Customer’s Challenges

One of the leading companies in the personal care product manufacturing industry in Vietnam is facing pressure to increase productivity, ensure consistent quality, and optimize operational costs due to the growing consumer demand.
Among the key production stages, the manual pump cap tightening process for products like shampoo, body wash, hand soap, dishwashing liquid, etc., is one of the most limiting. Manual tightening slows down production, leads to inconsistent torque, which can cause product leakage, affecting brand image and consumer experience. Additionally, the inspection and removal of defective products are not optimized, resulting in increased costs and higher defect rates.
Moreover, the company has to handle a large variety of product types, with different bottle sizes and pump types, making automation complex. This complicates the synchronization of the production line, requiring flexibility and reducing waste when switching between product SKUs.

Customer Requirements

• A total of 30 SKUs corresponding to 10 different pump types need to be processed on the same production line.

• Maximum speed requirement: 150 products per minute (PPM), in line with the overall production pace.

• Flexible format change capability with quick changeover times when switching product lines.

• Consistent torque application, precise control of defective caps or mismatched pumps.

• Integration of quality control cameras to automatically remove defective products.

  

ETEK’s Solution

In response to the challenges faced, ETEK proposed and implemented a comprehensive automation solution for the pump cap tightening line. Based on the specific requirements for speed and precision, the system was designed with a maximum capacity of up to 150 bottles per minute. The line integrates various modern technologies, including: a pump feeder system, return conveyor for defective pumps, robot arm for gripping and positioning the pump caps, top-down tightening mechanism, and a camera system for precise tightening verification. Additionally, non-compliant products are automatically removed through an intelligent removal mechanism, minimizing defects and risks in the final stages of the production line.

1. Pump Feeder:
   The pumps are fed into the system via a vibrating hopper, ensuring proper orientation of the pump heads before transferring to the conveyor. This mechanism ensures stability and continuity of the pump input flow.

2. Return Conveyor for Pumps:
   Defective or unused pumps are returned to the feeder system via the return conveyor, reducing waste and enabling automatic reprocessing.

3. Tracking Conveyor:
   The conveyor system is equipped with sensors and counters to precisely track the position of each bottle on the line. This allows for smooth synchronization of subsequent operations.

4. Input Verification Camera:
   Industrial cameras are installed at critical positions to check the status of the bottles (whether they have a cap, whether they have a pump), and to remove defective bottles before they enter the installation area.

5. Pump Lifting Robot:
   The intelligent robot is capable of identifying and grabbing the correct type of pump for each product according to the SKU code. The robot arm operates quickly and accurately, ensuring proper positioning of the pump on the bottle.

6. Pump Cushioning via Conveyor and Return Pumps:
   After the pump is correctly positioned, it is temporarily held in the transfer area to synchronize the operation with the tightening robot. Incompatible pumps are automatically returned to the hopper.

7. Pump Transfer Mechanism:
   The transfer mechanism pushes the pump into the correct position on the bottle mouth, making it easier for the subsequent tightening step.

8. Pump Tightening Robot:
   The pump tightening robot is specially designed with adjustable torque settings for different types of pumps, ensuring just the right fit without causing damage. The top-down tightening mechanism, along with a screw-turning device, ensures precise and uniform operation.

9. Post-Tightening Bottle Inspection:
   After tightening, a second camera system checks the accuracy of the pump cap position: misalignment, loose, or skewed caps are detected and removed. Non-compliant products are automatically pushed out of the line via the automatic removal conveyor, ensuring that only compliant products proceed to the next stage.

Results Achieved

The automated line has delivered significant improvements. Production speed has increased substantially compared to the previous manual method. The cap tightening quality is consistent, with no more misaligned, loose, or leaking caps. The defect rate has been greatly reduced, thanks to the automatic inspection process, saving time and costs on final inspections. Moreover, the workforce required for this process has been optimized, as most of the steps are now handled by the control system and robots.