Wednesday, April 4, 2012

RIG SYSTEM



source : http://static.ddmcdn.com/gif/oil-drilling-derrick.gif

1. The Power System
Generates and distributes the primary power required to operate almost all other component systems and their sub-components in a modern rotary drilling complex.
A drilling rig cannot operate without power. The primary function of the power system is to support all of the other systems by providing a source for the energy required to perform their operations. The most common source of power comes from internal-combustion engines. Theses engines, or prime movers, are normally fuelled by diesel.

2. The Rotating System
Rotates the drilling string and makes the bit drill a subsurface hole, called a “well bore” until it penetrates a potentially productive formation below.
The rotating system is one of the most important components in the rig. Its primary function is to rotates the drilling string and makes the bit drill a subsurface hole.
The rotating system has three major sub-components:
1. The rotary table and / or top drive assembly.
2. The drilling string (drill pipe, heavy weight drill pipe, drill collar, stabilizer, crossover sub, etc.)
3. The bit.

3. The Hoisting System
Supports the rotating system in “drilling the well” by providing the appropriate equipment and working areas needed for lifting, lowering and suspending the tremendous weights required by the rotating system.

4. The Circulating System
Supports the rotating system by proving the equipment, material and working areas to prepare, maintain and revise the drilling fluid (mud).

5. The Blowout Prevention System (BOP)
Helps to control one of the major problems that may be encountered when drilling a well – a “kick” which may develop into a blowout.

Monday, March 26, 2012

Types of Drilling Rigs


A drilling rig is a masive structures housing equipment machine which creates holes in the ground to get something was targeted (water, oil, gas, or oil & gas (both)).  Drilling Rig Can be broadly divided into 6 different types :

Land Rig
Land Rig only drill at onshore, Is moved using heavy transport equipments (HiBed Trailer, LowBed Trailler) and cranes. Land Rig typically come in light, medium or heavy configuration. Small Rig can move with its carrier, also called rig mobile. But, the biggest have very complete configuration. Its need much time to setting up at drilling location. Small rigs may only drill to a few thousand feets. But larger ones are capable of 20000 feets or more.
Submersible Rig / Barge
Tend to drill in fairly shallow water. They flood the legs with water and submerge.Some of the rig is above water, and crews drill from that location. Swamp type, river and inland bay areas are very suitable for some of these rigs. Specially constructed submersibles are also used in extremely cold areas. Typical water depths are 20 feet.
Jack-up Rig
Have lattice legs which can be hoisted and lowered at will. They are hoisted and the rig is either towed or transported by ship. When in location, the legs are lowered to the sea-bed. Jack-up rigs can drill in water depths up to 300feet.
Platform Rig / Tender
Platform Rig are immobile once built. Platform Rig drill several wells from the one location. They can be tender assisted. Three types of Platform are: Steel Jacket, Caisson Type and Concrete Gravity.
Semi-submersible Rig
Has hollow legs and pontoons. Like the submersible, the legs are also flooded. However, anchors and/or Thrusters and Positioners keep the rig in position, When thrusters are used, it is called Dynamic Positioning (computer controlled), This system steadies the rig over the hole. Crews use a Subsea Blowout control preventers.
Drill Ship Rig
Are self propelled, floating offshore drill units, they use a Subsea Blowout control system similar to Semi-submersibles. A template which has holes drilled though it is fitted to the sea bed. This is where the drilling is to take place. The Semi-submersible and Drillships align themselves over these templates. Then they commence drilling.

Typical Land Rig Organization
  1. Rig Superintendent
  2. Toolpusher 
  3.  Driller
  4. Ast. Driller
  5. Derrick Man 
  6.  Floor Man 
  7.  Roustabout 
  8.  Mud Boy 
  9.  Cutting Boy 
  10.  Mechanic Crew 
  11.  Electric Crew 
  12.  Matrial man 
  13. Adm. Rig. 
  14.  H.S.E. Officer