How packaging materials and design affect VFFS & HFFS line efficiency
Vertical form fill seal (VFFS) and horizontal form fill seal (HFFS) lines run at speed, and at speed, small problems can quickly become big ones. A film that tracks inconsistently, seals poorly, or causes frequent stoppages slows production and adds cost at every point in the form of waste, rework, engineer time and missed output targets. In most cases, the root cause is not the machine. It is the film.
Flexible packaging films for form fill seal operations are often selected on price or availability, with machinability treated as secondary. That approach tends to be a false economy. The properties of a film determine how it behaves on the line, and a specification that is not matched to the machine and product will create friction.
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How film properties affect machine performance
The physical characteristics of a flexible film have a direct bearing on how reliably a VFFS or HFFS line runs. Stiffness affects how the film forms around a collar or former; a material that is too rigid or too limp for the application will track inconsistently and cause misfeeds. Thickness tolerance matters too – even small variation across a reel can alter tension and lead to registration errors or sealing problems over a production run.
Coefficient of friction is another variable that gets less attention than it deserves. A film with the wrong surface friction for a given machine will either drag or slip, disrupting the feed rate and causing stoppages. For flexible films for VFFS operations in particular, where the film is drawn continuously over a forming tube, consistent friction across the reel is not optional.
Film optimisation for packaging lines means accounting for all of these properties together, not treating them in isolation. A film that performs well on one line may behave differently on another running at a higher speed or different temperature. Matching specification to the specific machine and application is where the real efficiency gains are found so it’s important to seek advice from knowledgeable flexible film manufacturers in the UK.
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Seals, print and the details that cost you downtime
Seal performance is where many line efficiency problems become visible, even when the underlying cause lies elsewhere. Weak or inconsistent seals can result from a film whose heat-seal layer is not compatible with the machine’s sealing parameters, or from variation in the film surface that prevents consistent contact. Either way, the result is the same: product at risk, line stopped and output lost.
Heat-seal issues are made worse when the film specification has not been validated against the sealing temperatures and dwell times of the machine in question. Custom flexible films for VFFS and HFFS lines are engineered with those parameters in mind from the outset, rather than adapted from a standard specification after problems arise.
Print quality is another factor in line efficiency that is easy to overlook until it causes a stoppage. On form fill seal lines, registration marks are what the machine uses to position the film accurately before cutting and sealing. If those marks are unclear, poorly contrasted or inconsistently printed, the machine eye struggles to read them – leading to misregistration, wasted film and interrupted runs.
The inks and coatings applied during printing also affect the surface properties of the film, including friction. A print finish that alters the coefficient of friction from the specified value will affect how the film feeds, regardless of how well the substrate itself has been selected.
Working with a print partner who understands the relationship between print and machinability is as important as working with one who can deliver visual quality.
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Designing for the line, and for the future
The most effective way to avoid film-related efficiency problems is to address specification early. When packaging film suppliers and food manufacturers collaborate at the design stage, the film can be engineered around the machine, the product and the production environment rather than adjusted to fit.
Bespoke packaging films for automation account for the specific demands of a line: forming geometry, sealing method, speed and the nature of the product being packed. That level of detail makes a material difference to HFFS packaging line efficiency and VFFS packaging line efficiency alike, particularly in high-volume operations where stoppages have a significant cumulative cost.
Sustainability is also a consideration that is best built in at this stage. Recyclable and mono-material film structures have specific handling characteristics that need to be understood and accounted for in the film design. Retrofitting a sustainability requirement onto an existing specification is more difficult and expensive than designing for it from the start.
Terinex Flexibles has been supplying flexible packaging solutions for food manufacturers in the UK for over 20 years. As HFFS film suppliers in the UK with in-house flexographic print capability, Terinex Flexibles works with food brands and manufacturers to develop films that are optimised for their lines, machines and products. From standard options to bespoke packaging films for automation, the technical team is on hand to help get the specification right before production begins – not after problems emerge.
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How packaging materials and design affect VFFS & HFFS line efficiency
Contact our team for high-quality VFFS and HFFS packaging solutions.