Types of Tube Sealing

August 1, 2021

When choosing tube filling equipment for plastic tubes, it is very important to understand the various types of tube sealing options available.  Tube filling machinery comes with hot-air sealing, ultrasonic sealing, impulse sealing or hot-jaw sealing options.  Matching the type of squeeze tube with the correct tube sealing equipment is very important to ensure strong, professional tube seals.  Each tube material behaves differently so what works well for a mono layer polyethylene cosmetic tube, may not work so well with a multi-layer COEX tube.  Depending on the industry for a given product, such as cosmetic tubes, personal care tubes, pharmaceutical tubes, or household & industrial tubes, choosing the correct tube filling & sealing equipment can be challenging.  Lets take a look at the two most popular options currently used in the tube packaging industry today.

Hot Air Tube Sealers

The most popular tube sealing machinery option is hot-air tube sealing.  With this system hot air is generated and blown into the open end of the plastic or laminate tube.  This heated air penetrates the plastic tube wall heating the material enough to make it soft and pliable.  A set of tube sealing jaws then crimps the softened plastic to weld the open end closed.  The primary advantage of this tube sealing technology is it’s speed.  Another advantage is hot air sealers work with the largest range of laminate or plastic tubes.  Whether the tube material is LDPE, MDPE, HDPE, PP, Mono layer or multi-layer with or without EVOH barrier protection, hot air tube sealing should work.  A disadvantage however is the need for specific hot air nozzles sized to each diameter tube that is filled and sealed.  This will add to the cost of change parts needed for the tube run.  The cost of format parts are minimal however when factored over the production run size at higher throughput.  We recommend this style of tube filler if the production run sizes are greater than 1,000 tubes.  Machinery options start around $15,000, view our new tube sealing machines.

Ultrasonic Tube Sealers

Ultrasonic tube sealing is another popular option found in the packaging industry today.  Standalone tube sealers using ultrasonics are popular for small volume tube runs.  Tube filling machinery can also be retrofitted with ultrasonic tube sealing systems as an alternative to hot air sealing.  With ultrasonic tube sealing, plastic and laminate tubes are sealed by high frequency vibration of an ultrasonic sealing horn.  This high frequency vibration generates intense heat at the tube wall which causes the polyethylene tube plastic to soften.  The open end of the plastic tube is held closed under pressure from the sealing horn and matching sealing anvil, thus forming a strong weld.  Advantages of sealing tubes with ultrasonic technology are the ease of use, no need for custom-made size parts, and ability to seal through product contamination in the seal area such as happens when overfilling a tube with product.  The disadvantage however is lower tube sealing speed compared to hot-air sealing.  Ultrasonic tube sealers usually seal tubes at only 5 units per minute.

The Whole Package has over 2 decades of experience with sealing tubes of all materials, shapes and sizes.  We offer new tube filling machinery as well as used tube filling equipment.  Call or email us with any questions, we are always happy to talk about tube filling and sealing machine options for your next product launch.