A study made on drilling well pressure control includes the control of blowouts which are not common but are expensive, and the control of gas kicks, which are common, in a minimum time at minimum cost.
Human factors, equipment and procedures have all been considered. These considerations were used to develop the means for the drilling crew to control the well. This report defines specific equipment, procedures and training requirements to achieve this goal. This means of well control has been designed for use by a trained drilling crew.
To drill deep-wells competitively, it has become necessary to drill with minimum mud overburdens. To realize the maximum economic benefit from this practice, correct well control must be emphasized and practiced since the frequency of well kicks will increase. Kicks while rotating on bottom are not necessarily, undesirable if handled correctly.
A properly trained drilling crew using the equipment and procedures described in this report will never allow an uncontrolled kick or a blowout. The equipment and procedures for providing drilling well pressure control have been developed. Training is the additional ingredient required for pressure control.
The drilling crew will control kicks using adjustable chokes, mud separator, proper blowout preventers and an automatic control panel. The automatic control panel is designed to be operated by a roughneck or a driller. This equipment package will allow control of the well by the crew before changing mud weight or calling a supervisor. The crew will take shut-in pressures and put the well on the choke by determining the proper drill-pipe pressure and putting this pressure into the automatic control. This operation will almost totally eliminate the high pressure hazard in well kicks.
Once the well is circulating on automatic control, the supervisor can be called and arrangements can be made to change the mud weight or to take any other necessary steps. While the well is circulating on automatic control, no additional reservoir fluid enters the well. The well is therefore controlled in a minimum amount of time and with minimum hazard and cost.
A training session within our company demonstrated the ease in teaching and operating this system. Gas kicks were generated and controlled by this technique in a test well. The technique and system. were well received by technical and field personnel.
Proper training of the drilling crews will provide better pressure control to the drilling industry. Training should be to develop the skill of handling the equipment involved and to provide detection of kicks. The early detection of kicks cannot be overemphasized. On each drilling crew, one man should be specifically assigned to observe pit levels and trip gains and losses.
The following recommendations are made to provide drilling well pressure control:
initiate training of drilling crews,
upgrade blowout preventer, choke manifold, and mud separator specifications,
equip drilling rig with all of the specified equipment, and
hold regular drills during the drilling operation.