Kerf check and Nozzle Assembly Check
Orifice and nozzle tip are two consumable parts of the nozzle assembly. Their life is projected to be around 300 hours. Checking their condition is key to maintaining proper cutting. Kerf check aims to find out the condition of the nozzle tip; orifice stream shape check is a good indicator of the orifice health. If either parts are degrading, replacement is needed.
Required Tools
PPE (gloves, masks and eye goggles)
A caliper
Filler gauges/needle gauges/ feeler gauge/ pin gauges (if possible)
A Spare piece of material of interest.
Procedure
Kerf Check
1. Kerf is the width of material removed during cutting.
2. It depends on the material property and thickness.
3. If the kerf on the same thickness of the same material increases after extended operation, it is an indication that the nozzle tip of the nozzle assembly is degraded.
4. The kerf check can be achieved by slit method or square method.
5. In the slit method, a straight line is cut on the selected test material using WAZER Pro. Then a filler gauge set is used to find out the exact size of the slit on the top surface.
6. In the square method, a square of certain size is cut on the selected material using WAZER Pro. Then use a caliper to measure the dimension of the cut out part and the cut out blank. The difference is twice the size of the kerf.
7. For more detailed information, see the online instruction of how to measure kerf.
Orifice health check
1. The shape of the water stream generated by orifice is a good indicator of the orifice health.
2. Water stream rushing out from the complete nozzle assembly is re-shaped by the nozzle tip.
3. Thus nozzle tip needs to be removed to view the true orifice stream.
i. Remove the abrasive hose from the side of the cutting head.
ii. Move the cutting head to the upmost position, lock it in place, and unscrew the nozzle guard.
iii. Pull down the nozzle guard
iv. Pull down the plastic collar and nozzle tip.
v. go to Setup & Maintenance > Maintenance > Nozzle Purge.
vi. Compare the stream to the videos shared in the online instruction
vii. A good orifice stream should be evenly distributed and focused.
viii. If you observed pulsating, exaggeratedly spreading or unevenly distributed streams, they indicate a bad orifice. Replacement is needed.