9.2: Major Systems on a Drilling Rig | PNG 301 - Dutton Institute

While there are different types of drilling rigs, these rigs obviously share many similarities since the tasks that they perform are identical. In particular, all modern hydrocarbon rotary rigs contain five main systems. These systems are:

For more information, please visit JK Drilling.

• the Power System
• the Hoisting System
• the Rotary System
• the Circulation System
• the Well Control System (Blowout Prevention System)

These systems are shown in Figure 9.01. In addition, Figure 9.02 shows a more detailed schematic diagram of a rotary table, land rig.

Figure 9.01: Major Systems in a Modern Rotary Rig

Source: Serintel: Oil and Gas Portal Drilling Technologies

Figure 9.02: Sub-Systems in a Modern Rotary Rig

1. crown block
2. mast
3. monkey board
4. traveling block
5. hook
6. swivel
7. elevators
8. kelly
9. kelly bushing
10. master bushing
11. mousehole
12. rathole
13. drawworks

14. weight indicator
15. driller's console
16. doghouse
17. rotary hose
18. accumulator unit
19. catwalk
20. pipe ramp
21. pipe rack
22. substructure
23. mud return line
24. shale shaker
25. choke manifold
26. mud gas seperator

27. degasser
28. reserve pit
29. mud pits
30. desander
31. desilter
32. mud pumps
33. mud discharge lines
34. bulk mud components storage
35. mud house
36. water tank
37. fuel storage
38. engines and generators
39. drilling line

Source: Serintel: Oil and Gas Portal - Drilling Technologies

Water Well Drilling Machine

In a broad sense, drilling rigs can be classified as fixed or mobile. These terms describe the ability of a drilling rig to leave the drilling site quickly when necessary. This classification is broad and there is little definition of each rig type.

 

The land and marine classifications provide a more logical grouping of rig types. While there are more types of offshore rigs to choose from, there are more land rigs in use today.

 

Cable tool rigs. Cable tool rigs have played a key role in the history of the drilling industry. Although not in widespread use today, these rigs accounted for about 20% of all wells drilled in the United States in . Many shallow Ohio, West Virginia, and Pennsylvania wells (3,000 feet) are currently drilled by cable tool rigs.

 

Drilling with a cable tool rig is accomplished by lifting a special drill bit and placing it into the formation. The drill column consists of a drill bit, a drill pipe, a shocker, and a rope sleeve for attaching the tool to the drilling tool.

 

Portable (wheel-mounted)

 

Cable tools

Rotary drill rigs

Standard derricks

Conventional

 

Land rigs. The most common land rigs use standard derricks, truck-mounted derricks, or component rigs. The American Petroleum Institute provides various documents related to these rig types, including API Specifications 4E and 8A and Standards 4A and 4D.

Want more information on Crawler Mounted Pneumatic Tophammer Drill Rig? Feel free to contact us.

 

Standard derricks. The oldest rotary rigs in the drilling industry use standard derricks. Derricks are built at the drilling site prior to drilling and are usually removed before being moved to the next location. Many times, the derrick is left above the well after production begins in case it needs to be repaired.

 

Early in its history, the standard derrick was an advancement in cable tool drilling rigs because it could be designed with enough strength and height to run longer casing joints and pull two, three or even four pipe joints. Combination derricks with integral lift rather than integral lift.

 Rock Blasting Drilling Rig

 

Piecemeal construction has replaced standard derricks. Standard derricks take too long to set up and take down. In addition, combination derricks typically have fewer failures than derricks built and disassembled for each well.

 

Portable rigs. Portable rigs are often thought of as truck-mounted units. The truck chassis contains the derrick, winch, and mud pump. A major advantage of portable rigs is the short setup and teardown time and the low truck rental requirements. Portable rigs are often used for workover operations and when drilling to depths of approximately 10,000 feet. These rigs can be used 8, 12, or 24 hours per day.

 

Portable units for drilling are typically limited to light-duty work. Where applicable, the unit is usually the most cost-effective rig.

 

Since most of the world's wells are drilled to depths of less than 8,000-10,000 feet, portable rigs play an important role in drilling operations.

 

Care must be taken when planning wells that are near the upper limit of the portable rig's capacity. For example, if a 3'/z- or 4-in drills a well to 10.000 feet, it will not deform a large portable rig. A drill pipe is used. However, if 23.0 lb/ft of casing must be run to 10,000 ft, then the total casing load (230,000 tb) does not provide an adequate safety factor associated with derrick capacity. While short-term economics may suggest using a portable rig rather than a larger, more expensive conventional rig, a larger rig may be more economical in the long run if drilling problems arise.

 

Conventional rigs. Conventional rigs are often considered component rigs in which key components are so large that they cannot be transported on a single truck chassis. These rigs have depth ratings ranging from 6,000 feet to 35,000 feet. Conventional rigs typically operate 24 hours a day.

 

Marine Rigs. Drilling rigs used offshore are termed marine rigs. A common grouping system for marine rigs is based on the bottom support of the rig on the seafloor. A bottom-supported rig rests on the seafloor or on pads built on the seafloor. 

For more information, please visit DTH drill pipes.