Double rotary drilling

Double rotary drilling

Double rotary drilling

Procedure of producing a cast-in-place concrete pile with double rotary drilling:
1. Positioning at the drilling point
2. Auger drilling with simultaneous advance of the casing
3. Extraction of auger and casing while concrete is pumped in through hollow stern
4. Inserting the reinforcement
5. Finished pile

Double rotary drilling combines continuous flight auger drilling with a continuous casing. Casing and auger (inside the casing) are simultaneously installed and extracted. Double rotary drilling is applied for the production of cast-in-place piles and for predrilling.

Examples with double rotary drilling

  • This method combines continuous flight auger drilling with a casing. It is mainly applied for producing cast-in-place piles.

    Combination of continuous flight auger and casing

    This method combines continuous flight auger drilling with a casing. It is mainly applied for producing cast-in-place piles.

  • Two rotary drives are separately mounted on the sledge and independently drive the inner continuous flight auger and the casing.

    Double rotary drilling

    Two rotary drives are separately mounted on the sledge and independently drive the inner continuous flight auger and the casing.

  • During the drilling process the auger flights convey the drill cuttings to the surface inside the casing. Through an opening at the upper end of the auger the drill cuttings are ejected.

    Installing cast-in-place piles

    During the drilling process the auger flights convey the drill cuttings to the surface inside the casing. Through an opening at the upper end of the auger the drill cuttings are ejected.

  • The compact design of the double rotary head allows operation very close to existing building structures, i.e. in front of building walls.

    “Front-of-wall” drilling

    The compact design of the double rotary head allows operation very close to existing building structures, i.e. in front of building walls.

  • A protection cover encloses the casing so creating an annular space inside. Thus, the ejected drill cuttings fall to the ground in a controlled manner.

    Protection cover

    A protection cover encloses the casing so creating an annular space inside. Thus, the ejected drill cuttings fall to the ground in a controlled manner.

  • After their extraction, casing and auger are swung to the side and emptied by rotating the auger in the reverse direction.

    Emptying the auger

    After their extraction, casing and auger are swung to the side and emptied by rotating the auger in the reverse direction.

  • After the final depth has been reached concrete is pumped through the auger’s hollow stem. During the extraction process the concrete exits at the lower end of casing and auger.

    Extracting and concreting

    After the final depth has been reached concrete is pumped through the auger’s hollow stem. During the extraction process the concrete exits at the lower end of casing and auger.

  • After concreting a reinforcement cage can be inserted in the column of fresh concrete. For this purpose the auxiliary winch of the carrier machine is used.

    Reinforcement

    After concreting a reinforcement cage can be inserted in the column of fresh concrete. For this purpose the auxiliary winch of the carrier machine is used.

Video double rotary drilling

Rotary drilling rigs LB 16 and LB 44 in operation with double rotary drilling equipment.

The video shows two jobsites with double rotary drilling for producing cast-in-place piles. Play video

Rotary drilling rigs LB 16 and LB 44 in operation with double rotary drilling equipment.

Find your product

Which product is right for you?
Here is an overview of our machines and equipment.