Curve Spear Tunnel Bolt for Concrete Ring

• Customization: Available
• Certification: Crcc
• Product Grade: 4.6, 5.6, 8.8, 10.9
• Model NO.: TB
• Usage: Concrete Ring Connect for Tunnel
• Size: M20, M24 and Other Size Bolt
• Surface Finish: Plain, Black, Phosphate, Zinc, HDG
• Inspection: Internal and 3rd Parties
• Sample Policy: Sample Free, Freight Collect
• Production Update: Weekly Reports Will Be Provided
• Application: Tunnel Building
• Raw Material: Q235, 35#, 45#, 35CrMo, 42CrMo, 40cr
• Inspection Reports: Chemical Composition, Physical Property and Sizes
• Transport Package: Woven Bag and Wood Pallet
• Specification: SGS
• Trademark: ZBRF
• Origin: China
• Production Capacity: 1800000 Tons

Product Description

Zhongbo Railway Fastening Company is a leading Chinese manufacturer of rail fastening and rail joint bar.

Zhongbo, as a specialized rail fastener manufacturer, provides a complete line of products, including rail fastening, anchor, rail joint, rail clip, rail screw, anchor bolt, rail clamp plate, rail fishplate, and fishplate bolt for connecting rail tracks.

We also make rail fastenings for crane rail and elevator guide rail, along with other related products. We manufacture according to GB/TB (Chinese national standards and railway standards), AREA, UIC, BS, DIN, ASTM, and AS standards.




Our products are mainly made through hot forging.

The threads of rail screw spikes are made by hot rolling with special threading machines.

We produce metric threads, BS, BSW, TR thread, or round threads.

Our high strength bolts come in different specifications of Class 4.8, 4.6, 5.6, 5.8, 6.8, 8.8, 10.9, and 12.9. A variety of non-standard fastening is also available. We can customize our products using customer drawings or samples as well.