One of the most popular and inexpensive methods of closing paper bags is to sew them shut. Here at Inpak Systems, there are two specific types of bag sewers to choose from: portable and fixed head sewing systems. We’re going to dive into each type of paper bag sewing machine to help you better understand the difference between them.
Portable or Handheld Bag Sewers
Portable bag sewers – sometimes called handheld – are usually used in entry-level bagging operations (<5 bags/minute), when there are just a few bags to sew at a time, or where a fixed sewing head is not suitable (i.e. out in the field).
A portable sewer typically uses a single thread, but for textile bags a dual thread is normally used. A spring-loaded suspension unit can be used to reduce fatigue. As the bagging operation grows, a portable sewer can be mounted on a pedestal above a conveyor.
Fixed Head Bag Sewer
Fixed sewing heads are mounted on pedestals above a horizontal bag closing conveyor. Fixed head bag sewers are manually fed and designed to run 24/7 and on higher volume bagging operations (up to 20 bags/minute). Fixed head bag sewers use a dual thread stitch. They can be integrated into fully automated systems. Tape coders and tag placers are often added to label the bags
Bag Sewer Finishing Methods
Regardless of the type of paper bag sewing machine you choose, there are also two primary finishing methods used to close a bag: plain bag sewers & tape bag sewers.
- Plain sewers close paper bags with a single thread stitch (portables) or a dual thread stitch (fixed heads).
- For fine powders, where leakage may be an issue, a bag with a top that is folded over before sewing closed can be used.
- Tape sewers close paper bags with crepe tape applied over the bag top before being sewn closed. The crepe tape produces a nice finished top and reduces product leaking.
- With real fine products, where leaking is a major issue, a filler cord can be added to “seal” the needle holes.
Fill Your Packaging Needs with Inpak Systems
How can Inpak Systems help you with your industrial packaging needs? Contact us at 1-608-221-8180 or [email protected] with any questions that you may have or to discuss your business needs. You can also learn more with our Bag Sewers YouTube playlist.