Check valve for well stimulation

A method for regulating the injection of a stimulation fluid into a subterranean formation, comprising:

• arranging a base pipe within the subterranean formation, the base pipe having a check valve assembly arranged therewith, the check valve assembly having a valve body defining an inlet, one or more discharge ports, and a cylindrical passageway fluidly communicating the inlet with the one or more discharge ports, the check valve assembly further having a piston movably disposed within the passageway;
• magnetically-attracting the piston into engagement with a valve body seat defined in the passageway such that the piston is biased to a closed configuration that prevents fluid communication between the inlet and the one or more discharge ports;
• and
• injecting the stimulation fluid into the base pipe at a rate sufficient to induce the piston to move from the closed configuration to an open configuration where the piston engages a valve cap seat defined in a valve cap coupled to the valve body and defining an opening therein, the opening providing fluid communication between the cylindrical passageway and the subterranean formation, and
• wherein the stimulation fluid is injected at a rate sufficient to induce the piston to engage the opening and form a mechanical seal therewith.