Line changeover for an SMT pick-and-place machine involves system reprogramming, feeder replacement, conveyor and positioning table adjustment, and placement head replacement. The specific steps are as follows.
1. Reprogram the Pick-and-Place Machine System
Pick-and-place machine programming can be done manually or by computer. Low-end models often use manual teaching programming, while high-end models support computer-based programming. During reprogramming, parameters such as component coordinates, placement sequence, and nozzle type must be re-entered according to the new product requirements, and a new placement program file must be generated. After programming, a simulation run should be performed to verify that the program logic is correct and that there is no risk of collision.
2. Replace the Feeders for the Previous Product
Quick-release devices should be used where available to shorten feeder replacement time. These feeders use fast snap-on structures that allow installation and removal within seconds.
A modular changeover strategy can also be applied. Multiple feeders are mounted on an independent feeder carriage, and components are replaced in batches by swapping the entire carriage. For example, tape feeders of different widths such as 8 mm, 12 mm, and 16 mm can be pre-assembled on a dedicated cart and pushed directly into the corresponding position of the pick-and-place machine during changeover.
Component compatibility should also be checked. Confirm that the new component packaging format, whether paper tape, plastic tape, or carrier tape, matches the feeder specifications to avoid feeding problems that may lead to component rejection.
3. Adjust the Transmission Mechanism and Positioning Table
When the new board width differs from the current setting, the positioning table width must be adjusted. On program-controlled models, the adjustment can be completed automatically by entering the board width parameter. On manual models, the width adjustment handwheel is rotated while observing the scale until the target value is reached.
The conveyor rail spacing should also be checked to maintain a clearance of 0.5–1 mm from the board edge. For special-shaped boards, a dedicated fixture may be required on the positioning table to achieve accurate positioning. Hansheng Automation can provide custom-machined fixtures or positioning blocks according to customer drawings for such applications.
Positioning accuracy should be verified by running a test board. After placement, inspect the component position deviation with a microscope. If the error exceeds ±0.05 mm, the vision system needs to be recalibrated.
4. Replace the Placement Head
When the new component type exceeds the current placement head configuration, replacement is necessary. For example, 0201 components may require a high-precision head, while odd-form components may require a multi-function head. A general-purpose head may be switched to a high-speed head to improve IC placement efficiency.
High-end models support automatic head replacement under program control. After selecting the target head model in the operation interface, the system automatically completes nozzle exchange and vacuum parameter adjustment.
For manual replacement, the vacuum generator must be turned off first. The old placement head is removed with dedicated tools, and after the new head is installed, Z-axis height calibration and nozzle pressure testing must be performed. Care should be taken to avoid collisions that could deform the placement head. For non-standard head adapters or precision replacement parts used during changeover, Hansheng Automation can provide machining based on customer drawings.
5. Verification After Changeover
After completing the above steps, a first article inspection should be carried out, focusing on component polarity, placement height, and soldering quality. A changeover checklist is recommended, covering program version, feeder model, positioning parameters, and other key data to ensure the changeover process is traceable.
