The utility model discloses an emulsified liquid nozzle which comprises an end cover and a step positioning rod; the step positioning rod is in threaded connection with the end cover; the emulsified liquid nozzle further comprises a nozzle jacket which is sheathed outside the step positioning rod; the nozzle jacket is a step-shaped hollow sleeve; a center hole of the hollow sleeve is a step-shaped round hole; and grooves which are internally and externally communicated are uniformly arranged on the surface of the periphery of the nozzle jacket, contacted with the end cover. In the application of the hole enlargement of a straight welded pipe, omnibearing spraying in 360 degrees can be achieved, in addition, a steel pipe and a cooling grinding apparatus can be fully lubricated, the lubricating effect of spraying is improved, the purpose of hole enlargement is achieved, meanwhile, the service life of a die is also prolonged.