The MAC Paste Prep System mounts between the paste mixing cone and the paster hopper. It crushes large oxide nuggets to around 0.5 mm (0.020 in) to help prevent line stoppages which occur when large oxide nuggets try to pass through the hopper and cause continuous strip or grids to tear or jam under the hopper. Furthermore, it makes the paste more uniform allowing a smoother surface on the plates as they pass the hopper. The system consists of a box frame, two hardened steel rolls and a drive to power the rolls.
Paste preparation starts with the paste dropping from the mixing cone into the MAC Paste Prep System. The paste passes between two counter-rotating rolls which crush nuggets that are around 2 mm (0.080 in) thick or thicker, depending what gap is set, as they pass between the rolls. The processed paste is scraped off the rolls and drops into the paster hopper. The maximum amount of paste the MAC Paste Prep System can process is dependent on the gap between the rolls and the maximum speed the rolls can run without losing the adherence between the paste and the rolls.
The MAC Paste Prep System mounts to the base of the cone feeder, which is mounted on a pivot so it can be rotated out away from the hopper to access for cleaning and rotating the hopper up. All control buttons are mounted on the main unit, including a variable speed dial.
The mounting brackets are custom designed and require specific dimensions of the lower section of the cone feeder and top of the hopper. Minimum vertical space between the top of the hopper and bottom of the lowest item on the cone feeder is 276 mm (10.88 in) although 317 mm (12.50 in) is recommended.
Gap Size Speed