An auger drill is used in the construction and mining industries. It produces a hole through a cutting or gouging motion with the chiseled tip of a drill bit. It is commonly used for environmental and geotechnical sampling.

Contents 1 History 2 Features 2.1 Advantages and Disadvantages 3 How it Works 4 Types 5 Common Manufacturers 6 References

[edit] History

The auger drill can be traced to primitive forms of drilling used in China more than 3,000 years ago. Drills were fashioned out of bamboo and used to bore holes. Before the invention of the internal combustion engine, drilling was carried out by turning rods manually or with the help of animals such as mules.^[1]

Before the oil-drilling boom, brine was a popular material to drill for, and its necessity prompted improvements in these primitive forms of drills. The first modern drills, from the 1900s, were operated mechanically. After World War II, the use of hydraulics and pneumatics was applied to auger drills, making the penetration more accurate and smoother.

[edit] Features

The auger drill comprises a drill rod, which is the shaft that houses the drill bit, or the tip that penetrates the earth’s crust. A series of ropes and cables lowers the rod into the ground so the drill bit can chip away material and produce a hole.

[edit] Advantages and Disadvantages

Auger drilling is considerably less expensive than other types of drilling. It produces a fast rate of penetration if used on suitable formations and is effective for sampling purposes.^[2]

However, the drill becomes less effective and slower if used on harder, consolidated formations.^[3]

Auger drilling is also disadvantageous in comparison to rotary drilling, which doesn’t require the drill to be removed from the hole for the removal of cuttings.

Auger drills can also be dangerous and more hazardous to use than other drill types. The Occupational Health and Safety Administration has imposed training requirements on auger drilling because close contact of fabrics with this drill, in combination with the rotational movement it produces, could cause the clothing to wrap around the drill and cause serious injury to the operator. ^[4]

[edit] How it Works

The auger drill is driven rotationally into the ground and produces a hole with a helical screw-shaped drill bit. Although it is similar to the rotary drill in its rotational drive, it differs in that the drill bit is designed for softer formations.

The auger, which can weigh 110 pounds (50 kg) or more, is lowered into the hole and the drill bit proceeds to chip away cuttings. When enough cuttings are produced, the auger drill is pulled out of the hole and the cuttings and debris are removed. The process is then repeated until the desired depth has been achieved.^[5]

[edit] Types

The most common type of auger is the continuous flight auger. This machine uses a rotational head, which chips away rock, while at the same time pushing the cuttings to the top of the hole with the helical edges found on the drill bit.

Another type is the bucket auger. The bucket auger collects the cuttings in a bucket and brings them to the surface. The bucket auger also comes in handy when the borehole gets deeper, as extensions can be added for easier collection of cuttings.

Augers are available in a variety of sizes, depending on the application. Smaller ones are able to be mounted on trucks, while larger augers, used for sinking piles in bridge construction, are independent. ^[6]

[edit] Common Manufacturers

• Atlas Copco
• Creighton Rock Drill
• Eimco Elecon India
  
• Furkura Rock Drill
• Gardner-Denver
• Herrenknecht AG
  
• Lunzen
• Sandvik
• Terex

[edit] References

1. ↑ Simple Drilling Methods. LBORO. 2008-10-23.
2. ↑ Drilling Methods. Well Drilling School. 2008-10-12.
3. ↑ Simple Drilling Methods. LBORO. 2008-10-23.
4. ↑ Auger Drill Safety. OSHA. 2008-10-12.
5. ↑ Simple Drilling Methods. LBORO. 2008-10-23.
6. ↑ Drilling Methods. Well Drilling School. 2008-10-12.