Blown stretch film

A buying guide sends irregular loads to blown film.³ That means mixed cartons that don't stack square, drums and pails, bundled metal, parts in totes with edges, and anything that has to survive a forklift tine. The film's toughness is what it is sold on: it stretches round an edge where cast film would start a tear.

Blown film is noisier to unwind, which some wrapping halls notice. It is less clear, so a label under three layers is harder to read. And because blown is the smaller share of film made, about 20 to 30 percent,¹ it is quoted on its own terms. If your loads are square cases of one product, cast will usually do the same job.

Hand wrappers rarely stretch film far, so the qualities that matter are the ones that work at low stretch: grip on the load, a tail that stays put without tucking twice, and a web that doesn't split when the roll catches a carton corner. Blown film does well on all three. That is why many mixed-load docks, such as grocery distributors, building suppliers and parts warehouses, keep blown hand rolls even though their machines run cast.

Blown machine rolls are made in the usual 20 inch width and wider. They suit wrappers handling mixed products, sharp loads or cold rooms, where breaks on cast film cost more in downtime than the difference in film price. Ask for the stretch rating, since blown films often run at somewhat lower pre-stretch than cast.

Blown film's toughness is useful in freezers and chillers, where film is stiffer and tears more easily.

Why is blown film so loud?

The way it is made, cooled slowly as a bubble, gives it a different surface and structure; it crackles off the roll. It is a nuisance in some wrapping halls and nothing more.

Is blown film the same price as cast?

We don't publish prices; ask for both in the request and compare them on the loads each one wraps, not on price per roll alone.

Do I need a heavier gauge in blown film?

Often the reverse: blown film's toughness can let you hold a sharp load at the same gauge where cast would tear. Start at the gauge the chart gives and test.

Which gauges does blown come in?

From light to heavy, by hand and by machine. It is chosen most often at the heavier steps, where puncture resistance earns its price.

Is blown film more stretchy?

Usually a little less, but tougher.

• Cast stretch film

  Clear, quiet

  For square, uniform loads.

• Cast vs blown

  Guide

  The whole comparison.

• Automotive parts

  Sharp loads

  Where blown film earns its place.