The two most popular techniques to weld fabric collectively are Radio Frequency (RF) and Ultrasonic welding.They both by transferring heat and pressure to create the bonds, but there are a slightly different between them.
Ultrasonic Welding Machine Working
Ultrasonic welding creates heat in an traditional way. It uses a horn (ultrasonic system) to apply pressure between two sheets of material, and then rubs them together really fast( generally 15000-40000 times per second) to create friction. That friction creates the heat that melt the two pieces of material together.Ultrasonic welding technology can be used for welding ultrasonic plastic ,fabric and ultrasonic metal welding and etc.
Following are the useful process parameters used in ultrasonic welding.
- Amplitude: Motion of horn at horn or part interface
- Weld time: Length of the time sonics are being activated
- Hold time: The time during which parts are held under the force after sonication
- Ramp time: Length of the time the sonic ramp up during the welding cycle
- Weld Force: The amount of force applied to the parts.
- Trigger force: Force at which sonics are being activated.
- Melt down/collapse: Amount of weld down during the weld.
- Mode: primary process variable which defines weld cycle, e.g. time, melt down, energy or peak power.
Radio Frequency Welding Machine Working
Radio Frequency welding is a bit more scientific.Like with ultrasonic welding, pressure is applied to the plastics materials, but instead of heat created through friction, a high frequency electromagnetic energy (radio waves) is used to fuse the materials together. The energy generated by this process causes the molecules in the material to vibrate, which creates heat and allows the plastics to fuse together.
RF welding is a fast process, does not require any special joint designs and produces cosmetically appealing welds. With this method of welding, the heating can be localized and the process can be continuous. RF welding creates a consistent weld, and is used in industries such as medical device manufacturing where a strong, leak-proof seal may be required. At Genesis, our RF welding services can weld very thin gauge (down to 0.001 inch) polymers from a tiny weld spot up to 82” by 42” in size.
Following are the useful process parameters used in RF welding
- Voltage: It refers to voltage needed at the electrodes
- Frequency: It refers to frequency of the applied Electric field
- Hold time: It is the time duration upto which parts are held under • force after sonication
- Weld force: Amount of force applied to part.
- Electrode separation: Initially it is the thickness of the materials; at the end of welding cycle it is the distance between the electrodes.
A good quality weld not only depends on the method used, but also on the chosen materials.