Dimensional data for M20 Left-Hand Thread Hex Nuts to DIN 934, with the drive and the installation notes for this type.
Values are taken from the governing standard rather than from a general machine-thread table, because this type is not selected on one.
M20 Dimensional Row (DIN 934)
| Thread size | Pitch (mm) | Across flats s (mm) | Across corners e (mm) | Nut height m (mm) | Thread direction | Reference standard |
|---|---|---|---|---|---|---|
| M20 | 2.5 | 30 | 33.53 | 16.0 | Left-hand | DIN 934 LH |
Spanner & Drive for M20 Left-Hand Thread Hex Nuts
Drive geometry for M20 Left-Hand Thread Hex Nuts is given by the row above; match the tool to the listed values.
Tightening Torque for M20
| Class 8.8 (dry, ~µ 0.125) | ≈ 420 Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ 598 Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 700 Nm |
Indicative dry-joint values. Lubrication can lower the required torque by 15–25%. Always confirm against the joint design, especially when going up a strength class.
Proof Load & Strength for M20
Nuts are graded to ISO 898-2 by the proof load the nut itself will hold (classes 04, 05, 5, 6, 8, 10 and 12), not by the 8.8 / 10.9 / 12.9 scale used for bolts. A class-8 nut is the correct mate for a class-8.8 bolt, and the joint is designed on the bolt, so no bolt-tension figure is quoted here.
Installation Tips for M20 Left-Hand Thread Hex Nuts
- At M20 the stretch in the bolt becomes the controlling factor — for critical joints, use angle-controlled or stretch-controlled tightening instead of pure torque.
Mating Parts for M20
Pair M20 with the matching M20 bolt or screw, plus a M20 flat washer where required to distribute load on softer materials.
Custom manufacturing · Made to drawing
Need left-hand thread hex nuts in a size this table does not list?
This page covers M20 left-hand thread hex nuts. Locking method is specifiable independently of the rest: nylon insert, all-metal deformed thread, serrated flange, or none. Made by cold heading or tapping.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
