Dispensing Methods for Use with Clearweld Materials
| Dispense |
Principle of Operation |
Main Advantages |
Limitations |
EFD
Needle Tip
Dispensing |
• Pneumatic valve, with needle tip attached to its outlet orifice, controls the flow of liquid. |
• Technology is well known.
• Relatively inexpensive.
• Provides latitude if a part is slightly bowed in X- or-Y-Axis. |
• Difficult to control on perfectly flat surfaces.
• Variations in Z-axis can create problems. |
PDI
Microsolenoid |
• Pneumatic pressure is used to force fluid through a miniature valve that opens and closes at a very high rate. |
• Precise volume control.
• Precise location of depositions.
• Very small volumes can be dispensed accurately. |
• Line width is relatively narrow (1-3mm) unless multiple valves are used.
• Price can vary from relatively inexpensive to very expensive, depending on the precisions of the system. |
EFD
Spray Nozzle |
• Liquid is fed through an air cap attached to a pneumatic valve to create a spray mist. |
• Can cover a large area. |
• Overspray.
• Masking may be required.
• Small line size is difficult to achieve. |
Sono-tek
Ultrasonic
Spray |
• Piezoelectric device atomizes a liquid as it flows through a dispense nozzle to create a fine mist. |
• A wide variety of deposition widths are possible.
• Low maintenance nozzles, no moving parts.
• Low velocity, impingement and overspray are minimal. |
• More expensive than standard spray techniques. |
Potential Applications for Applications Systems
| Surface |
Conditions |
EFD Valve
741VSSCW |
PDI Micro-
solenoid Nano
Dispense System
|
EFD Spray
781SS |
Sono-Tek
Spray Nozzles |
| Ledge ? |
Less than 1mm |
Difficult |
No |
No |
Yes |
| |
1mm to 3mm |
Yes |
Possibly |
Yes |
Yes |
| |
Larger than 3mm |
Possibly |
Difficult |
Possibly |
Yes |
| Channel ? |
Less than 1mm |
Possibly |
No |
No |
Yes |
| |
1mm to 3mm |
Yes |
Yes |
Yes |
Yes |
| |
Larger than 3mm |
Yes |
Difficult |
Yes |
Yes |
| Flat Surface |
Line applied to a smooth surface ? |
Possibly |
Possibly |
Possibly |
Yes |
| |
Line applied to a rough surface ? |
Possibly |
Possibly |
Possibly |
Yes |
| |
Total surface coating for a large area |
No |
No |
Yes |
No |
| Tubing ? |
Outside |
No |
Yes |
Possibly |
Yes |
| |
Inside |
No |
No |
No |
Unknown |
| |
Capillary Tubes ? |
No |
No |
No |
Yes |
| Patterns |
Circular Patterns ? |
Possibly |
Yes |
No |
Yes |
| 3D Parts |
Uniform Surface |
Possibly |
Yes |
No |
Yes |
| |
Irregular Surface ? |
No |
Yes |
No |
Yes |
| Microfluidic ? |
Thin channels |
No |
No |
Yes |
Unknown |
| Precision |
Accuracy required |
No |
No |
No |
Possibly |
Note: Possibly indicates that it may be possible to use this technology, however it would be on a case-by-case basis.
Difficult indicates that the technology could be used, but there might be some difficulty and may detract from the application.
|