how does wedge anchor work

A wedge anchor is a mechanical type expansion anchor that consists of four parts: the threaded anchor body, the expansion clip, a nut, and a washer. These anchors provide the highest and most consistent holding values of any mechanical type expansion anchor.

Secondly, how deep do wedge anchors need to be? The hole needs to be drilled a minimum of 1/2” deeper than the anchor will penetrate the concrete. Each diameter anchor has a minimum embedment for installation to allow the anchor to achieve its minimum holding values.

Beside above, how does an anchor bolt work?

Anchor bolts are used to connect structural and non-structural elements to the concrete. The connection is made by an assembling of different components such as: anchor bolts (also named fasteners), steel plates, stiffeners. Anchor bolts transfer different types of load: tension forces and shear forces.

Drilling the Hole:
To install a wedge anchor in concrete, a hole must be drilled into the concrete.  The hole must be drilled using a carbide bit in a hammer drill in the hammer and rotation mode to ensure proper hole size and consistency.  Drilling a hole in concrete with a standard rotation drill may create a hole that is not suitable and may not meet the tolerance requirements of the wedge anchor.  The tolerance between the hole size and wedge anchor size is critical for the wedge anchor to achieve its holding values.

• Hole diameter for wedge anchors equals the wedge anchor diameter being installed; a 3/4” wedge anchor requires a 3/4” hole.
• Carbide tipped bit must meet ANSI standard to ensure proper tolerance between the hole diameter and wedge anchor.
• The hole must be cleaned out to ensure that the wedge anchor will be properly installed.
• Make sure that the hole is a minimum of 1/2” deeper than the wedge anchor will penetrate the concrete.  This extra space will ensure that the wedge anchor does not bottom out in the hole and allows space for any dust to fall into that is created during the installation of the wedge anchor.

Inserting Wedge Anchor:

• Directly into Concrete - Once the hole in the concrete has been drilled then the wedge anchor can be inserted into the hole.
  • Thread a nut onto the threaded end of the wedge anchor to protect the threads when struck by the hammer. 
  • Insert the wedge anchor, expansion clip first, into the hole. 
  • Strike the nutted end of the wedge anchor with a hammer until a minimum of 5 to 6 threads are below the surface of the concrete. 
  • Using your fingers, tighten the nut snugly.
  • Then, using a wrench, turn the nut clockwise 3 to 4 turns or until the proper torque values for the diameter of wedge anchor being used are reached.

• Through a Fixture Hole - Once the hole in the concrete has been drilled, the wedge anchor can be inserted through the fixture hole and into the hole in the concrete.  The hole in the fixture must be slightly larger than the nominal diameter of the wedge anchor being installed. For example, a 3/8” diameter wedge anchor requires a hole in the fixture to be a minimum of 7/16” diameter

• Once the fixture hole size has been determined to be large enough to accept the diameter of wedge anchor to be installed, thread a nut onto the threaded end of the wedge anchor. This will protect the threads when stuck by the hammer. 

• Insert the wedge anchor, expansion clip first, into the hole. 

• Strike the nutted end of the wedge anchor until a minimum of 5 to 6 threads are below the surface of the material being fastened. 

• Use your fingers to tighten the nut snugly. Then, with a wrench, turn the nut clockwise 3 to 4 turns or until the proper torque values for the diameter of wedge anchor being used are reached.