System and method for gas drainage and outburst prevention in coal seam by drill-cut linkage of long drilling hole and high pressure water jet

System and method for gas drainage and outburst prevention in coal seam by a drill-cut linkage of long drilling hole and high pressure water jet are provided. The system comprises a drill bit(9),a pressure induction valve(8),a drill rod(7),a drill machine(5), a high-low pressure water delivery and rotation device(6),a high pressure pump(3) and a water tank(1).The pressure induction valve(8) is mounted on the front end of the drill rod(7).The drill bit(9) is mounted on the front end of the pressure induction valve(8).A nozzle(22) is arranged on the outside of the pressure induction valve(8).The drill machine(5) drives the drill rod(7) to rotate. Water in the water tank(1) is delivered to the high-low pressure water delivery and rotation device(6) by the high pressure pump(3), into the drill rod(7) through the high-low pressure water delivery and rotation device(6), and to the pressure induction valve(8) through the drill rod(7). In the process of withdrawal of drill, coal seam is cut by high pressure water, which achieves the drill-cut linkage, improving work efficiency. The cutting diameter of the system is more than three meters, which increases the gas exposed area to more than six times of a conventional gas exposed area, and increases the range of gas release to more than three times of a conventional range of gas release, solving the problem of gas drainage and outburst prevention in coal seam.