A METHOD FOR TRANSVERSALLY SEALING A TUBE OF PACKAGING MATERIAL USING AN ULTRASONIC SEALING DEVICE, AN ANVIL AND AN ULTRA-SONIC SEALING DEVICE

摘要

A method (800) for transversally sealing a tube (116) of packaging material (102) using an ultrasonic sealing device (121), said method comprising placing (802) a transversal sealing section (112) of the tube (116) between a sonotrode (118) and an anvil (120) comprising a ridge (600, 700), wherein the transversal sealing section (112) of the tube (116) comprises a first two-layer sub-section (212), a three-layer sub-section (214) and a second two-layer sub-section (216), transmitting (804) ultrasonic acoustic vibrations, having a frequency (f) and an amplitude (A), from the sonotrode (118) into the transversal sealing section (112), thereby causing heat generation in the paperboard (104) in turn causing the plastic foil (106) in the transversal sealing section (112) to melt, and pressing (806) the tube (116) together between the sonotrode (118) and the anvil (120) by a pressure (P), thereby resulting in that the plastic foil (106) of the transversal sealing section (112) bond such that a transversal sealing (124) is formed, wherein the ridge (600, 700) of the anvil (120) comprises a first two-layer sub-section (602) for receiving the first two-layer sub-section (212) of the tube (116), a first two-or-three layer sub-section (604) for receiving the first two-layer sub-section (212) or the three-layer sub-section (214) of the tube (116), a three-layer-sub-section (606) for receiving the three-layer sub-section (214) of the tube (116), a second two-or-three layer sub-section (608) for receiving the three-layer sub-section (214) or the second two-layer sub-section (216) of the tube (116), and a second two-layer sub-section (610) for receiving the second two-layer sub-section (216) of the tube (116), wherein the ridge (600, 700) has equal height (H) in the first two-layer sub-section (602), the first two-or-three layer sub-section (604), the second two-or-three layer sub-section (608) and the second two-layer sub-section (610), wherein a combination of the frequency (f), the amplitude (A), the pressure (P) and properties of the paperboard (104) is chosen such that equal temperature in the first two-layer sub-section (212), the three-layer sub-section (214) and the second two-layer sub-section (216) of the tube (116) is achieved.