Sealing Over Extra Layers of Film at the End Seal (part 4 of 4): Optimizing Crimper & Sealing Jaw Design

Matt Wojtech horizontal flow wrappers, sealing, vertical FFS baggers January 15, 2018crimpers, downtime, Dura-Therm, Easy Seal, flexible sealing face, flow wrapper, fractured end seal, heat, leakers, mooning, packaging film, pressure, projects, sealing jaws, sealing theory, vertical bagger

There is no one-size-fits-all solution for the design of crimpers and sealing jaws on horizontal flow wrappers and vertical baggers; they should be specified according to the packaging film, products, and conditions of your packaging operation.

This post, the last in our four-part series, reviews design options for crimpers and jaws. The optimal combination of serration patterns, materials, and special features can dramatically improve seal quality and productivity when sealing across extra film layers at the end seal.

Transitions on the end seal between varying thicknesses of film created by the fin seal, lap seal, gussets, and wrinkles make it more difficult to maintain the operating window necessary for quality seals:

Too little pressure leaves gaps, or leakers, at these transition zones.
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 at transition zones or “moons,” before the seal can set.

Package Quality Issues_vertical baggers_Greener Corp

The end results can be packages that fail to protect the product or have little appeal to consumers, as well as lost production time spent attempting to meet package quality standards.

Crimper and Sealing Jaw Design Options

Troubleshooting Intermittent Seal Quality Issues

Mark Green cutting, horizontal flow wrappers, sealing, vertical FFS baggers December 7, 2016backlash, cleaning, clearance, crimpers, Dura-Therm, Easy Seal, flexible sealing face, heat, kevlar scraper, leakers, pressure, seal quality, sealing jaws, serrations, temperature

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

Optimizing Knife and Anvil Set-Up on Horizontal Wrappers

Matt Wojtech cutting, horizontal flow wrappers September 21, 2016anvil, cleaning, clearance, downtime, Easy Seal, flow wrapper, heat, knife, pressure, shim stock, training

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.

Case Study: Packaging Material Cost Reduction

Matt Wojtech horizontal flow wrappers, sealing January 1, 2016anvil, collaboration, crimpers, Easy Seal, flow wrapper, fractured end seal, knife, packaging film, productivity, projects, seal quality, seal reduction profile

Project Goals

The corporate engineering department at a large, international company commenced a project to reduce material costs for a variety of products that are individually packaged on horizontal flow wrappers. Greener Corporation was invited to participate in a series of meetings that defined the project’s initial goals:

To reduce the cut-off length for each package by reducing the overall seal width, thus allowing the product envelope to remain unchanged.

To achieve material savings without degrading seal integrity or productivity levels.

To achieve a project payback period of twelve months or less.

Cleaning to Improve Package Quality & Productivity

Mark Green cutting, forming, horizontal flow wrappers, sealing, vertical FFS baggers March 31, 2015cleaning, crimpers, downtime, Easy Seal, flow wrapper, forming set, kevlar scraper, knife, seal quality, sealing jaws, serrations, vertical bagger

The newest video in Greener Corporation’s “Tech Bites” series demonstrates the benefits of proper cleaning procedures for crimpers and sealing jaws on horizontal flow wrappers and vertical baggers.