Address:Jennmar Industry Park, Tongji Road, Gaoxin District, Jining, Shandong, China
Tel:0537-2480366, 2480336
Fax:0537-2480338
Contact:Li Li
E-mail:liliyf2@163.com
High strength pre-tension yieldable bolt ⅠR 〔Patent pending〕
Technical Merits：
High pre-tension: Pretension is one of the most important factors to control the surrounding strata effectively. Facilitated with specially made torque-tension nut and “sandwich” harden washer system, this bolt can increase pretention by 30%-50% compared with other similar bolts.
High strength: Using grade 500 rebar, this bolt has higher capacity. Specially treated thread reduces the steel working hardening and the thread part has the same strength as the rebar.
Yieldable: Specially designed yield device characterizes this bolt as yieldable bolt. When the head reaches the yield point of the rebar, the yield device kicks in steadily to prevent the bolt from being broken off.
Distributing load evenly among each bolt: Yield device can distribute the load among the bolts evenly to avoid individual bolt taking extra load and being broken.
Load indicator: A load indicator is designed to monitor the install load, yield load of the bolt. The adequate install load is critical to the effectiveness of bolts. Yield load is an indication of overloaded bolt,
Application：
This bolt has been successfully applied in difficult Mining and geological conditions such deep cover, high stress, large deformation, soft rock, yield pillar and dynamic stress etc.
