Adhesive Dispense

Category: Surface Mount

Description: The automated application of an adhesive to the PCBA. This can be done by an in-line surface mount (SMT) machine which dispenses mechanical (e.g., “Loctite®”) or thermal (e.g., “Zymet”) adhesive to the surface of the PCB prior to component placement.(Also see Adhesive Staking and Adhesive Underfill.)

Major Cost Drivers -- PCBA Adhesive Dispense

Adhesive Dispense Process Time is a sum of the time to load the Printed Circuit Board (PCB) into the machine from the input conveyor, move the PCB to the lock position in the machine and clamp it down, look at the fiducials on the PCB, purge the solder paste from the nozzle and calibrate if required, deposit paste dots onto the PCB, and unload the PCB from the solder jetter and output rail.

Process Time = (Load Time + Fiducial Check Time + Adhesive Dispense Time + Unload Time) / Panel Quantity

Load Time = Adhesive Dispenser Load Time

Adhesive Dispenser Load Time = (Machine variable)

Fiducial Check Time = (Machine variable)

Adhesive Dispense Time = Dot Count / Dot Deposition Rate

Dot Count = Chip Dot Count*Qty SMChipComponents + Integrated Circuit Dot Count* (Qty SM Integrated Circuit Components + Qty SM Fine Pitch Components)

Chip Dot Count = (Machine variable)

Integrated Circuit Dot Count = (Machine variable)

Dot Deposition Rate = (Machine variable)

Unload Time = (Output Conveyor Length/Output Conveyor Speed) + Adhesive Dispenser Unload Time

Output Conveyor Length = (Machine variable)

Output Conveyor Speed = (Machine variable)

Adhesive Dispenser Unload Time = (Machine variable)

Load Time is the time to load the PCB into the machine input conveyor from the output conveyor of the previous machine (Screen Printer, Solder Jetter, or Solder Paste Inspection).

Fiducial Check Time is the time to look at the PCB alignment marks (fiducials).

Adhesive Dispense Time is the time to dispense adhesive onto PCB based on Dot Count (as specified in the component BOM) and the Dot Speed of the machine.

Unload Time is calculated from the machine unload time and the length and speed of the conveyor after Adhesive Dispense.

User Inputs – PCBA Adhesive Dispense

N/A