In an apparatus for mounting a spout 1 on a plastic film 2 fed longitudinally thereof and intermittently, the plastic film 2 is punched by a punch blade 6. An aperture is therefore formed in the plastic film 2. A carriage 8 is moved for a distance L corresponding to a space between the punch blade 6 and a seal head 9 and between a punch receiver 7 and a seal receiver 10. A spout 1 is inserted into the aperture. The spout 2 and the plastic film 2. are heat sealed with each other by the seal head 9.

A split bus assembly is provided for a heat-sealing machine. The split bus assembly includes a clamp with first and second clamp segments that abut each other in face-to-face engagement. The engaging surfaces or inner walls of the clamp segments may be coated with a nonconductive material so that the clamp segments are electrically insulated with respect to each other. A tab terminal may be defined at each inner wall, constituting a zone of exposed conductive material which is configured to engage a conductive tab of a heat-seal band during use. Biasing members such as a silicone spring may be arranged in the tool to facilitate ejection of the heat-seal band during a removal procedure. The tool may be cooled by way of cooling fluid that flows through passages in the bus bars.