430 Flat washers
ISO 7089 / ISO 7090
For 430 washers, ferritic stainless performance for mild industrial exposure is only useful with a bearing section that stays flat under load. Bore, outside diameter and thickness match the head or nut to the supported member.
- MOQ
- 100PCS
- Samples · typical
- ~20 days
- Production · typical
- 25–35 days
- Heat treatment
- Annealed
EN 10204 3.1 MTC + heat-number traceability
Which standard is on your order?
Raw Material Specifications
Dimension Reference
Heat Treatment
AnnealedAnnealing reduces work hardening and restores ductility for the specified supplied condition.
What we can make in 430
Normal series
Use under bolt heads and nuts on machined equipment faces with adequate surrounding seat area. The bore must clear the bolt shank and under-head radius so the washer lies flat.
Larger outside diameter
Use over slots, oversized holes and softer mounting surfaces to spread the bearing load. Washer thickness matters as well as diameter: a thin wide washer can dish over an unsupported opening.
Square & special profiles
Use on channel supports, slotted bases and special mounting pads where a round washer leaves insufficient support. Profile and hole position keep the bearing plate seated across the actual opening.
- Geometry
- Bore × outside diameter × thickness
- Forms
- Round · Square · Drawing profiles
- Function
- Bearing surface · Spacing
- Sizing
- Metric · Inch
- Final condition
- Annealed
- Inspection
- Bore · Outside diameter · Thickness · Burrs
Manufacturing route
Small lots can be machined from suitable stock; repeat production uses cut or punched blanks with bore and outer edge finishing.
Heat treatment & final condition
The final annealed or specified strengthened condition is linked to the lot; an aging treatment is not assumed for a solid-solution alloy.
Finished geometry
Thickness, flatness and edge finish establish the bearing geometry; the washer is not labelled hardened solely because the alloy is corrosion resistant.
Where 430 fits — and what matters
Industrial Machinery & Automation
Machine frames and positioning fixtures430 flat washers spread bolt or nut bearing load across machine frames and positioning fixtures, protecting the seating surface and bridging the specified hole clearance. Alignment, operating cycles and replacement access define the working interface.
Automotive & EV Manufacturing Equipment
Assembly fixtures and test-rig frames430 flat washers spread bolt or nut bearing load across assembly fixtures and test-rig frames, protecting the seating surface and bridging the specified hole clearance. Repeated tooling changes require consistent seating and repeatable assembly dimensions.
Pumps, Valves & OEM
Actuator mounts and pump baseplates430 flat washers spread bolt or nut bearing load across actuator mounts and pump baseplates, protecting the seating surface and bridging the specified hole clearance. Repeated maintenance makes fit, engagement and access part of the component specification.
Same washer. Different material priorities.
430 material data316L
Molybdenum-bearing stainless performance in wet equipment.
- Connection priority
- Bearing pressure and resistance to dishing
- Washdown and retained cleaner
- Cleaner concentration, rinse quality and deposits determine the exposure in covered joints. The low-carbon designation does not independently establish a fastener strength class. Include liquid retained at the two bearing faces and the bore around the shank in the exposure description.
17-4 PH
Aging-controlled strength and hardness.
- Connection priority
- Bearing pressure and resistance to dishing
- H900 versus H1150
- The aging condition changes the balance of strength, hardness and toughness. A replacement part needs the specified H condition, especially where contact wear and shock load occur together.
Inconel 625
Solid-solution strength and resistance to aggressive process liquids.
- Connection priority
- Bearing pressure and resistance to dishing
- Annealed or solution-annealed 625
- The delivery condition affects strength and high-temperature response. Keep the specified condition with the component’s mechanical acceptance; 718-style aging is not the strengthening route for 625. Include liquid retained at the two bearing faces and the bore around the shank in the exposure description.
From drawing to documented delivery
- 01Drawing & BOMForm, dimensions and quantity
- 02Material & formingGrade, heat and manufacturing route
- 03Final inspectionGeometry, threads and ordered tests
- 04Documents & dispatchLot records and identified packing
Order documents
- Material identity
- UNS S43000 · heat number · ordered condition
- Final-part acceptance
- Grade chemistry, supplied condition and ordered mechanical requirements.
- Dimensional record
- Bore · Outside diameter · Thickness · Burrs
- Traceability
- EN 10204 3.1 material certificate · production lot · identified packing
Build your 430 washer enquiry
Questions about 430 flat washers
Should the washer use the same alloy as the bolt?
The wetted assembly may need matching corrosion resistance, but the washer also needs sufficient bearing strength and thickness. The bolt grade does not by itself specify a hardened or load-rated washer.