 7089 |
| M6 | 6.4 | 12.0 | 1.0 – 2.0 | Yes | DIN 125B / ISO 7090 |
| M8 | 8.4 | 16.0 | 1.5 – 2.5 | Yes | DIN 125B / ISO 7090 |
| M10 | 10.5 | 20.0 | 2.0 – 3.0 | Yes | DIN 125B / ISO 7090 |
| M12 | 13.0 | 24.0 | 2.5 – 3.5 | Yes | DIN 125B / ISO 7090 |
| M14 | 15.0 | 28.0 | 2.5 – 4.0 | Yes | DIN 125B / ISO 7090 |
| M16 | 17.0 | 30.0 | 3.0 – 5.0 | Yes | DIN 125B / ISO 7090 |
| M18 | 19.0 | 34.0 | 3.0 – 5.0 | Yes | DIN 125B / ISO 7090 |
| M20 | 21.0 | 37.0 | 3.0 – 6.0 | Yes | DIN 125B / ISO 7090 |
| M22 | 23.0 | 39.0 | 3.0 – 6.0 | Yes | DIN 125B / ISO 7090 |
| M24 | 25.0 | 44.0 | 4.0 – 8.0 | Yes | DIN 125B / ISO 7090 |
| M27 | 28.0 | 50.0 | 4.0 – 8.0 | Yes | DIN 125B / ISO 7090 |
| M30 | 31.0 | 56.0 | 4.0 – 10.0 | Yes | DIN 125B / ISO 7090 |
| M33 | 34.0 | 60.0 | 5.0 – 10.0 | Yes | DIN 125B / ISO 7090 |
| M36 | 37.0 | 66.0 | 5.0 – 10.0 | Yes | DIN 125B / ISO 7090 |
| M39 | 40.0 | 72.0 | 6.0 – 12.0 | Yes | DIN 125B / ISO 7090 |
| M42 | 43.0 | 78.0 | 6.0 – 12.0 | Yes | DIN 125B / ISO 7090 |
| M45 | 46.0 | 85.0 | 6.0 – 12.0 | Yes | DIN 125B / ISO 7090 |
| M48 | 50.0 | 92.0 | 6.0 – 12.0 | Yes | DIN 125B / ISO 7090 |
| M52 | 54.0 | 98.0 | 8.0 – 14.0 | Yes | DIN 125B / ISO 7090 |
| M56 | 58.0 | 105.0 | 8.0 – 14.0 | Yes | DIN 125B / ISO 7090 |
| M60 | 62.0 | 110.0 | 8.0 – 14.0 | Yes | DIN 125B / ISO 7090 |
| M64 | 66.0 | 115.0 | 8.0 – 14.0 | Yes | DIN 125B / ISO 7090 |
| M72 | 74.0 | 130.0 | 10.0 – 16.0 | Yes | DIN 125B / ISO 7090 |
| M80 | 82.0 | 140.0 | 10.0 – 18.0 | Yes | DIN 125B / ISO 7090 |
| M90 | 92.0 | 160.0 | 12.0 – 20.0 | Yes | DIN 125B / ISO 7090 |
| M100 | 102.0 | 175.0 | 12.0 – 20.0 | Yes | DIN 125B / ISO 7090 |
Mechanical Properties
| Property | Value | Unit / Standard |
|---|---|---|
| Tensile Strength | 400 – 1,200 (depends on material grade) | MPa (Carbon Steel, Stainless Steel, Alloy Steel) |
| Yield Strength | 250 – 1,000 | MPa |
| Hardness | 100 – 450 | HV / HB (Brinell / Vickers, grade-dependent) |
| Elongation | ≥ 8 – 25 | % |
| Density | 7.7 – 8.0 | g/cm³ |
| Impact Toughness | ≥ 27 – 70 | J (Charpy, material-dependent) |
| Modulus of Elasticity (E) | ~200 | GPa |
| Fatigue Strength | 150 – 400 | MPa |
| Corrosion Resistance | Good to Excellent (SS > Alloy Steel > CS) | – |
| Thermal Conductivity | 15 – 50 | W/m·K |
| Coefficient of Expansion | 10 – 17 ×10⁻⁶ | /°C |
| Yield Ratio (YS/UTS) | 0.40 – 0.70 | – |
| Poisson’s Ratio | 0.27 – 0.30 | – |
| Brinell Hardness Range | 100 – 450 | HB |
| Surface Finish | Bright, Zinc-Plated, Black Oxide, Phosphate | DIN / ISO standards |
| Manufacturing Type | Stamped, Machined, or Laser-Cut | Process-dependent |
| Operating Temperature Range | -50 to 300 (standard steels), up to 600 for heat-resistant alloys | °C |
| Pressure Application Suitability | Suitable for bolted joint load distribution, not direct pressure retention | – |
Chemical Composition
| Element | SS 304 (%) | SS 304L (%) | SS 316 (%) | SS 316L (%) |
|---|---|---|---|---|
| Chromium (Cr) | 18.0 – 20.0 | 18.0 – 20.0 | 16.0 – 18.0 | 16.0 – 18.0 |
| Nickel (Ni) | 8.0 – 10.5 | 8.0 – 12.0 | 10.0 – 14.0 | 10.0 – 14.0 |
| Carbon (C) | ≤ 0.08 | ≤ 0.03 | ≤ 0.08 | ≤ 0.03 |
| Manganese (Mn) | ≤ 2.00 | ≤ 2.00 | ≤ 2.00 | ≤ 2.00 |
| Silicon (Si) | ≤ 1.00 | ≤ 1.00 | ≤ 1.00 | ≤ 1.00 |
| Phosphorus (P) | ≤ 0.045 | ≤ 0.045 | ≤ 0.045 | ≤ 0.045 |
| Sulfur (S) | ≤ 0.030 | ≤ 0.030 | ≤ 0.030 | ≤ 0.030 |
| Iron (Fe) | Balance | Balance | Balance | Balance |
| Molybdenum (Mo) | — | — | 2.0 – 3.0 | 2.0 – 3.0 |
Applications of Plain Washers
Construction &
Infrastructure
Automotive & Heavy
Equipment
Manufacturing &
Fabrication
Medical & Laboratory
Equipment
Electrical &
Electronics Assembly
Oil, Gas & Petrochemical
Installations
Do you have questions?
What is a plain washer used for?
What is the standard size range for plain washers?
Can I use plain washers in high-vibration areas?
Do you offer customized sizes and coatings?
