Symmetric Drilling Tools with Casing Tube

Retrievable Symmetric Drilling tools with csing tube step-by-step:
1. When the drilling starts, the central bit drive the ring bit down the hole, meanwhile the casing shoe and casing tube follow down together.
2.When arriving the bedrock, reversly rotate the tools and the central bit is pulled out from the hole.
3. During pouring the concretes through the casing tube, pull out the casing tube with the ring bit synchroly.

Permanent Symmetric Drilling Tools with csing tube step-by-step:
1. When the drilling starts, the central bit drive the ring bit down the hole, meanwhile the casing shoe and casing tube follow down together.
2. When arriving the bedrock, reversly rotate the tools and the central bit is pulled out while leaving ring bit in the hole bottom.
3. Pouring the concretes into the casing tube or move to next field work process.

Symmetric Drilling Tools with casing tube:
Assembly Code Hammer Drill pipe dia.(mm)
TGZ75-3.5-108/7.5 DHD3.5 76
TGZ80-3.5-114/6 DHD3.5 76
TGZ90-3.5-127/6.5 DHD3.5 76
TGZ103-340-140/6 DHD340A 76
TGZ106-340-146/7.5 DHD340A 76
TGZ121-350-168/10.5 DHD340R 76 / 89
TGZ130-350-168/8 DHD340R 76 / 89
TGZ136-350-178/9 DHD340R 76 / 89
TGZ139-350-183/10 DHD340R 76 / 89
TGZ148-360-194/6.5 DHD360 114
TGZ163-360-219/7 DHD360 114
TGZ163-360-219/12.5 DHD360 114
TGZ218-380-273/11.5 DHD380 114 / 140
TGZ218-380-273/6.5 DHD380 114 / 140
TGZ253-110-324/9.5 DHD110 140 / 194
TGZ338-112-406/9.5 DHD112 194 / 273

Symmetric/Centrex/Symmitrix Drilling System
Symmetric is a concentric drilling system with retrievable pilot bits.
This system drills in any direction and in any type of ground condition.
It is, in fact, the most flexible and efficient overburden system on the market today.
The Symmetric components are made up of:
---A pilot bits with large internal flushing holes and external flushing grooves
---Symmetrical ring bit (reamer) with internal bayonet coupling
---Casing shoe for driving of casing.
The Pilot bits is attached to any common DTH hammer shank.