Sealing plastic bags quickly and reliably is essential for maintaining product freshness, preventing contamination, and improving packaging consistency. Whether you're handling dry goods, liquids, or prepared foods, a machine to seal plastic bags helps standardize output while reducing labor. At Regal Equipment, we support operations looking to scale or improve quality with used bag sealers that integrate into existing lines and boost overall efficiency. 

How to Heat Seal a Plastic Bag 

To heat seal a plastic bag, the machine applies controlled heat and pressure to the bag's opening, melting the layers together to create a secure seal. This method works especially well with thermoplastic materials like polyethylene or polypropylene. Machines like impulse sealers and continuous band sealers are commonly used in food and industrial packaging to ensure airtight, tamper-evident seals. For freezer bags or resealable packaging, the right heat level prevents leakage while preserving product integrity. 

Types of Machines That Seal Plastic Bags 

Machine Types, How They Work, and Best Applications 

• Impulse Sealer 
• Short burst of electricity heats a wire to fuse plastic 
• Light to medium-duty sealing 
• Direct Heat Sealer 
• Constant heated bars seal thicker or multilayer bags 
• Heavy-duty materials, thicker plastics 
• Band Sealer 
• Seals bags as they move through on a conveyor 
• High-volume, continuous production lines 
• Vacuum Sealer 
• Removes air and seals bag airtight 
• Food packaging, extended shelf life products 
• Portable Bag Sealer 
• Handheld or tabletop; manually operated 
• Low-volume, mobile, or space-limited setups 

How to Choose a Bag Sealer for Your Operation 

Choosing the right machine to seal plastic bags depends on your product type, packaging material, speed requirements, and sealing method. For example: 

• Use impulse sealers for polyethylene bags or light-duty applications. 
• Choose a band sealer for continuous, high-speed sealing. 
• Select a vacuum sealer if shelf life or oxygen exposure is a concern. 
• Consider a portable bag sealer for flexibility or limited space. 

You’ll also want to consider seal width, temperature control, and whether automation is needed. Regal’s used equipment inventory includes options for both semi-automatic and fully integrated bag sealing systems. 

Supported Bag Styles and Materials 

Commercial sealing machines are compatible with a wide range of plastic bag types and materials. Commonly supported materials include: 

• Polyethylene (PE) – Flexible and widely used for food products. 
• Polypropylene (PP) – Offers a crisp, clear finish with good moisture resistance. 
• Foil Laminates – Used for extended shelf life and barrier protection. 
• Nylon or multi-layer films – Provide durability for vacuum sealing or heavy items. 

Popular bag styles include pillow bags, pouches, stand-up bags, and slider resealables. Regal Equipment helps match the right sealer to your bag type and packaging needs. 

Upgrade Your Production with a Bag Sealer 

Adding the right bag sealing machine can improve packaging consistency, reduce labor, and extend product shelf life. Regal Equipment offers a selection of used bag sealers that meet a variety of operational needs — from small-batch runs to high-output production. If you're ready to improve how you seal plastic bags, explore our inventory or reach out to our team for guidance.