B-31 Rock Anchor

B-31 Rock Anchor

rock anchor photo


b 31 rock anchor drawing

The rock anchor is threaded onto the coil rod until the rod hits the backstop of the anchor. The plastic retaining sleeve is removed and the rock anchor/coil rod assembly is placed into the bore hole. The assembly is installed so that the anchor backstop “bottoms” in the bore hole. Tightening the coil rod will draw the anchor wedges forward to expand the anchor’s shell. Care should be taken to not overtighten the anchor.


B-31 Rock Anchor Selection Chart

Coil Rod Diameter Min. Hole Depth “L” Required Hole Diameter “D” Safe Working Load Tension (lbs)
1/2″ 6″ 1-3/8″ 4,500
3/4″ 8″ 1-5/8″ 9,000
1″ 10″ 1-3/4″ 18,000

*SWL provides a factor of safety of approximately 2 to 1.