All categories
Featured selections
Trade Assurance
Buyer Central
Help Center
Get the app
Become a supplier
(1016 products available)
Hot melt extrusion machines come in different types that cater to specific applications and materials. The following types of machines are commonly used for various extrusion processes.
Single-screw Extruder
The single-screw extruder hot melt machine comprises a single screw and a barrel. This is commonly used in the food industry to process grain products such as snacks and breakfast. It features a barrel with different temperature zones and an arc-shaped sole plate. The machine comes with a cutter that has about 90 blades. It can extrude units that are well-cooked, expand, crispy, and of great quality.
Multi-screw Extruder
Multi-directional screw extruders have three screws enclosed in a barrel. They usually run simultaneously at a high speed. The three screws intertwine to form a greater space, which increases the self-cleaning ability of the machine. Multi-screw extruder units have greater productivity and can handle more viscous and fragile materials. Also, they can perform a variety of tasks, such as compounding, mixing, and homogenizing. Ideally, the multi-screw design enhances the quality of finished products. This improves production efficiency.
Single-screw Hot Melt Glue Extruder
Single-screw hot melt glue extruders are generally compact and cost-effective. They come with a barrel, screw, feeding system, and die. With a single rotating screw that moves materials forward, the unit mixes and melts materials through shear and heat. This creates a uniform product that is forced out through a die. Ideally, the unit requires minimal maintenance and is easy to clean.
Multi-screw Hot Melt Glue Extruders
Multi-screw hot melt extruder machines have two or more screws interlaced in a barrel. They are mainly designed for high-viscosity materials. The multi-screws enhance production efficiency and improve product quality. Also, they allow customization of temperature, pressure, and shear rate.
Casting Extruder
This hot melt extrusion machine model manufactures hot melt adhesives in films or polymer sheets. It comes with a single screw and a die with an open space. The die lies on a cool surface where the hot melt mass solidifies. The casting extruder unit melts materials at lower temperatures. It is mainly used to process sensitive materials like butyl rubber, ethylene vinyl acetate, natural rubber, and styrene-isoprene-styrene.
Drives:
The driving parts of the hot melt extrusion machine include a motor, reduction unit, and transmission. Their specifications vary greatly with models. They usually use AC motors are controlled with an AC ratio controller to reach a proper rotation.
Screw:
The main transporting part of the material is usually made of special alloys with great wear resistance. The length-to-diameter (l/d) ratio of the screw used for common plastic material is about 25-30. And for hot melt extrusion of specific material like food or medicine, the ration could be longer, for example, 30-40.
Cylinders:
Hot melt extrusion machine cylinders usually have a core, warming belts, or other winding-up methods. Principles like resistance and induction heating up the warmers to heat up the cylinder and warm up the material in it uniformly and consistently. The diameter of the barrel could be the same or smaller than the screw in different models and methods.
Output:
The output of a hot melt extrusion machine refers to the mass or volume of material it processes per unit of time, typically measured in kilograms per hour (kg/h) or pounds per hour (lbs/h). It can vary depending on factors such as the machine's size, design, and the type of material being extruded.
Temperature control:
A crucial aspect of hot melt extrusion machines is the temperature control system, which regulates the temperature of the extruder barrels and die. This system ensures that the material is heated uniformly and consistently throughout the extrusion process. The temperature control system may include heated barrels, cooling circuits, and temperature controllers.
Proper cleaning and maintenance of the hot melt extrusion machine is the key to ensuring its long service life and stable performance. Cleaning and maintenance are as follows:
Preparation:
Before cleaning, prepare the following tools: high-pressure washing machine, soft sponge or cleaning cloth, plastic scraper, vacuum cleaner, cleaning solution, water bucket, and other necessary equipment and tools as the manufacturer suggests. Also, make sure the area is well ventilated and away from any heat sources.
Power off:
Switch off the power supply of the hot melt extrusion machine and make sure it will not be accidentally turned on during the cleaning process.
Clean the exterior:
Use a soft sponge or cleaning cloth to soak some cleaning solutions to clean up the dirt and dust on the surface of the hot melt extrusion machine. The plastic scraper can be used to remove stubborn dirt residues. Finally, wipe the surface with a dry cloth.
Clean the interior:
Follow the manufacturer's instructions to shut down and clean the designated parts of the equipment, which usually include barrels, screws, dies, and template areas. Pay special attention when cleaning the hot melt extrusion machine die and screw. Usually, there are special cleaning solutions and tools for those parts. Refer to the manufacturer's instructions to avoid damaging those parts.
The pharmaceutical sector is profoundly impacted by hot melt extrusion devices, and numerous industries enhance their production lines with these adaptable instruments.
Pharmaceuticals:
The primary usage of hot melt extruders is in the pharmaceutical industry. Utilizing such a piece of equipment, drugs may be made more soluble through polymeric matrice design, thereby improving the bioavailability of patients. In addition, hot melt extrusion machines permit the creation of medications with complex release profiles, such as extended-release or immediate-release tablets, by enabling precise control over the composition and formulation.
Food:
It's also possible to use a hot melt extrusion machine to produce functional foods or fortified foods via hot melt extrusion that incorporate dietary supplements, probiotics, or particular food additives. Moreover, the technology behind hot melt extrusion devices has also been adopted into the food industry. Thus, such machines can now be used to make textured vegetable protein, snack goods, or even food encapsulation products, to name but a few examples of what can be produced using an extruder of this kind.
Plastic and PVC Recycling:
Hot melt extruders prove to be essential equipment in the fields of plastic production and recycling. The devices assist in the consolidation of diverse plastic resins, including PVC, to manufacture goods like pipes, sheets, and containers. Furthermore, the hot melt extrusion machine is responsible for the fusion of recycled plastics with virgin materials, which makes the extrusion process of plastics and PVC crucial to sustainable practices by decreasing plastic waste.
Chemicals:
Industries dealing with chemicals also utilize hot melt extrusion devices. Such machines are employed to coat chemical compounds, such as agrochemicals, flavors, and fragrances, so that the release profiles of these coated compounds can be regulated. In addition, the devices allow reactive blending, in which various chemical additives are blended and reacted chemically to modify the qualities of polymers.
Optics and Electronics:
Hot melt extrusion machines are also widely used in the electronics and optics industries. For instance, hot melt extruders are employed to produce optical fibers, which are vital components in telecommunication networks. Additionally, the precision mixing offered by hot melt extrusion machines allows for the production of composite materials used in electronic components such as connectors, casings, and circuit boards.
Nanotech and Biomaterials:
Some advanced material industries might also adopt hot melt extrusion technology. For example, the combination of biomaterials such as collagen and chitosan and the nanomaterials such as carbon nanotubes and nanoclays are realized with the help of hot melt extrusion technology, which leads to new advancements in material science.
Industry needs analysis
First, users need to understand their own production needs. Consider factors such as production scale, material varieties, product specifications, etc. This helps to determine what type and model of the extruder are suitable.
Equipment performance
Users should compare the performance parameters of different models, such as the power of the host, the diameter-to-length ratio, the feeding system, the temperature control system, the speed regulation system, etc. Choose a model with suitable performance to meet production requirements.
Technical support and service
When choosing an extruder, users should consider the supplier's technical support and after-sales service. Understand the supplier's service network, response time, and technical support capabilities to ensure timely support and solutions during equipment use.
Sample testing
When possible, users should request to test samples to understand the equipment's actual processing capabilities and effects. Through sample testing, users can better evaluate the suitability and performance of the equipment.
Q1: What products are made from hot melt extrusion?
A1: Hot melt extrusion machines are used to produce various products. The main sectors include pharmaceuticals, food, packaging, textiles, construction, automotive, and adhesives. In these industries, they make solid pill medical devices, filament purifier labs, and hot glue sticks, among many other products.
Q2: What are the differences between hot and cold extrusion?
A2: The differences between hot and cold extrusion lie in the temperature at which the process is conducted and the resulting properties of the extruded materials. Hot extrusion improves the material's malleability and increases resistance to abrasion and impact. On the other hand, cold extrusion creates lightweight products with high elasticity.
Q3: How do the components of an extrusion machine work?
A3: The main parts of an extrusion machine are the feeding system, heating section, barrel and screw assembly, pumping system, die, cooling system, and cutting system. Each component carries out a unique duty. Together, they ensure that raw materials are transformed into finished hot melt extruded products effectively and efficiently.
Q4: What are the levels of automation in extrusion machines?
A4: The levels of automation in extrusion machines vary from fully automated systems with integrated computer control and feedback to semi-automated and manual machines. Fully automated extrusion machines increase productivity and reduce labor.
