Cord Dispersal

A proven and guaranteed solution to the

problem of cat scratch cord.

Cord Dispersal Systems

The PSR Cord Dispersal System is a guaranteed solution to the problem of cat scratch cord. We guarantee that if a client is not satisfied with the reduction in cat scratch cord following installation, we will refund the cost of the equipment and remove it at our expense.

Having installed over 240 Cord Dispersal Systems, we have never been asked to act upon our money back guarantee.

Key Features

  • Uses twin, counter-rotating, over-lapping paddle type stirrers.
  • Guaranteed solution to the problem of ‘Cat Scratch’ cord.
  • Aids the removal of residual colour streaks after colour changes.
  • Improves glass thermal homogeneity.
  • Can be installed on-the-run with minimal loss of production.
  • Does not require the installation of a special ‘drain channel block’.
  • Stirrers need only be used when cord is present.
  • No loss of production or cost of waste glass associated with continuous use of a drain.
  • Can be installed with pre-existing drains.
  • Can be used with submersed heating electrodes.
  • Stirrer life typically 6-12 months (based on use of PSR refractory stirrers).
  • ‘Pull-out’ design allows easy stirrer replacement and mechanism maintenance over the forehearth platform.


‘Cat Scratch’ cord is a visual defect found in many glass making operations and particularly in blownware and glass container production. Its source is the exudation of glassy phase material from the fused cast refractories in the melting end of the furnace. Due to its different viscosity characteristics as compared to the parent glass this cordy material gradually sinks to the bottom of the furnace and is drawn down the distributor and forehearths depending upon tonnage and temperature, appearing as a line or series of lines like the scratch of a cat’s claws on the surface of the glass product.

PSR’s Cord Dispersal System is a proven method to eliminate this problem and comprises twin counter rotating paddle type stirrers installed in the forehearth equalising section. The system is so effective that every installation comes with a money-back guarantee*. If the client is not satisfied with the degree of improvement in the visual appearance of ‘cat-scratch’ cord PSR will remove the equipment at their cost and refund the cost of the equipment to the client.

In addition to the removal of ‘cat scratch’ cord the stirrer systems have been found to remove colour streaks, in particular following furnace colour changes, and has been installed specifically for this purpose with the usual money back guarantee included. The stirrer systems also have positive effects on the glass conditioning, improving the spout entrance glass temperature homogeneity by typically 4-5%.

Each stirrer system is designed and configured to suit the existing forehearth configuration to provide the best solution possible to the particular problem. The stirrers are either installed in an existing opening in the equalising section superstructure refractories, or if an opening does not exist, the superstructure refractories can be designed and supplied by PSR and installed hot during an extended job change or other machine stoppage.

It is our experience, with over ten years of successful installations, that gives us the confidence to guarantee the results.

* guarantee subject to technical appraisal following receipt of full technical details from client.

Amber bottle with flint colour streak

Cat Scrat Cord

Bottle with typical cat scratch cord