Symmetric drilling system 

Retrievable symmetric drilling system by DTH hammer is designed to drill and case a hole simultaneously through unstable ground conditions. The driver rock drill bits incorporated with a satisfactory ring or reusable ring makes a full face head design which significantly improves the penetration rate and hole straightness of drilling. The internal flushing grooves together with the built-in casing shoes gives a good seal to the button of the drilling hole, minimizing the disruption of the drill hole's surrounding.

Symmetric Casing Drilling System Features and Advantages:

1. 1)      Stable and reliable working performance

2. 2)      Full face head design for faster penetration and straighter hole

3. 3)      Less torque is required than eccentric drilling

4. 4)      Can drill in vertical, horizontal or any direction

5. 5)      Minimize disruption to the drilled hole

6. 6)      Effective cuttings removal

7. 7)      Unlocking-relocking easily

8. 8)      Easy to operate and system security

9. 9)      Varied ring bit diameters to suit different casing requirement

10. 10)   The less vibration of drill rig

Symmetric Casing Drilling System is designed to drill holes of many sizes, ranging from 108 to 863mm (4 1/4 to 34 in), at any angle (including horizontal), to any depth (beyond 100 meters) through unconsolidated formations simultaneously with casing. The internal flushing grooves together with the built-in casing shoes gives a good seal to the button of the drilling hole, and thus minimizing the disruption of the surrounding of the drill hole. It makes the casing follow easy and the equipment and operation simple, and is recommended to a multitude of applications, such as micro-piling, underpinning, anchoring, marine work and horizontal drilling etc..