Knit Line Techniques

In cure-in-place (CIPG) and form-in-place (FIPG) gasketting applications, the gasket creates a seal used to protect critical components from air, dust and moisture intrusion, prevent leaking and dampen vibration. Achieving a good knit line can help to eliminate voids and ensure bead fusion to deliver a reliable seal.
 

Determining the appropriate knit line dispensing technique is an important consideration in dispense system programming and set-up. Several knit line techniques include the overlap, parallel pass, butt joint and sloping overlap.
 

Programming of the robotic dispensing system can also play a critical role in achieving bead path application requirements. Depending on the part complexity and axis, adjustments to the automation motion can help optimise the dispensing process. Several automation motion techniques include the rake motion, traditional motion, reverse rake and reverse rake and brake motion.

In CIPG and FIPG, knit line dispense techniques and automation motion techniques play a critical role in proper bead dispense and achieving the desired knit line. In addition, here are some other important considerations:

• Rheological properties of the material
• Material viscosity
• Temperature
• Bead profile and functionality
• Dispense valve sealing technology
• Dispense parameters
• Equipment fixturing
• Substrate design and complexity