Increasing Hydraulic Fracturing Success Ratio through Friction pressure management

Abstract

Hydraulic fracturing operation requires highpressure system to open the fracture in formation and delivers a number of proppant to be placed in. It has to counter minimum in-situ stress of formation, its tensile strength and friction pressure along the tubing (fracturing string) and near wellbore. Based on hydraulic fracturing job statistics in KS field, friction pressure is consuming up to 70% of the total pressure system. This huge number has to be managed to prevent operational problem in the execution and ensure that treatment designed can be delivered properly to increase the success ratio of the oil production result.

Evaluation of previous hydraulic fracturing job concluded that friction pressure along the tubing and near wellbore affect to the high surface treatment pressure and frequently close to the kick off pump pressure. Thus, pumping rate and maximum proppant concentration have to be limited and the fracturing fluid type also has to be adjusted. Therefore, some efforts have been established to decrease the friction pressure such as changing packer type that allowed increasing the tubing size but still fit to the current completion and changing the perforation method from explosive gun to the non-explosive abrasive jetting.

The results are very promising and affect to the total system pressure. By changing the packer type, it’s allowed to increase tubing diameter so that the friction in the tubing decreased to onethird of the previous tubing friction. The near wellbore friction decreased to one-fourth by changing the perforation method. These significant decreases of friction pressure yield the lower surface treatment pressure. Thus, fracturing treatment can be optimized to increase oil production. Moreover, the chance of early screen out can be minimized.