Milsons Purlin Bolts comprise of a property 8.8 flange bolt and a class 8 flange nut, and are available in either a zinc plated or hot dip galvanised finish. Refer to the table below for indicative tightening torque.
| Part No. | Finish | Thread Size (D) | Bolt, mm | Nut, mm | Indicative Tightening Torque (N-m) (T) | Resulting Bolt Tension (P) | |||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Across Flats (AFb) | Head Height (m) | Flange Diameter (øB) | Bolt Length (L) | Across Flats on Nut(AFn) | Nut Flange Diameter (øu) | Nut Height (n) | |||||
| PBN8812X30G | Galv | M12 | 18 | 10.5 | 27.5 | 30 | 18 | 28 | 12.5 | 73.35 | 24,450 |
| PBN8812X30Z | Zinc | M12 | 18 | 9 | 27.5 | 30 | 18 | 28 | 12.5 | 64.55 | 24,450 |
| PBN8816X35G | Galv | M16 | 24 | 13.5 | 32 | 35 | 24 | 32 | 17.5 | 182.0 | 45,500 |
Indicative tightening torque (T) is calculated using the basic formula
T = P x k x D
Where:
P: Intended Bolt tension (Assumed to be 50% of the bolt’s proof load)
k: Is the torque-friction factor (Zinc plated assemblies: 0.22, Galvanised assemblies: 0.25)
D: Is the thread diameter
Note that the k value can vary depending on thread conditions, thread/bearing lubrication, and site conditions. All bearing surfaces are assumed to be in full contact as shown in fig 1.
Installation Instructions
As shown in figure 1. The base of the head as well as the base of the nut should be in full contact with the fastened component(s).
The data provided in this document is for general guidance only and should not be solely relied upon when working to stringent specifications. We recommend consulting with qualified experts regarding any technical queries. This may change without written notice
Version No: 231108
