Why is the welding quality of ultrasonic welder unstable?

The quality of ultrasonic welding cannot be stable, the main factor is that the output power is unstable, resulting in the inability to form stable frictional heat energy. So why is the welding power output unstable?

The Weldment and Welding Structure Design

First of all, when the product is ultrasonically welded, from the viewpoint of planning and design, the stronger the machine output power, the smaller the expansion ratio relative to the horn is designed. On the contrary, the smaller the output power of the machine, the larger the expansion ratio of the horn is designed. This is not to emphasize that the output power of the ultrasonic welding machine should be large, but to give the most suitable environmental operation when performing ultrasonic welding on some plastic products. When designing ultrasonic welding products, engineers will also evaluate the conditions: 1. Product quality requirements and functional standards; 2. Functions of existing ultrasonic welding equipment; 3. Ultrasonic energy director and material that determine product design. If the planning and design are unreasonable, it will affect the output power of ultrasonic welding.

Second, consider the factors of air pressure and voltage. Since the air compressor usually sets the air pressure in the air storage cylinder to be lower than 2-4kg, it will automatically inflate and fill, which is the cause of the error. When the air pressure source reaches the welding machine through the pipeline, due to the fast welding speed, the air pressure of the first ultrasonic welding and the air pressure remaining in the pipeline for the second or third time will also form an error, which will form periodic or non-periodic quality changes. The voltage is the output of the power company and is used by millions of people at the same time. The unstable voltage will cause the output power to be too high or too low. Such variables of air pressure and voltage will indeed cause changes in the output, which will affect the precision quality of the ultrasonic welding.

How To Solve The Problem of Welding Unstable?

Structure Design
Voltage Unstable
Air Pressure Unstable

If your product requires high welding quality, such as the product requires the welding accuracy to reach 0.02mm, or the welding energy director fusion condition needs to be more than 90%, the design engineer must be familiar with the following conditions: 1. Ultrasonic welding equipment; 2. Products need to be welded 3. Familiar with the corresponding relationship between ultrasonic welding and plastic fusion, and then give a reasonable design.

When the voltage is unstable, and the voltage will cause the output power of the ultrasonic welding machine up and down, in this situation, add voltage stabilization equipment as much as possible.

When the air pressure is unstable, if a large ultrasonic welding machine is used to weld smaller products, you can try to replace a smaller cylinder, or add an independent air compressor for the ultrasonic welding machine.