Handbook-Oxygen Cutting By Machine

Cleaning. Because of their unique design high-speed orifices cannot be cleaned in the same fashion as their

cylindrical counterparts. The operator must be made aware of the differences in geometry and cleaning procedures to prevent him from accidentally destroying the high-speed orifice. If ignorant of the differences the operator may force a cleaning wire, which fits into the expansion exit but that is too large to fit the throat, thinking that there is an obstruction up in side since the wire will only penetrate part way. This may destroy the expansion taper. Operators have been known to completely file away the inside geometry of high speed nozzles with ridged cleaning wires believing they were cleaning the nozzles when in fact they were destroying them beyond repair. Following the brief instructions inside Oxweld cleaning kit P/N 755FOO, the operator is instructed to insert the appropriate tapered tool (small for nozzles up to no.2, large for nozzles above no.2) into the expansion chamber with slight inward pressure. The tool should then be rotated until it turns smoothly. After removing the tapered tool, the largest wire that will comfortably fit completely through both the expansion taper and the throat should be slid in and out of the orifice several times to remove any debris. This will generally return the performance to expected levels. NOTE: If the proper cleaning kit can not be located for the expansion chamber, a simple round wooden toothpick can be used as a cleaning tool without damaging the nozzle. In the event the nozzle does not perform as expected, one final operation that will usually improve performance still further is a very light 90 degree included angle chamfer at the exit of the expansion chamber. This can be performed using a 90 degree countersink which is commercially available at your local hardware store. The recommended tool is a 1/4” or 3/8” single or three flute cutter. In using the cutter it is hand held against the exit of the expansion chamber and rotated gently to provide the slightest chamfer. This will remove any remaining burrs, slag, etc. and provide a smooth transition between the expansion chamber and the face of the nozzle. Continued on next page...