A Quick Primer on Heat Sealers

Our latest blog post is a refresher on the general basics of heat sealers.  There are many types of sealers and choosing the right one may be overwhelming without a few basic points.  We discuss four key characteristics of sealers to help you determine which best fits your application.

Function

Impulse sealers require no warm up time and seal by applying a pulse of energy to the sealing area, followed immediately by cooling.  Impulse sealers only use power when the jaw is lowered.  We recommend an impulse sealer for any thermoplastic material such as polyethylene (PE) or polypropylene (PP) which requires a lower seal temperature. Impulse sealers are easy to use (no warm-up time), economical (electricity used only during sealing process), and safe (no component is always hot).

Direct heat (constant heat) sealers maintain constant heat in both jaws.  Direct heat sealers use power as long as the machine is turned on.  As a result, direct heat sealers possess better heat penetration in order to seal thicker materials.  We recommend a direct heat sealer for materials such as coated aluminum foil, poly cello films, gusset bags, coated Kraft papers, waxed paper, cellophane, mylar, coated PP, and other thicker materials.  Direct heat sealers cannot seal polyethylene.

Feel free to read our previous posts comparing impulse vs. direct heat sealers

Size

The size of the sealer depends on the width of the material to be sealed.  We usually recommend adding one inch to the width of material to be sealed to determine sealer length for easier handling.  Cutters on the sealer usually trim at slightly less than width of the sealer arm.

Speed

See below for a general guideline on speed (packages per minute) of our impulse and direct heat sealers.

Width of Seal

Heating elements are made of nichrome (nickel-chromium) and determine the width of the seal.  There are two types of heating elements: round or flat which are interchangeable in most sealers. The round wire is mainly used to cut and seal with no excess material above the seal.  Depending on the width of the flat wire element, sealers are available in 2-3mm, 5mm, 8mm, or 10 mm. Some sealers are equipped with two heating elements for faster heat penetration making them ideal for sealing thicker materials.