Carbon Impressions Archives - Greener Corporation

Maintain Efficiency on Flow Wrappers with Systematic Preventative Maintenance

Michael Wojtech — Tue, 11 Nov 2025 16:46:06 +0000

A Tech Bite from Greener Technical Service Manger Jeff Fouche

Due to production demands and a shortage of experienced mechanics, maintenance on flow wrappers is often reduced to immediate problem solving. In the rush to restore production, this reactive maintenance relies on short-term fixes that don’t fully resolve the underlying cause of the problem and fail to restore peak efficiency. Repeat problems require additional quick fixes and further erode efficiency.

This Greener Tech Bite details systematic preventative maintenance practices for flow wrappers that sustain peak efficiency and production levels.

If you and your team don’t have the required time or experience to implement preventative maintenance, Greener’s Technical Specialists can provide regularly scheduled onsite visits to perform line evaluations, make necessary updates, and provide training on these procedures.

Systematic Preventative Maintenance

The following flow wrapper components and adjustments—from the product feed through to the package discharge—should be evaluated and updated at least every three months.

Product Infeed

On the product infeed, stretched or worn components cause product misalignment and create timing problems. Replace worn or stretched infeed flight chains. Inspect the belts—even those with automatic tensioners—and replace them if they are stretched, worn, or frayed and can’t hold the proper tension.

The product infeed should be level and aligned with the flow wrapper.

Rails – Deck Plates – Forming Box

Check the rails, deck plates, and the forming box for misalignment or damage and readjust, repair, or replace them as needed.

When not level, smooth, or properly positioned, these components inhibit movement of the product and packaging material, causing malformed packages that delay production.

Packaging Material Unwind

Replace the bearings of shafts and rollers on the packaging material unwind that don’t spin freely; they create excess tension that causes tracking problems.

Adjust rollers to create the proper tension on the packaging material as it moves throught he forming process.

Fin Wheels

Fin wheel issues can cause slippage, poor tracking, and seal problems. Make sure that the tension between the fin wheels is correct and adjust their tilt to prevent slippage and create tighter packages.

Replace fin wheels that are worn, damaged, or have sharp edges. Check the condition of the fin wheel bearings and replace them if needed.

Cutting and Sealing Head

The cutting and sealing head requires frequent inspection and updating.

Backlash

Check for and remove backlash between the upper and lower sealing jaws.

Gears

Inspect the gears and replace them if necessary.

Springs or Compression Washers

Assess the condition of the springs or compression washers and adjust or replace them as needed.

Bearings

Worn bearings cause chronic problems that can be difficult to diagnose. To determine if new bearings are needed, follow this bearing evaluation process.

Carbon Impression

Next, remove the knives and anvils and, with the sealing jaws at operating temperature, run carbon impressions to evaluate their condition and setup.

Sealing Jaws and Adjustments

Replace worn or damaged sealing jaws. Check and, if needed, readjust the clearance, phasing, serration alignment, and pressure.

Clean the slots to ensure that knives and anvils can be firmly and accurately seated. To prevent cutting problems, always replace the anvil when installing a new knife.

After adjusting the knife with shims or adjustment screws, re-check your sealing setup with another carbon impression.

Cleaning

At any point in the packaging process, insufficient cleaning can degrade efficiency.

Clean components such as belts, formers, deck plates, fin wheels, and both the upper and lower sealing jaws during scheduled production breaks and whenever time allows—before problems occur.

Regularly Scheduled Preventative Maintenance with Greener Corporation

Relying on reactive maintenance erodes package quality and output levels.

If you don’t have a systematic preventative maintenance program for your flow wrappers, consider partnering with Greener Corporation for regularly scheduled Technical Service visits. Our Technical Specialists will perform line evaluations, make necessary updates, and provide training to keep your flow wrappers running at peak efficiency.

To learn more contact Greener Corporation. We provide integrated parts and technical service solutions worldwide.

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Use Sealing Jaw Carbon Impressions for Preventative Maintenance

Michael Wojtech — Tue, 29 Apr 2025 07:47:34 +0000

A Tech Bite from Greener Technical Service Specialist Chris Stawasz

Sealing jaw carbon impressions are a vital diagnostic tool for solving cutting and sealing problems on flow wrappers and vertical baggers, and they also play a vital role in preventative maintenance.

This Greener Tech Bite outlines five opportunities where sealing jaw carbon impressions help you prevent problems from occurring in the first place.

Take Sealing Jaw Carbon Impressions

Whether solving problems or preventing them, always label your impression with the date, line and machine, direction arrow, and sealing jaw pair number so you can compare results over time and track changes.

We use “carbon impression” as a general term, but in practice make sure you use the correct paper for your application.

Carbon paper works best with unheated rotary sealing jaws and with reciprocating jaws at lower temperatures.

Use carbonless paper, also known as NCR paper, with heated rotary jaws and with reciprocating jaws at higher temperatures.

1. When You Install New Sealing Jaws

When you install new sealing jaws, bring them to operating temperature and use carbon impressions to evaluate your setup.

Clearance

For rotary jaws, use carbon impressions to ensure that the clearance between the upper and lower shafts is properly set and parallel.

Phasing

A carbon impression will also indicate if the phasing between the shafts is synchronized.

Alignment

For both rotary and reciprocating jaws, carbon impressions indicate if the serrations are misaligned.

Pressure

And carbon impressions will help you adjust sealing pressure so that it is even from side to side and across the length of the jaws.

2. Before You Install New Knives and Anvils

When knives and anvils on flow wrappers need to be replaced, remove the worn parts, make sure jaw temperatures are set correctly, and take a carbon impression before you install new knives and anvils. This quick, easy test will indicate if readjustments are needed to restore your standard setup and prevent future problems.

3. After You Clean the Sealing Jaws

A pause in production for cleaning provides another opportunity. After you clean the jaws, check your temperature settings and run a carbon impression to determine if spring pressure, alignment, or other settings have changed and need to be readjusted.

4. When You Run New Flexible Packaging Materials

Carbon impressions also provide vital feedback when you test and run new flexible packaging materials. Before you run a new material, bring your sealing jaws to operating temperature and run a carbon impression to ensure that your adjustments are at standard levels.

Take additional impressions as you test the new material; your new structure may have a different heat seal range, thickness, stiffness, or other characteristics that require refinements to your sealing jaw and knife setup.

5. Every Week and During Downtime

Systematic carbon impressions provide the feedback you need to prevent packaging problems. Schedule weekly carbon impressions from each flow wrapper and vertical bagger, and take additional impressions when opportunities arise during product changeovers and other downtime.

If you’d like help diagnosing your carbon impressions, send us a photo at custserv@greenercorp.com. We’ll help you identify adjustments that improve packaging performance.

Greener Corporation provides integrated parts and technical service solutions worldwide.

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Intermittent Cutting & Sealing Problems on Flow Wrappers: Diagnosing Worn Bearings

Michael Wojtech — Mon, 24 Feb 2025 05:07:25 +0000

A Tech Bite from Greener Technical Service Specialist Jeff Fouche

It can be difficult to determine the cause of intermittent cutting and sealing problems on flow wrappers. Issues may occur on two or three packages and then resolve, only to continually repeat at random intervals—perhaps in five minutes, then after twenty packages, and again an hour later.

This Greener Tech Bite explains how to diagnose and fix intermittent cutting and sealing problems on flow wrappers caused by worn bearings and other factors.

Severely Worn Bearings

Severe bearing wear causes cutting and sealing problems that are consistent, not intermittent. This severe wear allows movement in the shafts that you can feel when you tightly grip and push them up and down or side to side.

Uneven, Less Severe Bearing Wear

When bearings wear unevenly and develop random flat spots, you won’t be able to feel the shafts wiggle. Determining if this less severe bearing wear is creating your intermittent cutting and sealing problems requires the process of elimination—you will first need to rule out three other possible causes:

Worn Gears
Backlash
Misaligned Sealing Jaws
Worn Bearings

1. Worn Gears

To start, visually inspect the gears and replace them if they are worn. Worn gears mesh inconsistently and can cause poor seal quality and incomplete cuts at random intervals, especially when the wear is uneven.

Learn more from our post and video on the effects of worn gears.

2. Backlash

Also inspect for and remove backlash, or independent rotational movement between the upper and lower sealing jaws. Backlash causes intermittent cutting and sealing problems by allowing the knife to swipe across or leave multiple impressions on the anvil and by misaligning the serrations.

Visit our post and video about diagnosing and adjusting backlash on flow wrappers for more details.

3. Misaligned Sealing Jaws

Once backlash has been removed, the sealing jaws may still be misaligned. Run a carbon impression and check the alignment of the serrations. Misaligned jaws wear unevenly and cause intermittent problems when they don’t mesh properly.

Consult our Tech Bite on diagnosing sealing jaw misalignment with carbon impressions for more information.

4. Worn Bearings

If intermittent problems persist after you check and correct the first three issues, then your bearing are worn and should be replaced.

There is no reliable way to determine which bearings are bad, so when you invest the time to access the bearings you should replace all four of them.

The new bearings should eliminate your intermittent cutting and sealing problems.

If you would like to improve the forming, cutting, and sealing performance on your flow wrappers and vertical baggers, connect with Greener Corporation’s technical experts.

We provide integrated parts and technical service solutions worldwide.

The post Intermittent Cutting & Sealing Problems on Flow Wrappers: Diagnosing Worn Bearings appeared first on Greener Corporation.

Setting Up Sealing Jaws on Horizontal Flow Wrappers

Michael Wojtech — Sat, 30 Mar 2024 19:12:24 +0000

Proper sealing jaw setup is critical for producing consistent quality packages; even slight misadjustments can damage the package and cause leaks that prevent you from meeting quality packaging standards.

This Greener Tech Bite explains nine essential procedures for accurately setting up sealing jaws on horizontal flow wrappers.

1. Clean the Shafts

Begin by removing the old sealing jaws and cleaning the shafts of any product buildup.

2. Sealing Jaws

Replace all sealing jaws on a wrapper at the same time, and make sure all the jaws come from the same packaging machinery supplier.

You may be tempted to replace only one seal jaw, or just one of multiple pairs, to save time or reduce costs. But running sealing jaws with different wear levels or different designs causes inaccurate setups that create sealing problems.

3. Insert Heaters and Thermocouples

For heat seal applications, coat heaters and thermocouples with heat sink compound before inserting them in the jaws. This will fill in air gaps to improve heat transfer and sensing accuracy.

4. Install Sealing Jaws on Shafts

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

To help ensure that the sealing jaws are accurately seated and don’t shift out of alignment, use hardened, flat washers on flat shafts and spherical washers or, if they are not available, split washers, on round shafts.

If possible, tighten bolts while the sealing jaws are meshed.

5. Heat the Sealing Jaws

For heat seal applications, bring the jaws to operating temperature before making adjustments.

6. Adjust Clearance

Begin by adjusting clearance, the narrow gap between the upper and lower sealing jaw serrations.

Many wrappers utilize clearance adjustment rods, as illustrated here. Some makes and models use wedges, shims, or other methods.

Rotate the sealing jaws together by hand to make sure they’re not hitting each other, and then run carbonless paper between them. Adjust clearance just wide enough to create an interference fit for the paper—about the same thickness as a double layer of your packaging material.

Check the carbon impression to make sure that the clearance is even from end to end and adjust accordingly.

7. Adjust Serration Alignment

Also use the impression to evaluate alignment and adjust the sealing jaws as needed so that the serrations mesh properly.

Our previous post on carbon impressions diagnoses examples of misadjusted clearance, alignment, and other issues.

8. Remove Backlash

Next check for backlash, or independent movement between the upper and lower sealing jaws.

With even minor backlash, the resulting misaligned serrations can damage and split the package and reduce seal quality.

On gear-driven wrappers a split gear on the non-drive shaft is used to remove backlash. Belt and chain-driven machines utilize a tensioner. Over time, worn gears and stretched belts and chains contribute to backlash, so periodically inspect these components and replace them when needed.

Learn more about backlash from these Tech Bite posts and videos.

9. Adjust Sealing Pressure

The next step is to adjust spring pressure. On most wrappers springs are adjusted and locked to create the pressure required to seal and cut packages. Some wrappers utilize compression washers.

Springs and compression washers often go unrecognized as the source of package sealing problems. Since evaluating their condition can be difficult, it is well worth replacing them on a regular basis.

Run five to ten packages through the sealing jaws, with product if available. Cut the packages with scissors and check seal integrity using your current testing method.

Adjust spring pressure as needed to meet your seal quality standards.

If you’re not producing quality seal jaws after following these procedures, discover the problem-solving solutions on our Technical Resource Blog and contact Greener Corporation for technical support. We provide integrated parts and technical services worldwide.

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Carbon Impressions Diagnose Misadjustments on Flow Wrappers

Michael Wojtech — Mon, 16 Oct 2023 18:30:22 +0000

Carbon impressions are a vital diagnostic tool for setting up sealing jaws on flow wrappers. This Greener Tech Bite reviews nine carbon impressions that illustrate some common flow wrapper adjustment errors.

With an accurate setup, your carbon impression will be uniform and consistent over the peaks and valleys of each serration, across the length of the sealing jaws, and on both seals.

1. Phasing Between Shafts Not Synchronized – Horizontal Serrations

On our first example, the impression is consistent from end to end and on both sides of the slot, but uneven over the peaks and valleys of each serration.

The dark, horizontal lines indicate that the serrations are hitting side to side and not meshing together evenly.

In this case we can rule out improper mounting of the sealing jaws as a cause of the misalignment, since on this wrapper the jaws fit into slots on the shaft that align them on the centerline.

Here the phasing, or timing, between the upper and lower shafts is not synchronized and needs to be readjusted so that the serrations are properly aligned.

2. Phasing Between Shafts Not Synchronized – Vertical Serrations

Our second carbon impression also indicates misadjusted phasing, but for sealing jaws with vertical serrations. The upper seal is weaker, a bit narrower, and has a row of sharp dots along the slot.

When phasing is out the knife and anvil slots may not line up. The dots were created when the crowns of the serrations on the upper jaw struck the anvil, which had been installed in the lower jaw.

The serrations here are also slightly misaligned—they hit harder on one side of each serration and leave a less uniform impression.

3. Severe Misalignment – Vertical Serrations

On this next example, severely misaligned vertical serrations only make narrow contact with each other and leave an impression of dark, well defined lines.

4. Clearance Not Parallel

Carbon impression four is lighter on the left end and darker on the right, indicating that the clearance between the shafts is not parallel and needs a slight adjustment.

Sealing Jaws Mounted on Flat Shafts

These next carbon impressions were made with sealing jaws that mount on a flat shaft surface, without a key, slot, or a radius that would align them with the centerline of the shaft.

5. Serrations Diagonally Misaligned

On this carbon, notice how the impression changes from one end to the other.

The dark, horizontal lines show that the serrations are not fully meshing and are hitting each other on opposite sides. From left to right on this view, the serrations hit harder on the bottom side, produce a faint impression in the middle, and hit harder on the upper side.

The sealing jaws are diagonally misaligned to each other and should be readjusted so that the serrations are parallel.

6. Serrations Diagonally Misaligned – Less Severe

This next example displays less severe diagonal misalignment; the impression is lighter on the upper left and lower right, and darker on the lower left and upper right.

7. Sealing Jaws Offset from Centerline of Shafts – Horizontal Serrations

Impression seven shows a readily noticeable misadjustment; the seal on one side of the slot is significantly narrower and weaker than the other side.

Here the knife and anvil slots and the serrations are aligned, but the pair of sealing jaws is offset from the center line of the shafts.

Since the radius of the sealing face doesn’t align with the radius that the jaws are rotating on, there is a gap between the serrations on one seal and the impression is narrower and weaker.

8. Sealing Jaws Offset from Centerline of Shafts – Vertical Serrations

When sealing jaws with vertical serrations are offset from the centerline, the seal widths on a carbon impression are often more consistent. But, as this example shows, the impression of one seal will still be weaker than the other.

9. Serrations Offset

On this last carbon impression the seal width on one side of the slot is also narrower and weaker—but here the cause is different.

In this case the sealing jaws are misaligned with each other by a full serration and the slots don’t line up.

The effective width of each sealing face is reduced and, since the working radii of the sealing jaws are offset, the seal on one side receives less pressure and is weaker and narrower.

Carbon impressions often indicate multiple setup issues and can be challenging to interpret. If you’d like help with diagnosing your impressions and developing solutions, contact Greener Corporation.

We provide integrated parts and technical services worldwide.

The post Carbon Impressions Diagnose Misadjustments on Flow Wrappers appeared first on Greener Corporation.

Diagnosing Packaging Problems – Part 1: Split, Fractured Seals

admin — Wed, 19 Oct 2022 00:14:32 +0000

When solving packaging problems, you’ll achieve the best results when you diagnose one symptom at a time and evaluate the effects of each corrective adjustment. This systematic approach will help you isolate the causes, determine the best solutions, and avoid steps that compound the problem and waste time.

In part 1 of this Greener Tech Bite we diagnose the most apparent problem on this package from a flow pack wrapper—the split in the upper left corner.

Split, Fractured Seals

Wrinkles & Creases

The leading edges of the sealing jaws are fracturing the film at the site of a wrinkle, which has likely caused or at least contributed to the problem. Extra wrinkles and creases can be reduced or eliminated by refining the product feed and package formation process. Use these links to consult posts and videos that explain these adjustments.

Let’s assume that our adjustments improved but did not eliminate the wrinkles. The splits still occur, but they are less severe. We need a carbon impression to determine our next steps.

Clearance

The carbon indicates more pressure on the end of the sealing jaws where the splits appear. This could indicate that clearance was not properly adjusted when the jaws were set up, or that clearance has since been changed.

As a general rule, clearance should be adjusted at initial set up and not altered. But to solve our problem we need to reset clearance and check it with a new carbon impression.

Alignment

The new impression displays more consistent sealing pressure; clearance has been correctly set. If the the splits persist, our next step is to fix the moderate serration misalignment shown on the carbon.

Backlash
Check for and remove backlash between the upper and lower sealing jaws. To learn more about adjusting backlash consult these posts and videos.

Sealing Jaw Design

If clearance and alignment adjustments don’t eliminate the split packages, an optimized sealing jaw design may be required to solve the problem.

Serration Pattern
The serration pattern should provide even, consistent sealing pressure for your specific film, package configuration, and running conditions.

Fracture Elimination Design (FRED)
You might need special design features such as Greener’s Fracture Elimination Design, which alleviates excess pressure at the leading edge of the sealing jaws that can fracture the package.

Diagnosing Packaging Problems – Part 2

Leakers & Inconsistent Pressure

Once you make the adjustments and jaw design changes necessary to eliminate splitting and fracturing, your package may still have problems with leaks and inconsistent sealing pressure. Packagers often need to maintain a narrow, difficult to achieve operating window that provides enough pressure to seal off leaks and avoids excess sealing pressure that splits or fractures the package.

We will diagnose potential causes and solutions for these problems in Part 2 of this Greener Tech Bite.

The post Diagnosing Packaging Problems – Part 1: Split, Fractured Seals appeared first on Greener Corporation.

Prevent Problems & Maintain Productivity with Carbon Impressions

admin — Tue, 04 Oct 2022 15:11:16 +0000

Carbon impression are most often used to guide the setup of sealing jaws and to solve problems on flow wrappers and vertical form fill seal baggers.

But Carbon impressions should also be taken before each new production run and when variables such as product size or packaging materials change. These extra impressions will indicate ongoing adjustments and preventative maintenance that prevent package quality problems and lost production time.

Adjustments & Preventative Maintenance

Carbon impressions indicate changes that occurred during previous production that might otherwise go unnoticed, such as damage to jaws and knives, product contamination, or misadjustment of the clearance, sealing pressure, and other variables. You might find that sealing pressure is uneven across the length of the jaws, or that the serrations are not properly aligned.

Damage

Product Contamination

Misadjustment

Alignment

Knife Adjustment

On flow wrappers, weak impressions from the trailing seal could indicate that a worn knife had been over adjusted to make it last through the previous production run. Here the knife is striking the anvil with such force that the jaws bounce apart and fail to transfer adequate sealing pressure. You will know to replace this knife and anvil before production resumes to avoid seal problems and delays.

When changes to the product, packaging material, line speed, or other conditions occur, take new carbon impressions. They will indicate if adjustments to alignment, temperature, sealing pressure, knife setup, or other variables are needed to maintain package quality.

Sealing Jaw Wear

For example, sealing jaws that have begun to wear may still be producing quality seals. But with a new, thinner packaging material this wear can prevent the jaws from providing adequate sealing pressure.

Label & Save

Be sure to label your carbon impressions with the date, line and machine, direction arrow, and sealing jaw pair number and to save them. Not everything these impressions reveal will require immediate action, but when urgent problems do occur you can compare current conditions with previous results, recognize what has changed, and resolve the issue.

Paper Type

For accurate results, use the right type of paper for your situation.

Use carbon paper for unheated rotary sealing jaws, at initial setup or for when running cold seal films. Carbonless paper should be used when the jaws are hot.

For cold or hot reciprocating sealing jaws use carbon paper. When these jaws are run at high temperatures, carbonless paper may improve results.

Invest a few extra minutes to make carbon impressions a standard part of your preventative maintenance program. You will keep packaging problems from occurring and save hours of lost production.

If you need a supply of carbon or carbonless paper, or would like help interpreting your impressions, contact Greener Corporation. We provide Package Quality and Productivity Solutions worldwide.

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Knife Adjustment on Flow Wrappers: The Cost of Quick Fixes

Mark Green — Mon, 30 May 2022 22:19:40 +0000

When cutting problems delay production, quick fixes are often used to get flow wrappers up and running again. But instead of saving a few minutes of downtime, these shortcuts can cost you hours of production time.

This Greener Tech Bite identifies common quick fixes that bypass standard knife adjustment procedures. Their immediate and cumulative effects cause well over half of the cutting and sealing problems that we encounter.

Clearance & Pressure

Clearance is the narrow gap or space between the upper and lower sealing jaw serrations. It should be adjusted when the jaws are set up—before knives and anvils are installed—and be just wide enough to create an interference fit for a double thickness of film.

Adjusting spring pressure doesn’t change this gap. Spring pressure provides the resistance and tension applied by the jaw serrations to create the seal and the force for the knife to cut against the anvil.

Clearance is frequently mistaken for spring pressure and adjusted as a shortcut to solve cutting problems. But this is not a good option. It’s not uncommon for an improper clearance adjustment to cause a cascade of cutting and sealing problems that cost multiple shifts of lost production.

We can’t overstate the importance of proper clearance adjustment: NEVER use clearance to adjust a knife.

Temperature

Another common shortcut when cutting issues arise is to increase the heat, which can expand the height of the knife and anvil enough to cut. These temperature changes may be fine in the short term, but they are meant to be temporary, to get through the shift.

The problem with this shortcut is that the temperature often does not get reset, and the root causes of the cutting issue are not addressed. The effects of these and subsequent quick fixes accumulate and cause additional cutting and sealing problems.

If the knife fails again, even with the extra heat, the mechanic might decrease clearance until the knife cuts. They may not realize, however, that the intermittent crushed and split seals that develop soon after are caused by the incorrect heat and clearance adjustments.

In this case the fastest and least expensive strategy would have been to readjust or replace the knife and anvil when the problem first appeared.

Knife Adjustments

Taking the time to follow these standard knife adjustment procedures, even during production, will produce the highest outputs and best package quality.

• Set up the sealing jaws first.

• Clean the jaws, including the slots, before installing knives and anvils.

• Change knives and anvils together.

• Use fewer, thicker, high-quality shims.

• Remember that temperature impacts knife adjustments.

• Optimize and standardize knife designs.

When to Adjust and When to Replace

If you follow standard procedures and a knife still won’t cut without excessive pressure or banging, stop making adjustments. The best solution is to replace the knife and anvil.

If you can’t adjust a new knife to cut without banging, don’t continue. There are likely other, underlying conditions that should be corrected such as worn springs or worn bearings.

Technical Support

If you’d like recommendations for improving your knife adjustments, send us samples or photos of used anvils and contact Greener Corporation. We develop and deliver full process solutions, worldwide.

The post Knife Adjustment on Flow Wrappers: The Cost of Quick Fixes appeared first on Greener Corporation.

Pressure & Heat: Adjustments & Sealing Jaw Designs

Matt Wojtech — Sat, 30 Apr 2022 18:48:14 +0000

This Greener Tech Bite reviews machine adjustments and sealing jaw designs that provide the pressure and heat* required for quality seals. You can consult additional, detailed posts and videos on each topic by clicking the red links or the corresponding images.

Quality seals on flow wrappers & vertical baggers require a combination of time, pressure, and heat, if utilized, that seals across varying thicknesses created by the fin or lap seal, gussets, or other pleats and wrinkles.

With time typically limited by high line speeds, your effective operating range for pressure and heat may be narrow and difficult to maintain. Too little leaves seals open or leaking; too much will split, distort, or damage the seal.

Adjustments

Product Feed & Package Formation

It’s important to consider your full packaging process. Adjustments to product feed and package formation can reduce variations in the size and location of the fin seal, lap seal, or gussets and eliminate extra wrinkles and folds that reduce seal quality.

(Click on the red links or images for detailed posts & videos on each topic.)

Flow Wrapper adjustments include product feed, film alignment and tension, and fin seal formation.

Vertical Bagger adjustments include product flow, roller position, and film drive. Former design and condition are also crucial.

Sealing

Carbon Impressions – Visual inspection of packages and leaker tests indicate problems with pressure or heat, but they don’t tell the full story. Carbon impressions reveal important but less obvious issues such as misaligned serrations, uneven pressure, jaw wear, and product contamination. Make carbon impressions part of your preventative maintenance program.

Knives and Anvils – On machines with rotary jaws, worn and incorrectly adjusted knives and anvils are often overlooked as a cause of leakers, damage, and other sealing problems.

Clearance and Pressure are critical adjustments on flow wrappers. But their differences, and when each should be adjusted, are not always clear.

Sealing Jaw Design

Sealing jaw designs are not universal; your jaws should be custom designed for your film, product, machinery, and running conditions.

(Click on the red links or images for detailed posts & videos on each topic.)

Serrations

The serration profile must transfer consistent pressure and heat across varying thicknesses of film.

Special Features

Special features may be required, such as:

Easy Seal™ FLEX sealing faces to seal across the fin seal.

Design Solutions

This case study demonstrates the benefits of properly designed sealing jaws.

Dura Therm material to ensure consistent sealing temperatures.

Standardization

Do your results vary across different shifts, makes and models of machinery, packaging lines, or locations? You can produce consistent quality seals by establishing standard adjustment procedures, providing training, and by standardizing former and sealing jaw designs.

(Click on the red links or images for detailed posts & videos on each topic.)

Standard Adjustment Procedures and Training

Standard Sealing Jaw Designs

If you need recommendations for machine adjustments and sealing jaw designs that optimize pressure, heat, and seal quality, contact Greener Corporation. We develop and deliver full process solutions, worldwide.

The post Pressure & Heat: Adjustments & Sealing Jaw Designs appeared first on Greener Corporation.

Sealing Jaw Carbon Impressions Reveal Multiple Problems

Mark Green — Mon, 18 Oct 2021 17:35:54 +0000

Sealing jaw carbon impressions provide a vital roadmap for diagnosing and troubleshooting problems on flow wrappers and vertical baggers. This Greener Tech Bite demonstrates how multiple issues can be revealed by a single impression.

Clearance

These carbons, labeled A and B, were made by the two-up, rotary sealing jaws on a flow wrapper. Both impressions show inadequate sealing pressure on the outer, operator end of the jaws. The head clearance needs to be readjusted so that the jaw faces are parallel.

Misalignment

Both pairs of jaws are also misaligned. The serrations only engage at narrow pressure points, displayed as distinct lines on the carbon impression.

Cutting Issues

The carbon for pair B shows two knife impressions, indicating a cutting issue that could be causing seal problems. A zig zag impression was made by the currently installed knife. The lighter straight impression was produced by a score mark in the anvil from a previously used straight knife. The anvil had not been changed when the new zig zag knife was set up.

Without a clean surface to cut against, the zig zag knife had to be over-adjusted. This likely caused the upper and lower jaws to bounce apart and leave the gap in the end seal that appears on these impressions just below the slot.

Additional Symptoms

Pair B also displays additional symptoms. The impression shows one consistent line where the jaws first came together, but then heavy sealing pressure on the inside end tapers and disappears half-way across. Another single line of contact appears just after the slot.

Multi-Step Problem Solving

Resolving the problems revealed by these carbon impressions required multiple steps that can’t be adequately detailed in this post and video. But this case is a good reminder of a basic problem-solving strategy: As you install new parts or troubleshoot problems, make only one adjustment at a time.

Then take another carbon impression and compare it with previous results. Did your adjustment improve the problems, make them worse, or create new issues? Through this systematic method you will get the clear feedback you need to refine each adjustment before taking additional steps, and you will also be improving your troubleshooting skills.

Discover more posts and videos about carbon impressions, including tips on the most accurate paper for your machinery and situation, on our Technical Resource Blog. And make carbon impressions a standard component of your installation, troubleshooting, and preventative maintenance procedures.

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