Our specialities


Rock support – combination bolts with long service life


We produce and offer to the market rock anchor bolts with particularly long service life using PC-CoatTM corrosion protection (hot dip galvanizing, zinc manganese phosphating and epoxy powder coating). In order to fully control product quality to very high standards, manufacturing is completely done in our own premises, both mechanical production as well as all steps of corrosion protection.

We are producing two types of combination bolts, NC-Bolt and PC-BoltTM. Combination bolts are effective for immediate work protection at the face after torque tensioning, and when later fully grouted, can be classified as permanent support. Workers are installing rock bolts in the face area while grouting of the bolts takes place at a convenient time and distance behind the face (typically about 50m). Combination bolts contribute to efficient tunnel advance and when needed, we also offer self drilling anchors (SDA), either HDG- or PC-CoatTM protected.

Presentation of combination bolts for download: PowerPoint or PDF.
Installation video of PC-BoltTM and NC-Bolt.

For further information, please contact our sales team:
Erik A. Karlsen, erik@pretec.no, +47 977 13 810 (UTC +1)
Even A. Karlsen, even@pretec.no, +47 908 45 246 (UTC +1)
Tony Tang, tony@chinapretec.com, +86 139 6735 8765 (UTC +8)

Learn more


Learn more about Norwegian Tunneling
See under “Elements of Norwegian Tunneling”:
Temporary and permanent rock bolts in Norway

Other areas


Video introduction to Pretec China – top modern facilities for production of rock support bolts and accessories with long service life. The company is 100% owned by Pretec Group AS.

About Pretec Group

The group companies are manufacturing and supplying products for rock support and water & frost proofing of tunnels, slope stabilization, products for the precast industry, like cast in sleeves, lifting systems, sandwich/connections, welding plates, anchor channels, release agents etc. We also have a program for steel builders and mechanical workshops including tie rods, tension rods, foundation bolts, structural bolts, expansion bolts, hollow bolts, dowels, etc. Our network of dealers offers full on-site service to the general building industry.

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