Technical Specifications for CONFAST® Concrete Screws
Description:
The CONFAST® brand concrete screw cuts threads in a predrilled hole in concrete, brick or block. The screw has alternating raised and lowered threads with diamond cut notches which provide exceptional holding power and stability. The CONFAST® brand concrete screw is available in either 3/16" or 1/4" diameters with either a flat Phillips #2 or #3 countersunk or a 1/4" or 5/16" hex washer head. All screws are plated which provides extended life and additional lubricity for ease of installation.
Applications:
Light to medium duty in concrete, brick, and block.
Installation:
(1) Drill hole into base material using the drill bit provided with the screws. The depth of the hole must be at least 1/4" deeper than the CONFAST® embedment.
(2) Place object to be fastened over the hole.
(3) Insert point of CONFAST® into the hole and drive screw in using a nut driver or bit tip. Do not over torque the screw.
Screw Length:
The length of the CONFAST® screw to be used is determined by combining the thickness of the material to be attached with the desired depth of embedment in the base material.
Screw Spacing:
As a rule of thumb, the expansion industry has established a minimum standard of ten (10) anchor diameters for spacing between anchors and five (5) anchor diameters from an unsupported edge. Where vibration or sudden impact is part of the load condition anchor spacing should be increased.
Technical Information:
Ultimate Load Values in 2000 PSI Concrete
| Size | Minimum Embedment | Drill Bit | Pull-Out (lbs.) | Shear (lbs.) |
| 3/16" | 1" | 5/32" | 450 | 540 |
| 1/4" | 1" | 3/16" | 562 | 675 |
Ultimate Load Values in Light Weight Block
| Size | Minimum Embedment | Drill Bit | Pull-Out (lbs.) | Shear (lbs.) |
| 3/16" | 1" | 5/32" | 165 | 300 |
| 1/4" | 1" | 3/16" | 187 | 465 |
Ultimate Load Values in Medium Weight Block
| Size | Minimum Embedment | Drill Bit | Pull-Out (lbs.) | Shear (lbs.) |
| 3/16" | 1" | 5/32" | 255 | 547 |
| 1/4" | 1" | 3/16" | 375 | 750 |
Values shown are average ultimate values and are offered only as a guide and are not guaranteed. A safety factor of 4:1 or 25% is generally accepted as a safe working load. Reference should be made to applicable codes for the specific working.