Sealing Temperature Archives - Greener Corporation

How to Determine the Optimum Machine Speed on Flow Wrappers and Vertical FFS Baggers

Michael Wojtech — Sun, 25 Jan 2026 19:58:53 +0000

A Tech Bite from Greener Vice-President & co-owner Matt Wojtech

“The Tortoise and the Hare” and “Slow is Smooth, and Smooth is Fast” are just two of many adages promoting the advantages of a slower, steady pace for solving problems and accomplishing goals. Does this strategy apply to your packaging lines?

This Greener Tech Bite explains how you can use the seal range of your flexible packaging material to determine the optimum machine speed on your flow wrappers and vertical baggers.

Sealing Jaw Temperature Cycles

During steady production, sealing jaw temperatures dip as they transfer heat to the package and then recover. These temperature cycles typically range within a few degrees.

When product feed rate fluctuates and production slows or is interrupted, sealing jaw temperatures cycle more widely.

Setup for Maximum Machine Speed

Flow wrappers and vertical baggers are often set up to run at maximum speed, with the intent to increase output. To maintain seal quality with the resulting shorter dwell times, sealing pressure is increased just short of the point where seals are crushed or split.

Steady Production Rate

Temperature is set to the highest possible level that keeps temperature cycles within the packaging material’s seal range—the span between the seal initiation temperature and distortion temperature. The seal range narrows as machine speed increases and dwell time is reduced.

Variable Production Rate

With machines set up for maximum speed, any fluctuation in product feed rate that slows production creates wider temperature cycles that can exceed the seal range.

This results in damaged and distorted packages with poor seal integrity.

Downtime accumulates as operators stop the machine to clean melted packaging material and product from the sealing jaws and fin wheels.

Maximum vs. Slower, Steady Machine Speed

Let’s look at some examples that compare scrap rate, downtime, and output levels for a flow wrapper and a vertical bagger set up to run at different speeds.

Flow Wrapper

A. Setup for Maximum Machine Speed

In situation A, a flow wrapper is set up to run at the maximum speed of 300 packages per minute. Over a ten hour production run, the wrapper only maintains this top speed for a cumulative total of five hours, or half the run.

During the other five hours, machine speed ramps up and down and occasionally pauses as the product feed rate fluctuates. With the wrapper set up to run at maximum speed, sealing jaw temperature cycles frequently exceed the seal range, increasing the scrap rate and downtime and limiting production to an average of 200 packages per minute.

Potential total output for the run is 150,000 packages, but actual output is limited to 117,000 packages.

B. Setup for Slower, Steady Machine Speed

In situation B the wrapper is set up to run at 225 packages per minute, which provides a broader seal range to accommodate wider temperature cycles when the product feed rate fluctuates.

This machine speed is maintained for most of the ten-hour run, with low scrap and downtime rates, and 129,600 packages are produced.

**A: Maximum vs. B: Slower, Steady Machine Speed**

Setting up for and running at this slower, steady speed improves seal quality and produces higher actual output than the setup for maximum speed.

Vertical Bagger

**A: Maximum vs. B: Slower, Steady Machine Speed**

Similar outcomes occur on vertical baggers where the product feed rate fluctuates. The setup for slower, steady machine speed produces more packages with better seal quality.

Slow is Smooth, and Smooth is Fast

To optimize setup on your flow wrappers and vertical baggers, use seal range and temperature cycles to determine what machine speed produces the highest output and best seal quality.

For cold seal applications where temperature and dwell time are not issues, setting machine speed to the maximum product feed rate can still cause problems that decrease output, such as frequent starting and stopping, empty packages, and product registration issues.

Dura-Therm and XR™* Sealing Jaws

You can increase the optimum machine speed on your flow wrappers and vertical baggers by updating to advanced sealing jaw designs.

* patent pending

Dura-Therm sealing jaws and XR™* Serration Technology reduce sealing jaw temperature variation, resulting in narrower temperature cycles that provide two types of opportunities:

Increase Output

To increase production output, you can increase machine speed and still keep temperature cycles within your material’s seal range to maintain seal integrity.

Convert to Sustainable and Less Expensive Packaging Materials

With Dura-Therm and XR™* sealing jaws, you can convert to sustainable or less expensive packaging materials with a narrower seal range without reducing machine speed or seal quality.

Slower and Steady Wins the Race

Setting up your packaging machines for slower, steady production and updating your sealing jaws can optimize production output and quality.

For help determining your optimum machine speed, or to learn how Dura-Therm and XR™* Sealing Jaws can improve your results, contact Greener Corporation.

We provide integrated parts and technical service solutions worldwide.

The post How to Determine the Optimum Machine Speed on Flow Wrappers and Vertical FFS Baggers appeared first on Greener Corporation.

How the Structure of Flexible Packaging Materials Impacts Their Sealability

Michael Wojtech — Wed, 23 Jul 2025 16:10:26 +0000

A Tech Bite from Greener Packaging Technology Engineer Steve Tucker

This Greener Tech Bite explains how the structure of a flexible packaging material effects its seal range and ultimately determines maximum machine speeds.

We examine legacy technologies as well as today’s sustainable materials, and discuss how Greener’s new sealing jaw technology expands the seal range to increase production speeds and improve package quality on flow wrappers and vertical FFS baggers.

In previous Tech Bites, we’ve defined seal range as the difference between the seal initiation temperature and seal distortion temperature during the packaging process. We’ve shown that the seal range must be wide enough to accommodate the normal temperature cycles of the sealing jaws.

Flexible Packaging Materials

Polymer Type & Thickness

To explain the impact of flexible packaging material structure on seal range, we will focus on the type and thickness of both the core layer polymers and the sealant layer.

Laboratory Melt Point Spread

One of the more important polymer attributes is the melt point of the core layers, which varies significantly between polymer types. The higher the melt-point, the more resistant the material becomes to heat-related damage at high temperatures.

The sealant layer is designed to have a lower melt temperature than the core layers.

We can refer to the spread between the sealant layer melt point and the core layer melt point as the laboratory melt point spread, which relates only to theoretical temperatures, without respect to the packaging conditions required for the material to reach those temperatures.

Seal Range

Melt Point Spread is not quite the same as seal range, which is a bit more complex. Rather than looking solely at a material’s theoretical melt points, seal range describes the machine settings necessary to achieve those melt points.

A true seal range study will describe the relationship between sealing jaw temperature, dwell time, and force, and will ultimately determine the optimized settings necessary to maintain seal quality.

Laboratory Melt Point Spread vs Seal Range

The seal initiation temperatures and distortion temperatures of a material’s seal range are always higher than the laboratory melt points. The difference is a function of a material’s thermal conductivity and thickness, along with the available dwell time and force.

Thermal Transfer Efficiency (TTE)

The goal is to optimize Thermal Transfer Efficiency (TTE)—to reach seal initiation temperature at the sealant layer as quickly as possible, without heating the core layers to their distortion temperature.

Force, and the efficient distribution of that force, is the key driver of Thermal Transfer Efficiency.

Seal Range Factors

Dwell Time – Machine Speed

As machine speed increases and dwell time is reduced, the seal range narrows.

Flexible Packaging Material Thickness

Increasing a material’s thickness also narrows the seal range; the core layer distortion-point is raised, but the seal initiation temperature is raised even higher.

Temperature

Temperatures can be increased, but machine speed is limited by the need to keep normal sealing jaw temperature cycles within the seal range.

Flexible Packaging Material Structure

Compared to many other materials, polyester offers a broader seal range that enables excellent seal integrity even at high machine speeds.

Materials with a narrower seal range, including many sustainable structures, have often required slower machine speeds to maintain seal quality.

Increase Thermal Transfer Efficiency (TTE) to Expand Seal Range

Significant increases to the Thermal Transfer Efficiency of the sealing jaws can mitigate machine speed limitations. As Thermal Transfer Efficiency is improved, optimum heat will be transferred from the sealing jaws into the packaging material at a lower temperatures and/or in less time, allowing for a wider seal range that provides increased machine speed.

XR™* Sealing Jaws

Greener Corporation’s XR™* Sealing Jaws, utilizing unique serration geometry and Dura-Therm material, provide this increased Thermal Transfer Efficiency by distributing a machine’s existing sealing force more effectively.

Sustainable Materials & Difficult to Seal Packages

XR™* Sealing Jaws provide the broader seal range that can be especially critical with sustainable materials and difficult to seal packages, where the need for longer dwell times has previously created package quality and machine speed limitations.

Reduce Flexible Packaging Material Costs

Increased Thermal Transfer Efficiency can also maintain seal quality and machine speeds with thinner or less expensive sealant layers that reduce flexible packaging material costs.

Are you missing opportunities to expand your seal range to increase machine speed, improve seal quality, and reduce costs?

Contact Greener Corporation’s Technical Specialists. We provide integrated parts and technical service solutions worldwide.

The post How the Structure of Flexible Packaging Materials Impacts Their Sealability appeared first on Greener Corporation.

Optimizing Fin Wheel Performance on Flow Wrappers

Michael Wojtech — Sun, 26 Jan 2025 19:29:27 +0000

When poor tracking, slippage, and other problems occur on flow wrappers, fin wheel pressure or temperature is often increased to get the machine up and running again.

These adjustments, however, may only be a temporary fix that could cause more severe problems in the future.

This Greener Tech Bite presents a systematic approach you can use to:

Optimize Fin Wheel Adjustments
Troubleshoot Problems
Implement Preventative Maintenance

Follow these procedures to ensure consistent package quality and productivity.

Most wrappers utilize at least two, and often three, pairs of fin wheels. The first pair, typically unheated, works primarily to draw the packaging material tube forward through the wrapper. The second and third pairs seal the fin and guide the tube forward.

The same four steps can be followed to solve fin wheel problems and for preventative maintenance, which should be performed every six months.

Inspect
Check Bearings
Test Sealing Pressure
Check Adjustments and Design

1. Inspect

Begin by removing the cover plates and making a visual and physical inspection.

Damage, Wear, Sharp Edges

Rotate each pair of fin wheels and check the sealing surface for damage and wear. Make sure their top edges have not grown sharp from rubbing against the cover plate.

Clean

Clean any packaging material or product that has built up on the sealing surface.

Replace fin wheels that are worn, damaged, or that can’t be properly cleaned with a new, matched pair; never replace just one fin wheel.

2. Check Bearings

Even with new fin wheels, slippage and poor tracking can continue if the bearings are worn. Bearing failure is often caused by excess pressure and heat adjustments that were made to compensate for worn fin wheels.

Using protective gloves if the fin wheels are hot, grasp and try to rock each fin wheel backward and forward, between the product feed and the product discharge. Any freedom of movement indicates worn bearings that should be replaced.

3. Check Sealing Pressure

Fin wheel wear that was not detected during the visual inspection can still cause problems.

Bring the fin wheels to operating temperature, and engage each pair together with a doubled piece of packaging material between them.

If the material can easily be pulled out, make sure the tension between the fin wheels is within normal operating parameters. If pressure is too low, make corrective adjustments to increase it. If pressure settings are correct, the fin wheels are likely worn and need to be replaced.

Worn bearings will also yield this result, so be sure to follow step 2 before doing this test.

4. Check Adjustments and Design

If problems continue after following the first three steps:

Temperature

Make sure that fin seal temperature settings are within the proper range for your flexible packaging material. Excess heat causes slippage problems and can distort and even melt through the fin seal.

Tilt

Next, check the tilt adjustment of the fin wheels. Additional tilt, where the infeed end of the fin wheel is slightly higher than the discharge end, gives the fin wheels more “bite” and helps them draw the tube forward.

This tilt also pulls the material downward to create tighter packages.

Make this adjustment with care.

Too severe an angle can cause the fin wheels to rub against the cover plate and develop sharp upper edges that cut the package.

Gripper Grooves

If problems still persist, install fin wheels with gripper grooves for the first, leading pair. Gripper grooves provide extra tension to prevent slippage and tracking issues.

Dura-Therm

Some flexible packaging materials are poor thermal conductors, such as paper and some thicker structures.

For these applications, fin wheels made from Dura-Therm provide more consistent, responsive heat transfer to prevent temperature fluctuations that cause sealing and tracking issues.

Product Presentation & Package Formation

Problems that persist after following these troubleshooting steps are often caused by upstream issues.

Learn more from our post and video on Product Presentation and Package Formation.

If you’d like technical assistance with fin wheel or other packaging problems on flow wrappers or vertical baggers, contact Greener Corporation.

We provide integrated parts and technical services worldwide.

The post Optimizing Fin Wheel Performance on Flow Wrappers appeared first on Greener Corporation.

XR™* Sealing Jaws Improve Thermal Transfer Efficiency to Provide Better Seals, Faster

Michael Wojtech — Fri, 29 Nov 2024 19:15:52 +0000

What if a new, unique design for sealing jaws could provide better seals, faster than you thought were possible on vertical baggers and long dwell flow wrappers?

This Tech Bite explains how Greener Corporation’s XR™* Sealing Jaws dramatically improve Thermal Transfer Efficiency to:

Improve Package Quality
Increase Machine Speed
Run Sustainable Materials & Hard to Seal Packages
Reduce Flexible Packaging Costs

The Sealing Process

Seal Range and Temperature Cycles

The seal range for your packaging material and conditions spans between the seal initiation temperature and the distortion temperature. The seal range must allow for sealing jaw temperature cycles as the jaws transfer heat to the package and then recover, and for wider temperature cycles when production slows down or is interrupted.

Machine Speed

The effective seal range narrows as machine speed is increased and dwell time is reduced. Machine speed is limited by the need to keep normal temperature cycles within the effective seal range.

Thermal Transfer Efficiency

During the sealing process, Thermal Transfer Efficiency determines the dwell time required to transfer heat from the sealing jaws to the sealant layers of the packaging material.

Force

Increasing the force that closes the sealing jaws improves Thermal Transfer Efficiency by increasing the surface contact between jaws and the packaging material.

But the ability to increase force is limited on most vertical baggers and long-dwell wrappers.

XR™* Sealing Jaws

1. Improve Package Quality

Utilizing unique serration geometry and Dura-Therm material, Greener Corporation’s XR™* Sealing Jaws distribute a machine’s existing sealing force more effectively to increase Thermal Transfer Efficiency and improve package quality.

2. Increase Machine Speed

The improved Thermal Transfer Efficiency yields wider seal ranges at shorter dwell times to allow increased machine speeds.

3. Run Sustainable Materials & Hard to Seal Packages

XR™* Sealing Jaws increase seal quality and machine speed where the need for longer dwell times has previously created limitations, such as with thicker and stiffer materials, wider packages, gusseted applications, mono PE and other materials with narrow seal ranges, and poorly conducting materials like paper.

4. Reduce Flexible Packaging Costs

By increasing Thermal Transfer Efficiency, XR™* Sealing Jaws enable users to decrease sealant thickness or utilize less expensive sealants with higher seal initiation temperatures to reduce flexible packaging material costs without sacrificing seal quality or productivity.

To learn how XR™* Sealing Jaws can:

Improve Package Seal Quality
Increase Machine Speeds
Run Sustainable Materials and Hard to Seal Packages
Reduce Material Costs

on your vertical baggers and long dwell flow wrappers, contact Greener Corporation. We provide integrated parts and technical services worldwide.

* patent pending

The post XR™* Sealing Jaws Improve Thermal Transfer Efficiency to Provide Better Seals, Faster appeared first on Greener Corporation.

Preventative Maintenance Quick Tips for Flow Wrappers and Vertical FFS Baggers

Michael Wojtech — Sun, 27 Oct 2024 12:20:59 +0000

Many simple, easily implemented setup and preventative maintenance steps on flow wrappers and vertical baggers can have an outsized effect on package quality and productivity.

This Greener Tech Bite presents a series of Quick Tips that prevent cutting, sealing, and forming problems and help you troubleshoot issues when they do occur.

Cutting

Clean Knife and Anvil Slots

The value of cleaning on a regular schedule, instead of waiting until product contamination causes problems, can’t be overstated.

To clean knife and anvil slots on rotary sealing jaws, cut a piece of scouring pad and push it down into the slot with a hex wrench. And don’t neglect to clean the anvil slot, even though it can be more challenging to access.

Product buildup in the slot creates an unstable base that can cause intermittent cutting problems and knife failure.

Sealing

Clean Sealing Jaws Regularly

Clean sealing jaws regularly, but don’t use stiff, coarse bristled brushes—they damage the serrations and cause sealing problems.

Brushes with finer, softer bristles are more forgiving. They can be trimmed in length to clean more effectively and to keep them from splaying out.

After cleaning the jaws, run a carbon impression to check the current set up so that you can make any necessary corrective adjustments before resuming production.

Install Sealing Jaws with New Bolts and Washers

Install sealing jaws with new mounting bolts and washers. Worn, damaged bolts and washers, which can easily go unnoticed, cause inaccurate mounting and make jaws difficult to remove in the future.

To ensure accurate setup and to prevent the jaws from shifting out of alignment, use hardened, flat washers to mount jaws on flat surfaces.

Spherical washers or, if they are not available, split washers are best for mounting jaws on round shafts.

Replace All Rotary Sealing Jaws at the Same Time

Replace all rotary sealing jaws on a machine at the same time, and make sure all the jaws come from the same supplier.

You may be tempted to replace only one jaw, or just one of multiple pairs, to save time or reduce costs. But inaccurate setup caused by sealing jaws with different wear levels and designs creates sealing problems.

Check Sealing Jaw Temperatures with a Pyrometer

Sealing jaws are often hotter in the middle than at the ends, where heat dissipates more quickly. The controller, however, does not reveal this variability, since it usually only indicates the temperature at one point within the jaw.

Use a pyrometer to regularly check multiple points across the functional length of the sealing face, to make sure temperatures remain within the seal range for your flexible packaging material and conditions.

Ongoing issues with inconsistent sealing temperatures can be solved with updated heater and sealing jaw designs.

Forming

Vertical Baggers: Maintain Proper Roller Adjustment

On vertical baggers, adjust the rollers to create even, consistent contact between the material and the forming collar wing—between positions 1 and 2 in the diagram.

Too much, too little, or uneven tension, demonstrated by positions 3 and 4, can cause wrinkles and creases that degrade package appearance and cause sealing problems.

Flow Wrappers: Adjust & Tighten Guide Rails & Deck Plates

On flow wrappers, make sure the product guide rails and deck plates are adjusted and tightened properly, and exercise care when removing and reinstalling deck plates—they can be easily bent or otherwise damaged.

Misadjusted rails or deck plates that are not level and smooth can inhibit the movement of the product and packaging material and cause malformed packages that delay production.

Also make sure the forming box is square and level.

Preventative Maintenance Quick Tips

By investing a relatively small amount of consistent time and effort, preventative maintenance can help you decrease problems that delay production and reduce package quality.

To learn more about solutions for improving package quality and productivity on flow wrappers and vertical baggers, visit our Technical Resource Blog and contact Greener Corporation.

We provide integrated parts and technical services worldwide.

The post Preventative Maintenance Quick Tips for Flow Wrappers and Vertical FFS Baggers appeared first on Greener Corporation.

Review of Seven Seal Testing Methods for Flexible Packaging

Michael Wojtech — Tue, 28 May 2024 17:59:22 +0000

Before you can determine the best seal testing method for your flexible packaging application, you need to clearly identify your requirements for seal strength and hermiticity. Then you can use these criteria to evaluate different methods and to accurately interpret test results.

This Greener Tech Bite explains the objectives, methods, results, and limitations of seven common seal tests for packages produced by flow wrappers and vertical baggers. We begin with seal strength tests, followed by tests for hermeticity, and conclude with a summary chart for easy comparison.

1. Peel Strength Test

Objectives: Peel Strength Tests measure seal strength, the ability of a package to remain sealed when subject to tension.

Methods: Seals are produced on a lab sealer at a series of different temperatures, with pressure and dwell time remaining constant. A testing device measures the force required to peal each seal apart.

Results: The force required to peel a unit width of seal is correlated with sealing temperature to compare the seal strength of one packaging material against another, or against historical data.

Limitations: Set points for temperature, pressure, and dwell time are typically standardized to ensure repeatability and inter-lab correlatability. They don’t necessarily represent production settings and therefore don’t indicate real-world results.

Sometimes seals are tested by pulling them apart by hand. This method does not produce repeatable Peel Strength results, though a seal that fully delaminates across the package width indicates seal strength that exceeds the material’s tear resistance.

2. Hot Tack Test

Objectives: Hot Tack Tests measure the strength of a seal while still warm.

Methods, Results, & Limitations: Test methods, results, and limitations are very similar to peel strength tests, except force is applied instantaneously, before the seal can cool.

3. Burst Resistance Test

Objectives: Burst Resistance Tests measure the pressure required to burst a package.

Methods: An unrestrained package is inflated until the internal pressure causes seal failure.

Results: Burst pressure values are often used to evaluate the effects of elevational pressure changes when packages are shipped.

Limitations: Since outcomes depend on package size and geometry—a given pressure level generates greater force across a wider package—Burst Resistance Tests don’t provide easily comparable values for seal strength.

4. Water Vacuum (Bubble) Test

Objectives: The Water Vacuum Test identifies the presence and location of leaks and is also used to assess leaks caused by pressure changes during shipping.

Methods: Packages are held under water in a sealed tank, where a vacuum is drawn. Bubbles appear when air inside the package is forced through leaks from higher to lower pressure.

Packages may also be squeezed under water by hand to look for bubbles.

Results: The presence of bubbles provides visible evidence of leaks and their location.

Limitations: Water Vacuum Tests don’t accurately measure leak size, since results are influenced by the initial air fill, size, and geometry of the package. Initial air fill must also be considered when assessing the impact of pressure changes during shipment.

Since the manual squeeze test is not accurately repeatable, results can be inconsistent.

5. Dye Leak Test

Objectives: Dye leak tests can also indicate the presence and location of leaks.

Methods: Colored dye is injected into the package, which is held for a set time with the seal oriented horizontally at the bottom and then inspected.

Results: Leaks are indicated by places where the dye has migrated through the seal.

Limitations: The Dye Leak Test tends to be less sensitive for smaller leaks and doesn’t quantify the magnitude of leaks.

6. Pressure Decay Test

Objectives: Pressure Decay tests measure both the presence and the magnitude of leaks.

Methods: A package is inserted into chamber, where a vacuum is drawn that pressurizes the package. If leaks are present, air is forced from the package into the chamber and the vacuum pressure decays.

Older pressure decay methods don’t use a chamber or create a vacuum, but instead inject air to achieve pressurization.

Results: Reductions in pressure indicate leaks; the rate of reduction reflects the size and overall magnitude of the leaks.

Limitations: With older Pressure Decay testing devices, the pressurized package will expand in volume. Excessive pressurization may result in seal creep or stretching and skew results. This limits the maximum seal test pressure, especially as package size increases.

The newest devices resolve these issues by restraining the package in a flexible bladder that prevents the pressurized package from expanding, allowing much higher pressures to be used.

Since the natural pressure decay rate decreases as pressure decreases, as illustrated on this graph, results from this test method are more precise for smaller leaks and lose accuracy as leak sizes increase.

7. Gas Flow Detection Test

Objectives: Gas Flow Detection Tests also measure the presence and magnitude of leaks.

Methods: A package is inflated or evacuated with a needle probe; the device monitors the gas flow required to maintain a set pressure level.

Results: Any gas flow required to maintain a given pressure indicates the presence and magnitude of leaks.

Limitations: Since pressure levels produced by Gas Flow Detection devices are limited, accuracy is best for medium to larger sized leaks.

Summary Chart: Seven Seal Testing Methods for Flexible Packaging

This summary chart will help you compare all seven seal tests for flexible packaging on your flow wrappers and vertical FFS baggers.

If you’d like help defining your sealing objectives and evaluating seal testing methods, contact Greener Corporation. We provide package quality and productivity solutions worldwide.

The post Review of Seven Seal Testing Methods for Flexible Packaging appeared first on Greener Corporation.

Sealing Leaks at the Triangle of Death on Flow Wrappers and Vertical Baggers

Michael Wojtech — Fri, 12 Apr 2024 15:06:28 +0000

Are you consistently meeting your standards for package seal integrity and production speeds on your flow wrappers and vertical baggers? This Greener Tech Bite explains causes and solutions for a common package sealing problem where high integrity seals are required—the unsealed gap where the lap seal or fin seal intersects the end seal, sometimes referred to as the “Triangle of Death.”

For anyone who has struggled to seal these gaps, this nickname is no exaggeration.

Package Geometry

On a typical package, the end seal thickens from two to three layers where the vertical sealing overlaps, or from two to four layers where the fin seal folds over. On packages with gussets this transition occurs multiple times, creating, in effect, a series of plateaus and abrupt valleys.

Packaging Material Structure

To consistently seal the gaps created at these transition points, the structure of your flexible packaging material must be appropriate for your package geometry, required machine speeds, and other conditions.

The Sealing Process

But limitations within the seal packaging process can cause leaks at the Triangle of Death to persist.

Temperature Cycles

As explained in our previous Tech Bite, sealing jaw temperatures fluctuate as each package is sealed, and temperatures vary more widely if production slows down or is interrupted.

Seal Range

Machine speeds are limited by the need to keep these temperature cycles within the seal range of your packaging material.

Heat, Pressure, and Time

With adequate heat, pressure, and dwell time, sealant layers designed with the necessary mass and flow properties—shown here in yellow—can flow into and seal off the Triangle of Death.

But sealing jaw temperatures must remain below the point where they distort or melt the exterior packaging material layers, shown here in blue.

Sealing pressure helps to move sealant into these gaps, but too much pressure can crush or split the seal, especially at thicker sections where the lap seal, fin seal, or gussets intersect

It can be difficult to sustain the balance of heat and pressure required to seal these gaps while also maintaining required machine speeds.

Sealing Jaw Design and Setup

Here’s where improving the design and setup of your sealing jaws can help you seal the Triangle of Death.

Dura-Therm

Jaws made from Dura-Therm, a highly conductive alloy, reduce temperature cycles so you can maintain seal quality at higher speeds.

Serration Pattern

Sealing jaw serration patterns are not universal; your sealing jaw serrations should be designed to optimize sealing pressure and heat transfer for your specific packaging conditions.

XR™* Sealing Jaws

Greener’s XR™* Sealing Jaws combine the benefits of Dura-Therm and our unique serration geometry to seal leaks at the Triangle of Death and:

Improve Package Quality
Increase Machine Speed
Run Sustainable Materials & Hard to Seal Packages
Reduce Flexible Packaging Costs

Easy Seal™ FLEX

Easy Seal™ FLEX Jaws accommodate the extra thickness at the fin seal fold to further optimize sealing pressure and heat.

Setup Procedures and Training

Once you determine the optimal sealing jaw design for your application, establish proper sealing jaw setup procedures and provide training to consistently produce high-quality seal packaging.

If you experience sealing problems at the Triangle of Death, consult with our experts at Greener corp about packaging material specifications, sealing jaw designs, and setup procedures for your flow wrappers and vertical baggers.

Greener Corporation provides integrated parts and technical service solutions worldwide.

* patent pending

The post Sealing Leaks at the Triangle of Death on Flow Wrappers and Vertical Baggers appeared first on Greener Corporation.

Sustainable Packaging Materials 2: Running Mono Polyethylene & Mono Polypropylene on Flow Wrappers & Vertical FFS Baggers

Michael Wojtech — Thu, 08 Feb 2024 14:51:49 +0000

Most traditional flexible packaging is made from multiple layers of different materials that can’t be easily separated. Mono polyethylene (PE) and mono polypropylene (PP) are produced from the same or similar materials, and are the most common polymer-based sustainable packaging materials we’ve encountered so far.

Segment 2 in our Sustainability Series explores the properties that can make mono PE and mono PP more challenging to form, cut, and seal, and presents solutions for maintaining package quality and machine speeds when running these materials on flow wrappers and vertical FFS baggers.

FORMING Mono PE & Mono PP Packaging Materials

During the forming process, the thicker, stiffer nature of mono PE and mono PP structures creates greater tension in the web. On both flow wrappers and vertical baggers, a power film drive will help keep these structures tracking properly.

Specially designed formers are often required to maintain consistently sized packages that are free from creasing and scoring.

CUTTING Mono PE & Mono PP Packaging Materials

The mechanical properties of these thicker and stiffer structures can also make cutting more challenging.

Knives designed for your specific packaging material will improve cutting performance.

Special features such as an extreme angle zig zag knife can improve openability for the consumer.

SEALING Mono PE & Mono PP Packaging Materials

As explained in our previous Tech Bite, the effective seal range of a packaging material is defined as the difference between the seal initiation temperature and the distortion temperature.

With all flexible packaging materials, machine speeds are limited by the need to fit normal sealing jaw temperature cycles within the seal range.

Many current mono PE and mono PP structures have a lower distortion temperature, which decreases their seal range.

And since these mono structures tend to be thicker and stiffer, higher sealing jaw temperatures are needed for heat to reach and activate the sealant layer. This further reduces the seal range.

With sealing jaw temperature increases limited by the lower distortion point, reductions to machine speed may be necessary to provide adequate dwell time for seal initiation.

Sealing Solutions

Advanced sealing jaw designs can help mitigate sealing issues encountered with mono PE and mono PP materials. Sealing jaws made from Greener Corp’s proprietary Dura-Therm alloy provide more responsive and consistent thermal conductivity across the sealing face to reduce temperature cycle fluctuations and help maintain seal quality and machine speeds.

Temperatures don’t spike as high when the machine idles, or drop as far when the line restarts.

Customized sealing jaw serration patterns and options such as Easy Seal™ FLEX jaws can also reduce temperature cycles by optimizing thermal transfer and sealing pressure.

In addition to sealing jaw design, optimized adjustment procedures and training are critically important for maintaining seal quality and machine speeds on flow wrappers and vertical baggers.

To learn more about sustainable flexible packaging materials, advanced part designs, machine adjustments, and training, contact Greener Corporation.

We provide integrated parts, industrial packaging solutions and technical services worldwide.

The post Sustainable Packaging Materials 2: Running Mono Polyethylene & Mono Polypropylene on Flow Wrappers & Vertical FFS Baggers appeared first on Greener Corporation.

Packaging Material Seal Range & Temperature Cycles on Flow Wrappers & Vertical FFS Baggers

Michael Wojtech — Tue, 09 Jan 2024 19:30:36 +0000

Packaging material seal range and sealing temperature cycles can limit seal quality and reduce machine speeds on flow wrappers and vertical baggers.

This Greener Tech Bite explains the factors that determine seal ranges and presents solutions for maintaining temperature cycles within this range to optimize package quality and productivity.

Packaging Material Seal Range

During the sealing process, temperatures are highest where the sealing jaws contact the package and then dissipate as heat travels through the core layers to the sealant. This heat transfer becomes a race against time. The goal is to reach seal initiation temperature at the sealant layer as quickly as possible without heating the core layers to their distortion temperature.

A material’s seal range is defined as the difference between the seal initiation temperature and the distortion temperature.

Sealing Jaw Temperature Cycles

Steady Production

A wide seal range allows for normal variability within the packaging process. A main source of this variability is the normal temperature cycle of the sealing jaws.

During steady production, temperatures dip as the sealing jaws transfer heat to the packaging material and then recover when the heat cartridges are energized. These fluctuations generally cycle within a few degrees on most machines.

Interrupted Production

But when production is interrupted, the sealing jaws are no longer transferring heat to the packaging material and jaw temperatures spike.

When production resumes, temperatures drop significantly and then, after a few moments, recover and return to normal.

Seal Range and Temperature Cycles

An appropriate seal range must allow for sealing jaw temperature cycles that include the impact of production interruptions.

When materials with a narrower seal range are run, or when temperatures cycle above or below the seal range, poorly sealed and distorted packages are produced.

Seal Range and Machine Speed

The effective seal range narrows as machine speed increases and seal dwell time is reduced. When heat reaching the sealant layer fails to attain seal initiation temperature, compensating temperature increases are limited by the distortion temperature of the core material layers.

Seal Range, Machine Speed, and Temperature Cycles

Maximum production speeds are limited by the seal range of the packaging material, which must accommodate the temperature cycle of the sealing jaws.

For high-speed applications, film suppliers can provide materials with lower seal initiation temperatures that increase machine speed potentials. But these materials are often more costly.

Dura-Therm Sealing Jaws

Sealing jaws made from Dura-Therm, a durable alloy with excellent thermal conductivity, have been shown to decrease temperature cycle fluctuations by 80% or more.

Dura-Therm sealing jaws provide excellent seal quality at higher speeds and for packaging materials with narrower seal ranges, such as today’s sustainable mono materials.

Specially designed sealing jaw serration patterns can further reduce temperature cycles by optimizing sealing pressure and heat transfer.

To learn how we can help you optimize seal quality and machine speeds, and to run packaging materials with narrower seal ranges, contact Greener Corporation. We provide integrated parts and technical services worldwide.

The post Packaging Material Seal Range & Temperature Cycles on Flow Wrappers & Vertical FFS Baggers appeared first on Greener Corporation.

Improving Hot Tack & Seal Quality on Vertical Baggers

Michael Wojtech — Mon, 14 Aug 2023 19:36:12 +0000

What’s the ultimate combination of heat, dwell time, and pressure for producing quality seals on vertical baggers? The answer varies, depending on your machinery, packaging materials, and conditions. But in all cases Hot Tack is an important, but often overlooked, consideration.

This Greener Corporation Tech Bite explains Hot Tack and its role in the heat + time + pressure sealing equation for packaging machines with reciprocating, non-rotary sealing jaws.

Hot Tack

Hot Tack refers to the strength of a seal while it’s still warm.

All packaging materials have an Effective Sealing Temperature Range between the Melt Point, or Seal Initiation Temperature (SIT) of the sealant layer, and the Distortion Point, where package appearance and seal quality deteriorate.

Modern sealants have been engineered to provide excellent seal strength. But packages have little or no strength until seals have cooled below the melting point of the sealant layer.

Sealing Problems

During the bag making or case packing process, poor hot tack presents as mooning or complete failure of a seal that has been stressed while it’s still too warm.

Hot Tack problems are often caused by sealing temperatures that are set too high. These issues are especially prevalent with thicker, stiffer packaging materials, which can be more difficult to transfer heat through and often prompt a temperature increase.

Improving Hot Tack

Reduce Temperature

The best method for improving Hot Tack is to reduce temperature settings, so that the sealant layer cools below its melt point more quickly. Left as an isolated adjustment, however, reduced heat could cause poor seal integrity on the initial package seals.

Increase Time + Pressure

But since heat, time, and pressure are closely linked and can be interdependent, a compensating increase in dwell time, pressure, or both can maintain seal quality.

Longer dwell times are often not feasible, since they slow down production and reduce output.

But machine adjustments and customized sealing jaw designs can provide greater pressure and better surface contact between the packaging material and the sealing jaw serrations. More heat is driven through to the sealant layer within a given time period, and temperatures can be reduced.

Package Width & Seal Width

It’s important to recognize that package dimensions affect sealing pressure levels.

As a package becomes wider, seal jaw force is diluted over a greater area, and the effective pressure transferred to the seal at any given point is reduced. Wider packages generally require longer dwell times than smaller packages.

Narrower seal widths also supply greater pressure at any given point by concentrating it into a smaller area.

Reducing seal width may require a corresponding decrease in sealing temperature that improves Hot Tack and can reduce per-package film costs.

Refining your machine adjustments and sealing jaw designs will help you provide the extra pressure needed to optimize Hot Tack, and at the same time improve seal quality and productivity.

To receive recommendations for optimizing Hot Tack on your packaging application, contact Greener Corporation. Greener Corporation provides Integrated Parts and Technical Services worldwide.

The post Improving Hot Tack & Seal Quality on Vertical Baggers appeared first on Greener Corporation.

Sealing Temperature Archives - Greener Corporation

How to Determine the Optimum Machine Speed on Flow Wrappers and Vertical FFS Baggers

Sealing Jaw Temperature Cycles

Setup for Maximum Machine Speed

Steady Production Rate

Variable Production Rate

Maximum vs. Slower, Steady Machine Speed

Flow Wrapper

A. Setup for Maximum Machine Speed

B. Setup for Slower, Steady Machine Speed

A: Maximum vs. B: Slower, Steady Machine Speed

Vertical Bagger

A: Maximum vs. B: Slower, Steady Machine Speed

Slow is Smooth, and Smooth is Fast

Dura-Therm and XR™* Sealing Jaws

Increase Output

Convert to Sustainable and Less Expensive Packaging Materials

Slower and Steady Wins the Race

How the Structure of Flexible Packaging Materials Impacts Their Sealability

Flexible Packaging Materials

Polymer Type & Thickness

Laboratory Melt Point Spread

Seal Range

Laboratory Melt Point Spread vs Seal Range

Thermal Transfer Efficiency (TTE)

Seal Range Factors

Dwell Time – Machine Speed

Flexible Packaging Material Thickness

Temperature

Flexible Packaging Material Structure

Increase Thermal Transfer Efficiency (TTE) to Expand Seal Range

XR™* Sealing Jaws

Sustainable Materials & Difficult to Seal Packages

Reduce Flexible Packaging Material Costs

Optimizing Fin Wheel Performance on Flow Wrappers

Inspect

Check Bearings

Test Sealing Pressure

Check Adjustments and Design

1. Inspect

Damage, Wear, Sharp Edges

Clean

2. Check Bearings

3. Check Sealing Pressure

4. Check Adjustments and Design

Temperature

Tilt

Gripper Grooves

Dura-Therm

Product Presentation & Package Formation

XR™* Sealing Jaws Improve Thermal Transfer Efficiency to Provide Better Seals, Faster

The Sealing Process

Seal Range and Temperature Cycles

Machine Speed

Thermal Transfer Efficiency

Force

XR™* Sealing Jaws

1. Improve Package Quality

2. Increase Machine Speed

3. Run Sustainable Materials & Hard to Seal Packages

4. Reduce Flexible Packaging Costs

Preventative Maintenance Quick Tips for Flow Wrappers and Vertical FFS Baggers

Cutting

Clean Knife and Anvil Slots

Sealing

Clean Sealing Jaws Regularly

Install Sealing Jaws with New Bolts and Washers

Replace All Rotary Sealing Jaws at the Same Time

Check Sealing Jaw Temperatures with a Pyrometer

Forming

Vertical Baggers: Maintain Proper Roller Adjustment

Flow Wrappers: Adjust & Tighten Guide Rails & Deck Plates

Preventative Maintenance Quick Tips

Review of Seven Seal Testing Methods for Flexible Packaging

1. Peel Strength Test

2. Hot Tack Test

3. Burst Resistance Test

4. Water Vacuum (Bubble) Test

5. Dye Leak Test

6. Pressure Decay Test

**A: Maximum vs. B: Slower, Steady Machine Speed**

**A: Maximum vs. B: Slower, Steady Machine Speed**