Page 60 - PCMI Journal December 2021

Maintenance Tips For PCM Etching Equipment
Kirk Lauver, Marketing and Customer Lab Manager, Chemcut Corporation, US
12/6/21
Maintenance Tips For PCM Etching Equipment Nozzles And Nozzles Maintenance
• Etching machines use either full cone or fan nozzles
• Spray angle and flowrate are selection parameters of both types
• Chemistry issues (scales and precipitates) can cause for many nozzles issues
• Improper cleaning and installation can damage nozzles and degrade the etching performance
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Maintenance Tips For PCM Etching Equipment Nozzles And Nozzles Maintenance
Nozzles Characteristics
• Nozzle Flowrate = K·P x X = 0.5 for Fan Nozzles and 0.46 for Solid Cone
• Manufacturer’s ratings are typically given at 40 psi (2.75 bar) with water.
• Nozzle Flowrate = 1/(Sp. Gr.)0.5(1 gpm with water will be 0.85 gpm at 1.4 Sp. Gr.)
• Nozzles are the primary flow determiner, not the pump
• There is only one degree of freedom, either control the flow or the pressure, not both
• Reducing the pressure reduces the spray angle, below 20 psi the angle begins to narrow, especially for fan nozzles
Issue 138 December 2021 PCMI Journal 60
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