Where Our Washers Work
The same washer performs very differently from a coastal jetty to a clean-in-place dairy line. The right part is a match of three things — grade, finish and standard — to the environment it lives in. Here is how we specify stainless washers for the industries we ship to most.
Grade, finish and standard — matched to the job.
Before recommending a part, we look at the chemistry of the environment, the mechanical duty of the joint, and the standard the assembly is built to. Those three choices decide everything else.
Grade — 304 or 316
304 / A2 covers most indoor, structural and general-purpose duty. 316 / 316L / A4 adds molybdenum for chlorides, acids and sea spray. The environment, not the price, drives the choice.
Finish — for the surface
One finish: plain stainless, tumble-polished in sawdust. In demanding environments the right grade — 304 versus 316/316L — sets the corrosion life; we do not plate, coat or passivate.
Standard — for the fit
DIN 125 / 433 / 9021 / 436 or ASME B18.21.1 / USS / SAE, metric or imperial, with the matching tolerance class. Tell us the standard and we build to it.
Sea spray, immersion and constant chloride attack.
Deck hardware, jetties, davits, rigging, boat-builders and offshore structures live in the most aggressive corrosion environment a washer will see. Standard 304 will surface-rust and pit here; molybdenum-bearing 316 / 316L is the baseline for the longest service life in splash and tidal zones.
Typical standards, DIN 125, DIN 9021 (fender), ASME B18.21.1
- Why stainless: 316/316L resists chloride-induced pitting and crevice corrosion far better than 304.
- Fender (DIN 9021) washers spread load on soft or oversized holes in hull and deck fittings.
- We verify the grade with our own handheld XRF spectrometer (PMI) and can include the reading with your order.
Acids, alkalis and process media on plant and piping.
Process plants, refineries, tank farms and dosing skids expose fasteners to aggressive media, washdown and elevated temperatures. 316 / 316L is the working grade; the low-carbon 316L is preferred where welding is nearby or where intergranular attack is a concern. Grade is matched to the specific media in play.
Typical standards, DIN 125, DIN 433, ASME B18.21.1
- Why stainless: molybdenum in 316 markedly improves resistance to sulphuric and other process acids.
- 316L (low carbon) minimizes carbide precipitation in welded or heat-affected assemblies.
- We verify the grade with our own handheld XRF spectrometer (PMI) and can include the reading with your order.
Outdoor renewables built to last decades unattended.
PV mounting rails, ground-mount and rooftop clamps, and wind-turbine ancillary hardware are installed once and expected to hold for 25 years or more with little maintenance. 304 is specified for most inland installations; coastal and high-humidity sites step up to 316 to defend against airborne chloride and condensation.
Typical standards, DIN 125, DIN 9021, DIN 433
- Why stainless: no maintenance painting, no galvanic sacrifice — corrosion life matches the array.
- Large-OD (DIN 9021) washers spread clamp load on thin module frames and mounting rails.
- Coastal arrays: specify 316 to resist marine-aerosol chloride attack.
Vibration-rated joints under dynamic load.
Rolling stock, chassis, exhaust and body assemblies cycle through vibration and shock. Flat and large-OD washers spread clamp load and protect thin or painted surfaces under the bolt head. 304 covers most underbody and interior fastening, with 316 reserved for exhaust-adjacent or de-iced, salt-exposed positions. We do not make spring or tooth lock washers.
Typical standards, DIN 125, DIN 9021, DIN 433
- Why stainless: resists road-salt corrosion that consumes plain-steel washers over a vehicle's life.
- Large-OD (DIN 9021) washers spread load on thin body panels and slotted brackets.
- Small-OD (DIN 433) washers fit under socket-head screws where space is tight.
Cladding and structural fastening exposed to weather.
Curtain wall, rainscreen cladding, balustrades, canopies and structural steel connections sit in the open for the life of the building. 304 is the architectural default; 316 is specified for coastal buildings, swimming-pool environments, polluted urban air, or any visible fastener where staining cannot be tolerated. Square-hole washers suit strut and channel connections, and DIN 436 square washers suit timber.
Typical standards, DIN 125, DIN 9021 (fender), square-hole / DIN 436, ASME B18.21.1
- Why stainless: no maintenance repainting and no rust-staining of finished surfaces over the building life.
- Fender (DIN 9021) washers spread load over slotted holes and soft cladding panels.
- Square-hole washers hold carriage bolts in strut and channel; DIN 436 square washers suit timber connections.
Wash-down, food-contact and cleanable surfaces.
Dairy, brewing, beverage, processing and packaging lines demand hygienic, cleanable fasteners that withstand caustic clean-in-place cycles and frequent washdown. 304 is suitable for most food-contact and general hygienic duty; 316 is preferred for high-salt, acidic or chloride-sanitizer environments. The smooth, tumble-polished stainless surface is easy to clean.
Typical standards, DIN 125, DIN 433, ASME B18.21.1
- Why stainless: non-reactive, cleanable and corrosion-resistant under caustic and acidic CIP cycles.
- 316 for brines, chlorinated sanitizers and acidic products where 304 would pit.
- The sawdust tumble-polished surface is smooth and clean, with no coating to flake off.
Industry, grade and washer type.
A quick reference for matching the right stainless grade and washer style to each environment. We confirm the final specification against your drawing and operating conditions.
| Industry | Recommended grade | Typical washer types | Typical standards |
|---|---|---|---|
| Marine & Offshore | 316 / 316L | Flat, fender | DIN 125, DIN 9021, ASME B18.21.1 |
| Chemical & Petrochemical | 316 / 316L | Flat, thin (DIN 433) | DIN 125, DIN 433, ASME B18.21.1 |
| Solar PV & Wind | 304 (inland), 316 (coastal) | Flat, fender | DIN 125, DIN 9021, DIN 433 |
| Automotive & Rail | 304 (316 salt-exposed) | Flat, fender, small-OD | DIN 125, DIN 9021, DIN 433 |
| Construction & Façade | 304, 316 (coastal / visible) | Flat, fender, square-hole | DIN 125, DIN 9021, ASME B18.21.1 |
| Food, Beverage & Hygiene | 304, 316 (brine / acid) | Flat, thin (DIN 433) | DIN 125, DIN 433, ASME B18.21.1 |
Tell us your application.
Describe the environment — the media, the load, the standard you build to — and we will recommend the grade, finish and standard that fit, then quote it. No account needed.
Tell us what you need.
Send specs or a drawing and we will come back with pricing, lead time and material options. No account needed.
- ✓ 304 / 316 / 316L, DIN & ASME or custom
- ✓ Replies from our sales team, usually within one business day
- ✓ Samples on request, courier freight paid by the buyer