What is your Pipe Size? Say, if it is a 8-12" line use one or more Guides at 4 to 6 diameters from the Nozzle. Again, depending on the size you can move it back and forth to get the best result and each guide not close than two diameters apart. It is a trial and error method in order to get the best result. Essentially you are eliminating or minimizing the moment vector at the nozzle.