Ultrasonic welding processing parameters

Important processing parameters in ultrasonic welding are weld time, (the time vibrations are applied), weld pressure or force, hold time (the time allowed for cooling and solidification after vibration has ceased), hold force, trigger force (the force applied to the part before ultrasonic vibrations are initiated), power level, and amplitude of vibration. The horn must be properly... 

After the cause was identified, all welding seams, not only those directly affected, were removed on site under extremely difficult confined conditions and rewelded using improved welding parameters. This process took approximately 4.5 months, and was completed in accordance with a schedule drawn up for the operation. Ultrasonic tests shortly after repair and recharging with sodium and one year later showed no evidence of cracks. An examination of the complete plant for similar evidence showed that the cold trap vessels were also affected. However repair work on these was very much easier as disassembly and reassembly were relatively simple and repairs could be carried out in the workshop. 

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