Material specification page for trapezoidal (metric acme-type) threaded rod in Property Class 12.9 Steel. Covers the grade designation (ISO 898-1 property class 12.9), corrosion and magnetic behavior, comparable grades and their trade-offs, and the sizes available to DIN 103.
Why Choose Property Class 12.9 Steel for Trapezoidal (Metric ACME-Type) Threaded Rod
The highest common strength class, for high-load machine assembly. For trapezoidal (metric acme-type) threaded rod, this matters when requires plating or black-oxide protection is the primary requirement.
Mechanical & Physical Properties
| Grade designation | ISO 898-1 property class 12.9 |
|---|---|
| Magnetic response | Magnetic |
| Service temperature | commonly limited to approx. +300 °C; confirm against the coating and the load |
| Corrosion characteristic | Requires plating or black-oxide protection |
Corrosion Behavior in Service
Carbon and alloy steel trapezoidal (metric acme-type) threaded rod require a coating for corrosion protection. Zinc plating (with or without passivation) is the most common; hot-dip galvanizing is used for outdoor structural service; black-oxide is mainly a tarnish-prevention finish for tool-room use.
Comparable Grades
For Trapezoidal (Metric ACME-Type) Threaded Rod, class 8.8 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 Trapezoidal (Metric ACME-Type) Threaded Rod Available in Property Class 12.9 Steel
| Size | Pitch P (mm) | Clearance ac (mm) | Reference standard |
|---|---|---|---|
| Tr8 | 1.5 | 0.15 | DIN 103 |
| Tr9 | 2 / 1.5 | DIN 103 | |
| Tr10 | 2 / 1.5 | DIN 103 | |
| Tr11 | 2 / 3 | DIN 103 | |
| Tr12 | 3 / 2 | DIN 103 | |
| Tr14 | 3 / 2 | DIN 103 | |
| Tr16 | 4 / 2 | DIN 103 | |
| Tr18 | 4 / 2 | DIN 103 | |
| Tr20 | 4 / 2 | DIN 103 | |
| Tr22 | 5 / 3 / 8 | DIN 103 | |
| Tr24 | 5 / 3 / 8 | DIN 103 | |
| Tr26 | 5 / 3 / 8 | DIN 103 | |
| Tr28 | 5 / 3 / 8 | DIN 103 | |
| Tr30 | 6 / 3 / 10 | DIN 103 | |
| Tr32 | 6 / 3 / 10 | DIN 103 | |
| Tr34 | 6 / 3 / 10 | DIN 103 | |
| Tr36 | 6 / 3 / 10 | DIN 103 | |
| Tr38 | 7 / 3 / 10 | DIN 103 | |
| Tr40 | 7 / 3 / 10 | DIN 103 | |
| Tr42 | 7 / 3 / 10 | DIN 103 | |
| Tr44 | 7 / 3 / 12 | DIN 103 | |
| Tr46 | 8 / 3 / 12 | DIN 103 | |
| Tr48 | 8 / 3 / 12 | DIN 103 | |
| Tr50 | 8 / 3 / 12 | DIN 103 | |
| Tr52 | 8 / 3 / 12 | DIN 103 | |
| Tr55 | 9 / 3 / 14 | DIN 103 | |
| Tr60 | 9 / 3 / 14 | DIN 103 | |
| Tr65 | 10 / 4 / 16 | DIN 103 | |
| Tr70 | 10 / 4 / 16 | DIN 103 | |
| Tr75 | 10 / 4 / 16 | DIN 103 |
Dimensions are independent of the material: every size above is available in Property Class 12.9 Steel.
Custom manufacturing · Made to drawing
Need this bolt in a grade that is not listed?
Grade 12 9 Steel is one of the grades the catalog describes. A non-standard bolt is quoted from the drawing; where one already exists in the catalog, the special is usually a variation on its tooling. Made by cold heading or hot forging.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
