Related Specifications
Surface Treatments
Certifications
- ISO 9001 - 2015 Certified
- PED 2014/68/EC
- NACE MR0175/ISO 15156-2
- NORSOK M-650
- DFAR
- MERKBLATT AD 2000 W2/W7/W10
F436 vs SAE Washer — What is the Difference?
ASTM F436 is a hardened-washer material specification; SAE J78 and J104 are dimensional standards for plain washers. The two cover the same general components (flat washers under bolt heads and nuts) but address completely different requirements: F436 sets metallurgy, hardness and tolerance for structural-bolting service; SAE standards set physical dimensions (outside diameter, inside diameter, thickness) for general-purpose washers without prescribing hardness or grade.
F436 vs SAE Washer Comparison
| Attribute | ASTM F436 / F436M | SAE J78 / J104 (Plain Washers) |
|---|---|---|
| Standard type | Material + dimensional + hardness | Dimensional only |
| Hardness | HRC 38–45 through-hardened (HRC 26–45 hot-dip galv) | None specified |
| Material | Type 1 (carbon) or Type 3 (weathering) | Plain carbon steel |
| Intended use | High-strength structural bolting (A325, A490, F3125) | General-purpose load spreading |
| Bevel/clipped/extra-thick forms | Yes, all four forms standardised | Plain only (some SAE narrow-pattern variants) |
| Issuing body | ASTM International | SAE International |
| Equivalent system | ISO 7415 (high-strength) | ISO 7089, ISO 7090 (regular) |
When SAE Washers Are Acceptable
SAE-pattern plain washers are appropriate for mechanical assemblies where joint preload is not engineered — for example mounting brackets, panel fixings, sheet-metal joints, and machine-element fastening. SAE washers paired with SAE J429 grade 2 or grade 5 bolts work where the bolt is not preloaded near yield. They are not suitable wherever an SAE J429 grade 8 bolt is used at high preload, or wherever A325 / A490 / F3125 high-strength structural bolts are specified.
When F436 Is Required
RCSC (Research Council on Structural Connections) Specification requires F436 hardened washers wherever a high-strength bolt is tensioned per the snug-tightened, turn-of-nut, calibrated-wrench, or tension-control-bolt method. F436 is required (a) under the rotated element — nut or bolt head — on slip-critical and pretensioned joints, (b) under both bolt head and nut on oversized or short-slotted holes (use extra-thick F436), and (c) for any joint using ASTM F3125 grade A325, A490, A325M, or A490M assemblies. SAE plain washers do not meet RCSC.
See Also
Detail F436 reference: F436 specifications, F436 dimensions. Related comparisons: F436 vs F844 (plain unhardened), F436 vs Grade 8 (a common confusion).
Satisfaction Survey
