Sealing Aluminum Foil Caps to Plastic Bottles

THE LAB at Ambrell tested a cap sealing application for a client. It involved sealing a 1.5” (38.1 mm) diameter cap with foil to a plastic bottle within one second. The target temperature for this cap sealing application was 250-300 ºF (121-149 ºC). THE LAB determined that an EASYHEAT^TM 2 kW, 150-400 kHz induction heating power supply with a single turn helical coil of rectangular tube would meet the requirements of the client. 

In production, the bottles pass under the induction coil in significant volume. For testing, a silicon rubber was placed on the coil and then the aluminum seal was placed on the silicon rubber and heat was applied for 0.5 seconds. Then, the bottle was placed on the aluminum seal and pressure was applied causing the aluminum to seal to the plastic bottle. This met and exceeded all of the client's objectives. 

Speed (heating time) was important to this client, and this solution exceeded their requirements. The speed enables them to meet and exceed their throughput requirements for production. Induction is also highly repeatable, which is particularly important for a high volume heating process such as this cap sealing application. Finally, the coil design proved to be versatile and allowed for a number of production set ups, which was also important to the client. 

Visit our cap sealing page to see numerous induction brazing applications assessed by THE LAB at Ambrell. And, if you have an application you'd like tested, contact THE LAB to take advantage of complimentary induction heating application testing. You can even leverage Virtual Lab Service, where you can experience lab testing live from the comfort of your home or office.