System and method for interpreting drilling date

A method for determining potential drilling hazards in a wellbore, comprising:

• determining times at which a drilling system is conditioning the wellbore;
• measuring at least one of a parameter related to drill string rotation, a parameter related to drill string axial motion and a parameter related to drilling fluid pressure during the conditioning;
• generating a warning signal if at the at least one parameter exceeds a selected threshold during the conditioning.
• determininig a value of at least one of a difference between a maximum and a minimum measured torque, a variation in torque a maximum value of rotational acceleration and drilling fluid pressure variation each of a plurality of times the drilling system is conditioning;
• and
• generating a signal that the conditioning is substantially complete when selected ones of the value of the difference between the maximum and minimum measured torque, the maximum value of rotational acceleration and the fluid pressure variation drop below a selected threshold.

A method for determining potential drilling hazards in a wellbore, comprising:

• determining when a drilling system is static, wherein drilling fluid pumps are not operating and a drill string is not moving;
• during a period during which the drilling system resumes drill string movement and fluid pump operation following when the drilling system is static, measuring at least one of a maximum torque, a maximum hookload and a maximum drilling fluid pressure;
• and
• generating a warning signal if the at least one of the maximum torque, the maximum hookload and the maximum drilling fluid pressure exceeds a respective selected threshold.

A method for determining whether conditioning a wellbore prior to making a connection is substantially completed, comprising:

• measuring a length of conditioning time prior to each connection;
• measuring at least one of a maximum hookload, a maximum torque and a maximum drilling fluid pressure during a resuming drilling time after each connection time;
• and
• determining a minimum safe conditioning time from a correlation between the measured conditioning time lengths and the measured at least one maximum hookload, maximum torque and maximum drilling fluid pressure during a time of resuming drilling for each connection.

A method for determining a safe maximum value of a parameter related to speed of motion of a drill string during drilling operations, comprising:

• measuring a drilling fluid pressure;
• measuring at least one parameter related to speed of motion of the drill string along the wellbore;
• determining a relationship between the measured parameter and the drilling fluid pressure;
• and
• generating a warning signal when the measured parameter correlates to a drilling fluid pressure approaching a safety limit.

A program stored in a computer readable medium, the program including logic operable to cause a programmable computer to perform steps comprising:

• measuring a drilling parameter;
• correlating the measured drilling parameter to a depth in the wellbore at which selected components of a drill string pass;
• determining changes in the measured parameter each time the selected components of the drill string pass selected depths in the wellbore;
• and
• generating a warning signal in response to the determined changes in the measured parameter.

A program stored in a computer readable medium, the program containing logic operable to cause a programmable computer to perform steps comprising:

• determining times at which a drilling system is conditioning the wellbore;
• measuring at least one of a parameter related to drill string rotation, a parameter related to drill string axial motion and a parameter related to drilling fluid pressure;
• generating a warning signal if at the at least one parameter exceeds a selected threshold during the conditioning;
• determining a value of at least one of a difference between a maximum and a minimum measured torque, a variation in torque a maximum value of rotational acceleration and drilling fluid pressure variation each of a plurality of times the drilling system is conditioning;
• and
• generating a signal that the conditioning is substantially complete when selected ones of the value of the difference between the maximum and minimum measured torque, the maximum value of rotational acceleration and the fluid pressure variation drop below a selected threshold.

A program stored in a computer readable medium, the program including logic operable to cause a programmable computer to perform steps comprising:

• measuring a drilling fluid pressure;
• measuring a parameter related to a speed of motion of the drill string along the wellbore;
• determining a relationship between the measured parameter and the drilling fluid pressure;
• and
• generating a warning signal when the measured parameter correlates to a drilling fluid pressure approaching a safety limit.

A computer program stored in a computer readable medium, the program including logic operable to cause a programmable computer to perform steps comprising:

• measuring a conditioning time prior to each of a plurality of drill string connections;
• measuring at least one of a maximum hookload, a maximum torque and a maximum drilling fluid pressure during a resuming drilling time after each of the connections;
• and
• determining a minimum safe conditioning time from a correlation between the measured conditioning times and the measurement of at least one of maximum hookload, maximum torque and maximum drilling fluid pressure during a time of resuming drilling for each connection.

A computer program stored in a computer readable medium, the program having logic operable to cause a programmable computer to perform steps comprising:

• determining when a drilling system is static, wherein drilling fluid pumps are not operating and a drill string is not moving;
• during a period during which the drilling system resumes drill string movement and fluid pump operation following when the drilling system is static, measuring at least one of a maximum torque, a maximum hook load and a maximum drilling fluid pressure;
• and
• generating a warning signal if the at least one of the maximum torque, the maximum hook load and the maximum drilling fluid pressure exceeds a respective selected threshold.

A method for determining a maximum safe time in slips comprising:

• measuring a time in slips for each connection;
• measuring at least one of a maximum hookload, a maximum torque and a maximum drilling fluid pressure during a resuming drilling time after each connection time;
• and
• determining a maximum safe time in slips from a correlation of the measured time in slips to the measured at least one of maximum hookload, maximum torque and maximum drilling fluid pressure for each connection.

A computer program stored in a computer readable medium, the program comprising logic operable to cause a programmable computer to perform steps comprising:

• measuring a time in slips for each connection;
• measuring at least one of a maximum hookload, a maximum torque and a maximum drilling fluid pressure during a resuming drilling time after each connection time;
• and
• determining a maximum safe time in slips from a correlation of the measured time in slips to the measured at least one of maximum hookload, maximum torque and maximum drilling fluid pressure for each connection.