Classification and application of bucket in rotary drilling

As our previous article wrote, the drilling bucket generally involves its use as a cutting tool to excavate soil or other materials during drilling operations in construction, foundation work, and deep excavation projects. Then do you know how many kinds of drilling bucket in the market and how to select them for your projects? Let see it in this article.

Firstly, let’s see the structure of a bucket. The bucket consists of 10 parts:
1)kelly box
2)Unlocking mechanism
3)Roof
4)Wear block
5)Bucket body
6)Upper bottom plate
7)Lower floor
8)Lower mandrel
9)Accurate
10)Hinge

For now, we have 4 kinds of buckets, including drilling bucket, centrifugal bucket, belling bucket and cleaning bucket.

1.Drilling bucket

The drilling bucket is used for drilling and carry the crushed rock cuttings out of the hole through the drill bucket, and the unloading mechanism will discharge the cuttings. Generally the drill teeth are installed at the bottom to crush rock. The drill teeth are also selected according to the strata. For more details please check the article: How many kinds of drilling bit for choose?

As our previous article wrote, drilling buckets include Soil layer double bottom double opening drill bucket, Soil layer single bottom double opening drill bucket, Rock double bottom double opening drill bucket and Rock double bottom single opening drill bucket. Different drilling buckets are used in difference strata. For more details, please check the article: More details about rotary drilling tools

2.Centrifugal bucket

In drilling operations, the centrifugal bucket can be adjusted and optimized for different construction conditions and formation conditions. For example, when encountering areas with high soil viscosity, the traditional drill bucket may not be able to completely fall off due to the soil adhering to the inner wall, resulting in reduced drilling efficiency. The centrifugal bucket, through its special design, can make some parts of the drill bucket open during the drilling process, so as to more effectively remove the soil adhering to the inner wall of the drill bucket and improve drilling efficiency.

However, with the use of construction, it is found that the centrifugal bucket has stronger drilling ability than the double-bottom drill bucket. Therefore, the centrifugal bucket is not only used for construction in small-diameter plastic formations, dense gravel and gravel layers, low-strength sedimentary rocks, fully/strongly weathered rock formations, etc. The centrifugal bucket can be used for pile diameters ranging from 0.6m to 1.5m.

3.Belling bucket

The expansion pile can effectively improve the bearing capacity of the pile foundation, so the belling bucket came into being. The mechanical belling bucket is a common type of belling bucket. The axial pressure is applied downward by the kelly bar to expand the expansion wing, and the torque is used to rotate the expansion hole wall to meet the expansion design requirements.

4.Cleaning bucket

The structure of the cleaning bucket is basically the same as that of the drilling bucket, except that there are no teeth on the bottom plate, but a scraper is used instead.

The cleaning bucket has the following functions:

Clearing the accumulated soil: The cleaning bucket operates at the bottom of the pile hole, effectively clearing the accumulated soil, reducing the resistance between the pile hole and the soil, thereby improving the bearing capacity of the pile.

Ensuring the depth: By digging out the bottom soil layer, the cleaning bucket can ensure that the depth of the pile hole meets the design requirements, further ensuring the quality and safety of the construction.

Improving the quality of pile formation: In the construction of bored piles, hole cleaning is an important part of ensuring the quality of pile formation. The use of cleaning bucket helps to reduce the thickness of the bottom sedimentation, meet the requirements of the specifications, and thus improve the construction quality of the hole.