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(copyright: Flame Spray Technologies)
What is thermal spraying?
HVOF (high velocity oxygen fuel) and plasma spraying are two of Flame Spray Technologies’ main coating application processes.
In HVOF, a liquid fuel such as kerosene or ethanol is mixed with oxygen and ignited to combustion. Metal or carbide powders are injected into the hot combustion gas stream and jetted with high velocity onto a substrate to be coated.
In plasma spraying, an electric arc adds energy to an argon gas stream which gets ionized and carries molten metal or ceramic powders to a substrate. Flow control plays an important role to control the supply of liquids or gases to these processes.
Application requirements
Supply of a constant gas or liquid flow to a thermal spray process determines the quality and thickness of the coating. Therefore, a high accuracy and reproducibility of the flow instrument is required. As calibration is conducted by Flame Spray Technologies as part of their service package to customers, the control stability and calibration accuracy are important aspects as well.
Important topics
Important topics
Easy fit of flow meter in the control cabinet
Calibration enables quality assurance
Training and advice on calibration
Process solution
Flame Spray Technologies uses the ‘OEM’ version of the ES-FLOW ultrasonic flow meter in their HVOF thermal spray equipment to supply liquid kerosene or ethanol to the process. The accuracy of the ES-FLOW fits well with the current application. This ultrasonic flow meter can measure and control liquids independent of fluid density, temperature and viscosity at affordable costs. The instrument controls a pump to obtain the desired process pressure. In addition, an Bronkhorst EL-FLOW Select thermal mass flow controller is applied to supply the oxygen.
In this case the ‘OEM’ model of the ES-FLOW without display has been chosen, to benefit from the rectangular shape and compact design to easily fit into the control cabinet of the spray equipment. The ultrasonic flow meter is connected to the customer’s operating system via PROFINET.
Control of the coating application process guarantees the quality of the coating, with thicknesses even smaller then a millimeter. To that end, calibration of the thermal spray equipment and its components is very important. Flame Spray Technologies includes calibration and maintenance of their equipment on-site. To calibrate the Bronkhorst flow instruments in the field, they use robust mobile calibration units from Bronkhorst. Flame Spray Technologies employees are trained in using these mobile calibration units by the training department at Bronkhorst headquarters in the Netherlands. To measure the thickness of the sprayed layers, Flame Spray Technologies has its own lab.
“To calibrate the flow instruments in the field, we use the mobile calibration units from Bronkhorst. Our employees are trained at Bronkhorst headquarters in using these mobile calibration units.”
Recommended products
ES-FLOW
Ultrasonic volume flow meter for any liquid including controller output
For 0...1500 ml/min
Accuracy ****
Versatile flow instrument, suitable for any liquid
Straight tube, therefore an intrinsic hygienic instrument (with optional 3-A certification)
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EL-FLOW Select
Lab-style Mass Flow Meter/Controller for gases
For 0.014 mln/min - 1670 ln/min
Accuracy ****
Best selling all-rounder for diverse applications
Suitable for pressures up to 400 bar
View range
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