The Theory Of Ultrasonic welding sealing
We desire that products meet the water, airtight function, positioning and ultrasonic fuse is one of the important key to success, so in product design, such as orientation, texture, flesh thick, corresponding than patients with ultra sonic fuse has absolute relationship.At the request of the general water, air, guide fuse height should be in the range of 0.5 ~ 0.8 m/m (depending on the product thick meat), such as less than 0.5 m/m, to achieve the function of water tightness, in addition to the location setting to very standard, and meat more than 5 m/m thick, otherwise the effect not beautiful.General water airtight products its positioning and ultrasonic fuse way is as follows:
Oblique type: suitable for water tightness and welding of large products, contact Angle = 45 °, x = w / 2, d = 0.3 ~ 0.8 mm is preferred
Ladder pointed type: suitable for water tightness and prevent outer convex or method of crack, the Angle of the contact surface = 45 °, x = w / 2, d = 0.3 ~ 0.8 mm is preferred
Peak valley pointed type: suitable for water tightness and high strength welding, d = 0.3 ~ 0.6 mm inside of the contact surface height h in accordance with the shape and size have change, but h about around 1 ~ 2 mm specified above three for water tightness ultrasonic fuse design method.
Improper welding conditions
Resolution:
Products for ultrasound cannot reach water, air, in addition to the ultrasonic fuse, fixture positioning, such factors as the product itself outside, ultrasound conditions set is also a main reason.We hereby further explore another reason lead the water airtight weld (welding conditions), when we implement ultrasound welding operations, pursuing efficiency quickly is the most basic goal, but also often overlooked by its efficiency of essentials, we will from agent for the following two conditions:
A, decreasing speed, buffer fast: the formation of the speed, the dynamic pressure and acceleration of gravity will be to fuse ultrasonic flattening, make lead fuse cannot play to the role of the guide melting, weld formation of illusion.
Second, welding time is too long: plastic products for long time to receive the heat energy, not only make the material of plastic melt, which causing more plastic organization coking phenomenon, produced sand hole, water or gas is the sand hole infiltration.This is the general production technology is the most difficult to find.