Payment & Shipping Terms:
|Type:||Drill Bit||Machine Type:||Drilling Tool|
Concentric overburden drilling system O.D.273mm;guide device;slide block;assembly
Symmetric/Centrex/Symmitrix Drilling System
Symmetric is a concentric drilling system with retrievable pilot bits.
The ring bit will be left in the hole after drilling finished.
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 markettoday.
The Symmetric components are made up of:
---A pilot bits with large internal flushing holes and external flushinggrooves
---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.
There are casing drilling applications where the passage through the ring bit is essential. Such requirement is typical in both piling as well as in well drilling. Symmetrix product range includes models taking this requirement into consideration.
In piling a large pass through ring bit inner diameter is normally required to drill a hole for a rock socket without the casing with a DTH bit. On the other hand the structure of pile reinforcement placed into the casing requires a certain space and when casings are retrieved ring bit inner diameter needs to be large enough.
In well drilling the casing is drilled through overburden into the bedrock and then the drilling of rock well is continued with a DTH bit. For that reason the ring bit inner diameter needs to be large enough.
Sometimes it is economically reasonable to drill the hole for the rock socket with the actual Symmetrix pilot bit. This applies to all cases where the rock socket length is short compared to the casing length. By utilizing the Symmetrix pilot bit for drilling the rock socket, time is saved, since there is no need to replace the Symmetrix pilot bit with a DTH bit between work phases. Symmetrix product family has such drill through systems for both permanent and retrievable casings.
Drill through systems are available for most casing sizes. In the product designation code, not only the ring bit inner diameter, but also the outer diameter of the pilot bit is given since the pilot bit makes a larger hole than the ring bit's inner diameter.
Full face head desigh for faster penetration and straighter hole
Less torque is required
Can drilll in vertical, horizotal or any direction
Minimize disruption to the drilled hole
|Casing Tube||Reamed Hole Dia
|Casing Shoe Inner Dia
|DTH Hammer Type(E)||Drill Pipe
|Outer Dia(mm)||Inner Dia(mm)|