The technology used in underbalanced drilling (UBD) is approximately eleven years, although some variations such as perforation and flow with 30 or more years. The use of a closed loop control in the UBD was designed primarily for the drilling of low pressure in Canada to help eliminate the problems of horizontal drilling. To be effective the UBD is necessary to reduce the hydrostatic pressure of drilling fluid, to avoid damaging the formation during drilling and to eliminate the chances for the submission of a differential sticking and lost circulation. A further advantage of this technology is the increased penetration cup drilling difficult formations.
Conventional mud systems were not able to do this because the slightest presence of sludge could cause serious damage due to fluid invasion. The damage caused during drilling operations, stimulation required to remove the top layer. Many times this process was not successful, resulting in a well that is not profit. The problems of sticking of the drill string and loss of movement were very common in these formations.
The result of applying these techniques were flowing wells during the drilling process. This required the development of a surface control equipment to handle the flow at the time of drilling, it is then that raises the age of underbalanced drilling.
Under Balance Drilling Units
* Fully portable equipment: Part of a trailer that just needs to be moved. In general, the underbalanced drilling equipment is built on platforms.
* Lifting trailer.
* High pressure separators: Most underbalanced separators handle a pressure of 250 psi., While Reform has a separator pressure of 500 psi.
* Multiple entries with covers: Most of the separators has only one entry, which means they have to be inactive when worn.
* Multiple spray system compartments.
* Variable Speed Worm: This removes the solids from the separator and can be adjusted to the amount of solids in the fluid, which reduces wear and tear on the pump and cleaner keeps the tanks. It also helps reduce downtime.
* Independent electrical heating system.
* Fluid transfer pumps high horsepower: Most companies use pumps 5 HP (horsepower). Reform using pumps of 10 HP, so it reduces the downtime that results from an overloaded motor wearing out.
* Injection Pumps electrochemical double head: Most companies use a pneumatic system that works with nitrogen or propane.
* Tornado Pilot System.
* Vent Fireplaces.
* Multiple venting Kelly 2 “2-5K throttle bypass circuits: dual choke manifold to purge the drill string. You can also purge from the separator directly to the fireplace or the lower fluid line.
Multiple drilling with rotary valves 4 “5K and double bypass choke 4.”
* Dual Valve Pressure Release: If the system has too much pressure, there is a security system at such risk.