Eccentric Casing Systems

Eccentric is the most economical solution because its ingenious reaming wing the bit is retrievable can be used at the next hole. 
This is particularly design for shallow holes, as is often the case in water well drilling, geothermal wells, and shallow micro-piling work. 
The component of the Eccentric system consists of Pilot bits / Reamer bits / Guide device / and casing shoe.

Wooke Eccentric Casing Systems




          ► Hardening treatment of the part's surface with longer operation life and excellent anti-wear properties.


         ► Structural Optimisation, improving the structural strength and ease of operation.


         ► Superior Performance, high drilling speed with stable and reliable performance.


Application Range: 


           It is suitable for drilling water wells, geothermal wells, short micropyles, medium mini-type, grouting holes of building & demand harbor projects.

          When drilling, the reamer bit will rotate out to enlarge the hole which is enough for the casing tube to slide down behind the reamer. When reached the required depth, the drill pipe will drill in the reverse direction and the reamer bit will retract, it is allowing the whole drilling system to pass through the casing.

          The below size of Eccentric systems which are the most popular type, and also the special design is upon customer's requirement.

           Eccentric 90 / Eccentric 114 / Eccentric140 / Eccentric 165 / Eccentric 190 / Eccentric 240


Eccentric Drilling tools with casing tube step-by-step:




            ♦ 1. When drilling, the TGZ reamer swings out and drills a hole wide enough for the casing tube to slide down behind the reamer.


          ♦ 2. When the required depth is reached, the drills are reversed, and the reamer swings in, allowing the bit to pass through the casing.




            ♦ 3. The casing tube is pulled out directly or fixed at the bottom of the hole by means of cement grout or other agglutinants.


           ♦ 4. Drilling continues to the desired depth using conventional DTH equipment.


Eccentric Casing Systems Specifications: