First, what is roping?
Roping is the narrowing of a web of stretch wrapping film to increase its holding strength as it is concentrated.
Roping is most often used to:
- Provide breathability for fresh products, by allowing airflow through the open space between ropes (ex: fruits & vegetables
- Provide rapid cooling of warm products to prevent condensation (ex: bakery products)
- Provide greater holding power for unusually heavy loads (ex: concrete blocks or bricks)
Generally, roping produces pallet load stability equal to that of a full wrap. The exception is when the load consists of a large number of smaller cartons/items where the rope may only touch a fraction of the surface of the load.
There are several ways to create a rope from stretch film, each involving a different application setup.
The most common method uses rollers at the top and bottom of the film web that can be positioned to push up and down against the web. This narrowing can range from a few inches at either edge to maximum reduction creating a true rope of film. Increasing the narrowing increases the strength and tear resistance. The rollers can be adjusted and locked in place by hand, resulting in the film being roped at the same rate throughout wrapping, or they can be cylinder-activated and programmed to adjust between roping and full wrapping mode in the course of the wrap. The programmed method allows the wrapper to be used for either roping or full wrap, as needed.
A second method uses either two separate rolls of narrower film, or a blade on the film carriage that cuts the full film web into narrower webs as it passes, which are then roped. These multiple narrowed ropes usually deliver more effective breathability. This method usually requires a dedicated film carriage setup.
In most cases, roping is applied in the same pattern as a full wrap would be for the particular load. However, unique, need-specific applications are also possible. One major produce grower uses roping applied for breathability but also in an X-pattern to create added downward pressure on the load, to better secure the cases to the pallet. This grower ships over long distances and needed to prevent the load from bouncing during transportation. In this case, two ten-inch rolls of film on a dedicated carriage are used to rope in a pattern that maximizes both breathability and stability.
There are a wide range of film gauges that can be used for roping. And because roping increases the holding power of the film, it is usually possible to downgauge and achieve comparable load results while reducing film cost.
Roping is a cost-effective option available with most of Orion Packaging’s automatic and semiautomatic wrappers.