Inspection of ultrasonic welding for thermoplastic materials joining

In manufacturing industries, inspection process is the most vital process in production line in order to certify the quality of the product. At the end of every production line, there would be one quality assurance section to do the inspection. Sometimes quality inspection is not just needed at the end of the production line, it is also needed at specific area or at the process where usually problem occurs that denotes to bad quality product. This phenomenon frequently occurs in joining thermoplastic materials which used ultrasonic welding. Ultrasonic welding had increasing popularity as it offers a continued safe operation, faster and also low cost as it able to join weld part less than one second. Despite of its advantages in joining parts, ultrasonic welding is one of process that needs a special care and its own inspection process since it leads to major reject products because of its bad quality welding. Conventional inspection for ultrasonic welding joining usually used a destructive testing method, for an example pull/ push test. This testing will brings to waste in time and material cost. In order to encounter this matter, non destructive testing using ultrasonic testing is used in this research. It is been done by detecting the signal of ultrasonic welding vibration during the ultrasonic welding process of thermoplastic materials joining. This obtained signal will then be analyzed to acquire the abnormalities within the signal which represents the defects between the joint, thus concludes the quality of the product.