Dimensional data for M45 Hex Nuts to ISO 4032 / ISO 4033, 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.
M45 Dimensional Row (ISO 4032 / ISO 4033)
| Size | Pitch (mm) | Width across flats s (mm) | Width across corners e min (mm) | Nut height m style 1 (mm) | Nut height m style 2 (mm) | Reference standard |
|---|---|---|---|---|---|---|
| M45 | 4.5 | 70.0 | 76.95 | 36.0 | - | ISO 4032 (Style1) / ISO 4033 (Style2, M5-M36 preferred sizes) |
Spanner & Drive for M45 Hex Nuts
M45 Hex Nuts have a width across flats of 70.0 mm — fit a 70.0 mm open-ended spanner or socket. A 6-point socket grips all six flats of the 70.0 mm hex and is what to reach for once a fastener has been on and off a few times; a 12-point ring spanner starts rounding a worn head. For repeatable preload, torque rather than feel.
Tightening Torque for M45
| Class 8.8 (dry, ~µ 0.125) | ≈ Nm |
|---|---|
| Class 10.9 (dry, ~µ 0.125) | ≈ Nm |
| Class 12.9 (dry, ~µ 0.125) | ≈ 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 M45
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 M45 Hex Nuts
- Use a 6-point socket where access allows — 12-point sockets are more prone to rounding the corners on smaller sizes.
- On flanged or serrated variants, do NOT add a separate flat washer — the flange already spreads the load and the washer can defeat the locking serrations.
- At M45 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 M45
Pair M45 with the matching M45 bolt or screw, plus a M45 flat washer where required to distribute load on softer materials.
Custom manufacturing · Made to drawing
Need hex nuts in a size this table does not list?
This page covers M45 hex nuts. Thread size is the obvious variable and rarely the interesting one — height for clearance, across-flats for the tool already in the cell, and the locking feature for the vibration actually present. Made by cold heading or tapping.
Minimum order from 2,000 pieces; samples within 7 days of drawing approval.
