Tunnel Bolt

SUYU not only produces rail fastening, but also produces tunnel construction bolts. Our main tunnel bolt products are listed below.

1. Square flange bolts with round thread for tunnel construction
Diameter: 25mm
Length from 400mm to 500mm
Tension strength is more than 700MPA
Surface: Yellow Zinc or according to clients' requirement
Packing: 600pcs in wooden case

2. Curved tunnel bolt

Dimension: 3/4-10 UNC2A

Length ranges 300mm to 500mm

Grade: 4.8

Surface: HDG or according to clients' requirement

Packing: Plastic bags and wooden pallets

3. Spear bolts with plastic socket

Our spear tunnel bolt with plastic socket is manufactured according to customer’s individual requirements. You can specify the length, diameter, steel grade, and choose from a range of surface finishes (e.g. galvanized, bright zinc plating, etc.). They can be supplied in grade 4.6 and 8.8.

Plastic socket sizes are available in:
M20 x 100, M20 x 120, M20 x 130, M20 x 135, M24 x 100, M24 x 110, , M24 x 120, M24 x 135, M24 x 140, M24 x 150, and M24 x 160.

The large thread design on the socket allows the tunnel bolt to be inserted 4 to 5 times faster than traditional metric thread. The design of the threads utilizes the strength of the concrete (as the load is transmitted through the concrete) therefore not relying on the strength of the plastic. This tunnel bolt is available in any length, grade, and finish to suit customer requirements.

Sticking to our quality first policy, SUYU pays great attention to quality control management on tunnel bolt. We have been granted ISO9001-2000 certificates and have received the production license of China’s Railway Ministry on railway products. We have a full set of inspection instruments to ensure all our tunnel bolts are of high quality and up to customers’ requirements.

As a leading manufacturer of rail fastening based in China, SUYU also produces many other railway fasteners, such as track bolt, sleeper screw, track spike, tie plate, rail clip, elastic rail clip, SKL tension clamp, rail shoulder, and so on .