Adhesives and Equipment Options for Different Applications
Many manufacturing industries require the use of hot melt adhesives. Packaging, product assembly, cable assembly, automotive interiors, woodworking, and insulating glass are just a few of the applications.
The hot melt process involves heating a thermoplastic polymer and applying it to liquid parts and components as an adhesive. As the plastic cools, it solidifies, forming a strong and secure bond. Hot melts can produce bond strengths that are similar to welding
depending on the binder and tools used.
Many of today’s complex manufacturing processes require the use of hot melt adhesive. Packaging, product assembly, woodworking, binding, cable assembly, insulating glass, automotive interiors, RV lamination, solar panels, advanced composites, and other applications are just a few examples.
Unplanned downtime and production loss can cost businesses thousands of dollars each year, regardless of the application.
Hot melt adhesives provide excellent bonding strength in a short time as solid materials (at room temperature) without solvents or water. The hot melt adhesive can penetrate the material surface and form a strong bond once it has been heated. The bond caused by the
high temperature during the application process may be similar to welding depending on the bonding material.
Types of Adhesives and Equipment Parts
Choosing the right adhesive and equipment for the job can help you avoid costly downtime and production loss due to adhesive failure. By ensuring that the nozzles, hoses, and modules chosen are appropriate for the application, you can increase process speed,
reduce waste, and reduce bonding errors. Typical hot melt equipment consists of three main parts: hose, module and nozzle.
Hot Melt Hoses: The molten adhesive is delivered to the nozzle through these tube-like structures. These flexible, reinforced hoses must be designed specifically for the chosen module and nozzle. Hose selection errors can compromise component reliability and
cause issues like breakage and clogging.
Hot Melt Modules: The hot melt adhesive system’s heart is the module. It’s a molten glue dispensing valve. A nozzle also controls the amount of liquid applied by the module. The module, like any other component, must work with the rest of the system, including
the hose and nozzle. The module must also dispense the correct adhesive type and be appropriate for the adhesive application mode.
Hot Melt Nozzles: The nozzle has the greatest impact on the adhesive application’s quality, consistency, yield, and performance. You must consider several factors when choosing the right nozzle for the job, including glue pattern, number of holes, hole diameter, nozzle angle, and gun style.
To ensure optimal bonding performance, it is critical to use the appropriate adhesive and equipment parts. Different types of thermoplastics can be used for hot melting, each with different properties that can be used for different applications. The following are some of the most common adhesives:
EVA (Ethylene Vinyl Acetate): This thermoplastic polymer performs well at temperatures ranging from -22°F (-30°C) to 175°F (80oC). The most common type of hot melt is EVA, which is used extensively in packaging and product assembly.
PA (Polyamide): PA is more expensive than EVA, but it has a higher heat resistance. This polymer is widely used in the woodworking, automotive, and electrical industries, with service temperatures ranging from -76oF (-60oC) to 266oF (130oC).
PP (Polypropylene): Polypropylene is a thermoplastic polymer that is frequently used in adhesive spray formulations. It is lightweight, long-lasting, and chemically resistant. Polypropylene works in temperatures ranging from -22°F (-30°C) to 230°F (110oC). PP is
used in a wide range of applications, from consumer packaging to medical adhesive bonding, due to its diverse properties.
PUR (Polyurethane): PUR melts are non-toxic, quick to cure, and temperature and weather resistant. This adhesive absorbs a small amount of moisture before going through a chemical reaction that solidifies it and forms a strong bond. PUR sticks to glass, plastic, metal, and wood, making it ideal for furniture, shoes, boat construction, and other applications.
The Right Adhesive for Efficient Production
While the hot melt process appears to be simple on the surface, there are several adhesive and equipment-related factors that must be carefully considered for the bonding application to perform at its best. Once the needs are understood, it will be much easier and more
accurate to find an option that offers an effective solution.
Pumps and Pump Systems for Cold Systems
A wide range of adhesive viscosities and application pressure requirements are met by liquid adhesive pump systems and pressure vessels. Low, medium, and high pressure cold glue pump systems and cold glue application equipment are available, as well as single
and multiple glue gun outlets. There are a variety of mounting options available to make it simple to integrate into new or existing production lines.
Liquid Adhesive Pumps and Pressure Tanks
A wide range of adhesive viscosities and application pressure requirements can be handled by liquid adhesive pump systems and pressure vessels. Low, medium, and high pressure cold glue pump systems and cold glue application equipment are available, as well as
single and multiple glue gun outlets. Cold adhesive dispensing systems have a variety of mounting options that make them easy to integrate into new or existing production lines.
References
• https://www.nordson.com/en/divisions/adhesive-dispensing-systems/products/pumps-and-pump-systems
• https://www.graco.com/us/en/in-plant-manufacturing/products/sealants-adhesives/sealant-supply-systems-pumps.html
• https://www.thomasnet.com/insights/how-to-choose-the-appropriate-adhesive-equipment-parts-for-yourapplication/?_ga=2.42818983.387078201.1652775046-67476456.1652775046
•Photos: shutterstock.com / pixabay.com
Translation and Compilation by: B. Serhat Cengiz
