English
Drill pipe is a critical component in the drilling process used primarily in the oil and gas industry. It is a thick-walled, hollow steel pipe that facilitates the drilling of a wellbore. The drill pipe is a part of the drill string, which includes other components like the drill bit, drill collars, and various tools.
Drill pipes have two main functions: they transmit rotational power from the drilling rig to the drill bit, enabling it to cut through geological formations, and they allow drilling fluid to flow down to the bit and back up the wellbore, cooling the bit and removing cuttings.
Drill pipes come in various sizes, strengths, and wall thicknesses, typically ranging from 27 to 45 feet in length. They are made from high-strength steel or aluminum alloys, with special threaded couplings called tool joints for connecting multiple sections.
| Types of Drill Pipe | Drill pipe, Heavy weight drill pipe, API 5DP Drill pipe, Down Hole Drill Rod |
| Standard | API 5D drill pipe |
| Grade | E75, G105, S135, SS-105, X95, X57, X75, X39 |
| Application | For well drilling |
| Out Diameter of Drill Pipe | From 2 3/8" to 6 5/8 |
| Length ranges of Drill Pipe | Range 1: 18 ft. to 22 ft. Range 2: 27 ft. to 30 ft. Range 3: 38 ft. to 45 ft. |
| Drill pipe diameter | Drill pipe ID | Drill pipe weight |
| 2-3/8 inch | 1.815 inch | 6.65 lb/ft |
| 2-7/8 inch | 2.151 inch | 10.40 lb/ft |
| 3-1/2 inch | 2.764 inch, 2.602 inch | 13.30 lb/ft, 15.50 lb/ft |
| 4 inch | 3.340 inch, 3.240 inch | 14.00 lb/ft, 15.70 lb/ft |
| 4-1/2 inch | 3.826 inch, 3.640 inch | 16.60 lb/ft, 20 lb/ft |
| 5 inch | 4.726 inch, 4.000 inch | 19.50 lb/ft, 25.60 lb/ft |
| 5-1/2 inch | 4.778 inch, 4.670 inch | 21.90 lb/ft, 24.70 lb/ft |
| 6-5/8 inch | 5.965 inch, 5.901 inch | 25.20 lb/ft, 27.70 lb/ft |
| Mechanical properties of API drill pipe grades | ||||
| Grade | Yield strength | Tensile strength | API | |
| psi | psi | psi | ||
| N/mm2 | N/mm2 | N/mm2 | ||
| min. | max. | min. | ||
| E-75 | 75,000 | 105,000 | 100,000 | Spec. 5 DP |
| 515 | 725 | 690 | ||
| X-95 | 95,000 | 125,000 | 105,000 | Spec. 5 DP |
| 655 | 860 | 725 | ||
| G-105 | 105,000 | 135,000 | 115,000 | Spec. 5 DP |
| 725 | 930 | 795 | ||
| S-135 | 135,000 | 165,000 | 145,000 | Spec. 5 DP |
| 930 | 1 140 | 1,000 | ||
| Chemical composition requirements | ||||
| Pipe body | Phosphorus | Sulfur | ||
| max. % | max. % | |||
| Pipe body grade E | 0.03 | 0.02 | ||
| Pipe body grades X, G and S | 0.02 | 0.015 | ||
| Tool joint | 0.02 | 0.015 | ||
1. Material Selection: High-strength steel is chosen for its durability and ability to withstand harsh drilling conditions.
2. Pipe Formation: Steel billets are heated and extruded into hollow tubes through a piercing and rolling process.
3. Heat Treatment: The tubes undergo quenching and tempering to enhance strength, toughness, and resistance to wear and fatigue.
4. Machining: Ends are threaded to allow secure connections with other drill string components.
5. Inspection and Testing: Non-destructive testing (e.g., ultrasonic, magnetic particle) ensures quality and detects defects.
6. Coating and Finishing: Anti-corrosion coatings are applied, and the pipe is painted for identification and protection.
7. Final Assembly: Thread protectors are added, and the pipe is prepared for shipment.
Drill pipes are essential in drilling oil and gas wells. They connect the drill bit to the surface equipment, transmitting rotational power and allowing drilling fluid to circulate.
Used to drill deep wells for geothermal energy extraction. They help in reaching high-temperature reservoirs to harness geothermal power.
Drill pipes are used to drill water wells, reaching underground aquifers and enabling water extraction for domestic or industrial use.
In construction, drill pipes are used for geotechnical investigations, drilling boreholes to assess soil and rock conditions.
Drill pipes are used to collect soil and water samples for environmental studies and contamination assessments.
In scientific research, drill pipes help in drilling ice cores, sediment cores, and rock cores to study climate change and geological history.
