Even experienced users of forming sets can, over time, become conditioned to accept the hidden costs and preventable constraints of their packaging equipment. As with all waste, however, careful diagnosis of the root causes will lead to implementation of effective solutions.
One such root cause is forming tube misalignment. This can occur if the forming set has been accidentally mishandled and damaged or if the forming set has not been properly designed and fabricated in the first place.
With side-to-side misalignment one drive belt applies less pressure than the other, and as the film slides down the forming tube each side is subject to unequal tension. The belts wear out prematurely, increasing parts replacement costs and downtime. This misalignment can also cause the film to lose contact with the forming shoulder on one side, creating small but unsightly horizontal creases on the finished bag that reduce shelf appeal may compromise the film structure’s barrier integrity.
When the forming tube is misaligned front to back, inconsistent contact with the heater bar or band can cause distorted or open back seals. Twisted forming tubes can produce bags with graphics shifted to one side or bags that are twisted themselves—the top and bottom seals are not parallel to each other. Twisted tubes can also provoke belt wear issues.
The symptoms discussed here—premature drive belt wear, creased bags, poor back seals, off-set graphics, and twisted packages—indicate that your forming set may require repair or replacement. Properly designed and fabricated forming sets should allow for installation with minimal fuss and downtime—without compromising package quality—and should be consistent and interchangeable from order to order.
For a broader discussion of optimal forming set performance, please consult “The Hidden Costs of Average Former Sets,” a white paper published on the Greener Corporation and Kenray Forming Limited websites. For help diagnosing forming issues specific to your packaging operations, please contact Greener or Kenray directly.