In this blog post and Tech Bites video we outline solutions to achieve repeatable quality and productivity on horizontal flow wrappers and vertical baggers across all production shifts, multiple packaging machines, and different plant locations.
Refinements and Forming Set Designs that Boost Productivity and Package Quality
Optimizing packaging performance requires fine-tuning of the entire product flow process—from the way product is distributed into the measuring system through to the filled, sealed, and cut bag or pouch.
Symptoms of product flow issues on vertical baggers include downtime from product blockages and poor end seals and cutting problems due to product contamination of the sealing jaws and knife. Considered in isolation, as one-time incidents, each problem may only cause a relatively short period of downtime and a small amount of product and film waste. But when the cumulative impact of product flow issues is considered over time, the costs can mount.
When product flow issues grow to be chronic, and their costs are recognized, running speeds are sometimes reduced to the threshold where problems no longer regularly occur. In these cases the resulting reduced output levels may become embedded; the presence of a potentially solvable problem is masked, and opportunities to achieve full potential for output and package quality can be missed.
Fortunately, there are a number of refinements that can streamline the product flow process. Read more
When cutting problems occur on horizontal flow wrappers during a production run, what are the best procedures to get packaging lines up and running again and to keep them running? Minimizing downtime, producing consistent quality packages, and managing costs require a balanced approach that includes:
- Knowing which “quick-fix” adjustments will get knives cutting without causing additional problems and downtime. (Faster and easier is not always the best solution.)
- Broad-based, P3 Solutions that consider the entire packaging process to:
• Understand how each adjustment affects the whole system.
• Eliminate procedures that don’t work.
• Diagnose and correct the ultimate causes of problems. (Many issues stem from a combination of factors.)
• Implement solutions that help prevent cutting problems from occurring in the first place and help you Pursue Zero.
When Knives and Anvils Stop Cutting:
The following procedures can help to get knives cutting again or, if knives and anvils need to be replaced, to refine the installation process. In either case, these guidelines will reduce downtime and optimize long-term performance.
The first two parts of this series explored the potential problems created by end seal wrinkles and creases and ways to eliminate or reduce them on horizontal flow wrappers (Part 1) and vertical baggers (Part 2). In some situations wrinkles or creases are unavoidable, and, even without those issues, most packages have the inevitable transition between multiple film layers created by either a fin or a lap seal. This can make it more difficult to achieve quality seals, and attempts to do so can lead to additional issues:
• Excess pressure can easily crush or split the end seal.
• Overheating distorts the seal and can cause poor hot tack, where the film springs back open, or “moons,” before the seal can set.
The operating window for creating quality seals can be elusive, resulting in packages that leak or are distorted and either fail to protect the product or have little appeal to consumers.
This post reviews some of the detailed solutions in Greener Corporation’s Knowledge Center that will help you seal over extra layers of film at the end seal by refining the set-up and adjustment of crimpers, sealing jaws, and knives.
When end seal issues such as leakers or splitting occur, an important initial step is to determine where, and how often, the trouble shows up. For problems that occur inconsistently—perhaps leakers on every other package, or splits only on the top or trailing end seals of the package—you need to determine if the bad seals show up randomly or according to a pattern. Do the problems occur on every package? On both ends of the package?
Start out by collecting a series of packages produced by the machine during production conditions. Number the packages sequentially and mark the machine flow direction. If you are working on a horizontal wrapper with multiple crimpers, label each pair (ex: A, B) and mark each seal according to the set of crimpers it came from. Now you can trace the problem seals back to the place they occur.
Following is a list of procedures that will help you troubleshoot intermittent seal problems. You can find additional details by clicking on the links or images in each section: Read more
Set-up procedures for knives and anvils can vary according to the make and model of the packaging machine, knife adjustment style, and other factors. There are, however, some general principles that make these adjustments more effective and efficient, reducing downtime and parts costs.
♦ Optimize Knife Design
- Knives ground on a diagonal, or bias–whether they have a zig zag or a straight cutting edge–require less pressure to cut so they are easier to set up and typically last longer.
- Zig zag knives with smaller (more) teeth are also easier to set up and provide longer life.
♦ Set Up the Crimpers First
- Clearance and Pressure Adjustments required to create a good seal can impact the knife and anvil set-up.