What is Symmetric Casing System
The Symmetric Casing System is suitable for drilling operations such as foundation building, piling construction, drilling for water wells and geothermal energy, tunneling, and horizontal drilling in various types of ground conditions.
Together, the center drill bit and the concentric sleeve outside the center drill bit contact the rock drill hole, and the concentric sleeve's reaming action gently inserts the casing into the hole. The concentric sleeve remains in the hole after the center drill bit is removed once it has reached the bedrock.
Since the Symmetric Casing System uses concentric full-face drilling, the risk of a stuck drilling accident is much lower than it would be with eccentric or pipe drilling. Additionally, the hammer's effective impact frequency is greatly increased, resulting in a smaller borehole diameter and reduced Symmetric Casing System resistance.
Steps for Symmetric Casing System：
1. The integrated shoe and ring bits assembly for the casing are welded to the casing before drilling, and the assembly is then locked into the pilot bits with a hammer to begin drilling.
2. Leave the casing, casing shoe, and ring bits in the hole after installing the casing in the necessary overburden bedrock. Simply unlock the pilot bits with a reverse rotation to remove the drill strings with the pilot bits removed.
3. Either carry on drilling using standard drill strings or remove the casing, casing shoe, and ring bits for further processing.
