Standard bags
Pre-Opened Bags on a Roll – Key Technical Specifications
A pre-opened bag specification includes more than bag width and length. Film type and gauge, perforation, opening orientation, unwind direction, core diameter, bags per roll and overall roll configuration can all affect performance on a bagging machine.
Key specifications at a glance
Two bags with identical nominal dimensions are not necessarily interchangeable. For automatic or semi-automatic bagging, the complete roll configuration must suit both the machine and the product.
- bag width and length
- film type and gauge
- perforation and opening orientation
- unwind direction, core diameter and roll outside diameter
Bag dimensions, film and perforation
Allow sufficient clearance for loading and sealing without unnecessarily oversizing the package. Film selection should reflect clarity, flexibility, strength, puncture resistance, opacity, printability and sealing performance.
Perforation connects consecutive bags while allowing separation after filling. Its position and construction must support reliable feed and separation.
Roll configuration and machine fit
Opening orientation, seals, perforation, winding and unwind direction should be checked together. The core must fit the roll holder and the full roll must stay within the machine's physical limits.
More bags per roll can reduce changeovers but may increase roll diameter and weight.
Print and specification check
Clear, white/clear and opaque mailer films serve different applications. Static graphics are applied during bag manufacture, while variable data can be printed during packing.
A roll label, current specification, supplier quotation or photos of the bag and complete roll provide a practical basis for checking an alternative.
FAQ
What information is needed to quote pre-opened bags?
Dimensions, film type and gauge, perforation, opening, unwind direction, core and bags per roll are ideal.
Is bag size alone enough?
Usually not for automated processing; roll and perforation parameters also matter.
Can bags per roll be changed?
Often yes, provided roll diameter, weight and machine limits remain suitable.
Can you identify the specification from a roll label?
A label is an excellent starting point and photos can complete missing details.