Property Class 8.8 Steel (ISO 898-1 property class 8.8) is the workhorse medium-carbon alloy class for structural joints. When custom slotted round nut are specified in this grade, the dimensions remain per GB/T 812; the material determines corrosion behavior (requires plating (zinc) for corrosion protection) and the service temperature range (commonly limited to approx. +300 °C; confirm against the coating and the load). Both are covered below with the size table.
Why Choose Property Class 8.8 Steel for Custom Slotted Round Nut — GB/T 812 (Series 070)
The workhorse medium-carbon alloy class for structural joints. For custom slotted round nut — gb/t 812 (series 070), this matters when requires plating (zinc) for corrosion protection is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 898-1 property class 8.8 |
|---|---|
| Magnetic response | Magnetic |
| Service temperature | commonly limited to approx. +300 °C; confirm against the coating and the load |
| Corrosion characteristic | Requires plating (zinc) for corrosion protection |
Galvanic & Galling Considerations
For custom slotted round nut — gb/t 812 (series 070) in steel, the dominant compatibility issue is hydrogen embrittlement at high property classes (10.9 and above) when electroplated. Plating must be followed by an appropriate baking treatment, or a non-electroplated finish (mechanical zinc, zinc flake) should be substituted.
Comparable Grades
For Custom Slotted Round Nut — GB/T 812 (Series 070), class 10.9 or 12.9 is the comparable strength step. Move up when the joint preload approaches the proof load of the current class; move down when the joint is over-specified. For corrosion-critical service, switch to stainless A2 or A4.
Sizes of Custom Slotted Round Nut — GB/T 812 (Series 070) Available in Property Class 8.8 Steel
| Size | Pitch (mm) | Outer diameter D (mm) | Nut height m (mm) | Slot width (mm) | Slot depth (mm) | Reference standard |
|---|---|---|---|---|---|---|
| M10x1.0 | 1.0 | 18 | 8 | 3 | 2 | GB/T 812 / DIN 1804 |
| M12x1.25 | 1.25 | 22 | 8 | 3 | 2 | GB/T 812 / DIN 1804 |
| M16x1.5 | 1.5 | 28 | 8 | 4 | 2.5 | GB/T 812 / DIN 1804 |
| M20x1.5 | 1.5 | 34 | 10 | 4 | 2.5 | GB/T 812 / DIN 1804 |
| M24x1.5 | 1.5 | 40 | 10 | 5 | 3 | GB/T 812 / DIN 1804 |
| M30x1.5 | 1.5 | 48 | 12 | 5 | 3 | GB/T 812 / DIN 1804 |
| M36x1.5 | 1.5 | 58 | 12 | 6 | 3 | GB/T 812 / DIN 1804 |
| M48x1.5 | 1.5 | 72 | 15 | 6 | 4 | GB/T 812 / DIN 1804 |
| M60x2.0 | 2.0 | 90 | 18 | 7 | 4 | GB/T 812 / DIN 1804 |
| M80x2.0 | 2.0 | 115 | 20 | 8 | 5 | GB/T 812 / DIN 1804 |
| M100x2.0 | 2.0 | 140 | 22 | 10 | 5 | GB/T 812 / DIN 1804 |
Dimensions are independent of the material: every size above is available in Property Class 8.8 Steel.
Custom manufacturing · Made to drawing
Need this nut in a grade that is not listed?
Grade 8 8 Steel is one of the grades the catalog describes. Height and across-flats are the two most often changed — a thinner nut for clearance, a larger hex for a tool that is already on the line. Made by cold heading or tapping.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
