Gasket dispensing describes the extrusion of a viscous fluid that, upon curing, creates a seal with elastomeric (rubber-like) qualities. After cure, when a mating surface is applied, the joined parts typically meet some requirement for a barrier against liquids or gasses.
If the parts have been assembled prior to the compound curing, the gasket is more appropriately considered a seal and is by nature a one-time-use application. If the gasket compound is cured prior to assembly, that assembly in theory can be disassembled and reassembled throughout the life of the product.
Some common gasket compounds are RTV silicones, UV cure silicones, UV cure acrylates, UV cure polybutadienes, two component polyurethanes, two component silicones, and solvent cure systems.
Form In Place Gasketing
Using a robotic dispensing system to form such gaskets is commonly referred to as Form In Place gasketing (FIP), this process avoids the cumbersome aspects of handling and placing cut gaskets and affords the flexibility of many variations without having to inventory cut gaskets.
Classical gasket dispensing solutions include key process control elements such as needle tip calibration to ensure dispense tip location, height measurement (tactile, laser, or ultrasonic) to rule out part height errors, temperature control to lock in consistency, vision for part location and quality verification, and the software tools that make these elements work together effectively.
Standoff Foot Dispensing
New Precision Technology has developed a new standoff foot dispensing technique designed to deal with part height variation as a production issue. With standoff foot dispensing, we rotate the part, preventing potentially messy dispense valves from being complicated with rotational hardware. This technique lends itself to precision gasket formation for fuel cells, LCD screens, display terminals, and any flat structures requiring precision gaskets or adhesive seals.
Adhesion and Bonding
Adhesion promotion, resistance, and control is a crucial element of successful bonding, sealing, and gasketing operations. There are occasions where an application needs the most aggressive bond possible and other applications that require less aggressive techniques. Ultimately, the bond strength only needs to be as strong as the weakest bonded surface. There are many methods of adhesion promotion and all of them have their strengths and weaknesses:
Over the last two decades of dealing with adhesive, sealant, and gasket applications, New Precision Technology has implemented all of these processes and more, including:
- Flame treatment
- Corona or plasma treatment
- Solvent etch treatment
- UV “bedding” materials
- Soda or Sandblast etc
- Adhesion promotion chemistries
New Precision Technology, Inc. is a leader in affordable standard and semi-custom automated systems. To learn more, give us a call at 412-596-5948, or visit our Contact Us today.