Germany's Twin Screw Sausage Extruder: Engineering Deliciousness

Twin-screw extruders are machines that use two parallel screws to mix, convey, and form materials. They are commonly used in the food industry for making sausages and other meat products, as well as in the plastics and rubber industries for processing polymers and other materials. Germany is home to several companies that specialise in twin-screw extruder technology, including Coperion, Leistritz, and GermanTwinscrewS GmbH. These companies offer a range of products and services, from extruder design and manufacturing to custom screw designs and optimisation.

GermanTwinscrewS GmbH

Since its founding in 1995, GermanTwinscrewS GmbH has established itself as a globally recognised brand, known for its first-class reputation and commitment to excellence. The company's primary focus is on plastic extrusion, injection moulding, and the petrochemical industry, but it also serves other sectors. GermanTwinscrewS GmbH prides itself on producing its own products or, in some cases, manufacturing according to customer drawings.

The GTS Engineering team is a highly qualified group that provides a comprehensive range of services. They go beyond mere customisation of screw designs and offer tailor-made optimisations, first-class training, and extensive engineering services in plastic processing. The team's GTS experts continuously strive to minimise energy consumption and enhance the effectiveness of customer machinery, ensuring that their expertise meets the unique needs of each client.

Twin-screw extruder manufacturers

Twin-screw extruders are used in a variety of industries, including plastics, food, pharmaceuticals, and chemicals. Here is a list of some prominent manufacturers of twin-screw extruders:

Xtrutech (UK)

Xtrutech, founded in 2002, is a specialist in the design and manufacture of XTS Twin-Screw Extruders, cooling systems, feeders, and ancillary equipment. They cater to various industries, including powder coatings, thermoplastics, biopolymers, and pharmaceuticals. Xtrutech offers extensive engineering services and provides OEM spares for other extruder manufacturers.

Nanjing Jieya (China)

Nanjing Jieya, founded in 2004, specializes in the R&D and manufacturing of co-rotating twin-screw extruders and highly efficient single-screw extruders. Their products include SHJ and HT Series Twin Screw Extruders, Twin Rotor Processors, and Laboratory Extruders. Nanjing Jieya caters to industries such as color masterbatch, filler masterbatch, biodegradable plastic, and recycled plastic.

Coperion (Germany)

Coperion, founded in 2001, is a leading manufacturer of twin-screw extruders, compounding machines, process equipment, and plants. They offer comprehensive services and cater to industries including plastics, chemicals, food, pharmaceuticals, and minerals. Coperion is known for its ability to provide customized solutions and high-quality process technologies.

Leistritz (Germany)

Leistritz is a family-owned company specializing in high-tech solutions for turbine, pump, extrusion, and production technology. Their Extrusion Technology division is known for its innovation in twin-screw extrusion. Leistritz has a global presence and is committed to delivering innovative, high-quality, and reliable products.

GermanTwinscrewS GmbH (Germany)

GermanTwinscrewS GmbH, founded in 1995, specializes in the design, manufacturing, and installation of high-quality screws and barrels. They offer tailor-made optimizations, training, and engineering services in plastic processing. GermanTwinscrewS GmbH serves various sectors, including plastic extrusion, injection molding, and the petrochemical industry.

Steer (India)

Steer, founded in 1993 and based in Bangalore, India, is a prominent manufacturer of Twin Screw Extruders. They design, create, and implement advanced materials platform technology for industries such as plastics, pharmaceuticals, food, and biomaterials. Steer has a global presence and is known for its innovation and advanced platform technologies.

These manufacturers play a crucial role in providing twin-screw extrusion solutions to a wide range of industries, contributing to their growth and development.

Twin-screw extruder applications

Twin-screw extruders have a wide variety of applications across multiple industries. They are used in the pharmaceutical industry to manufacture various dosage forms, such as pharmaceutical salts, co-crystals, solid dispersions, transdermal gels, solid lipid nanoparticles, and ready-to-compress granules. They are also used in the food industry for the production of food and feed products, cellulose pulps, and bio-sourced plastics and chemicals. In the military and defence sector, twin-screw extruders are used for the continuous processing of energetic materials, such as gun and rocket propellants, plastic-bonded explosives, pyrotechnics, and thermo-baric explosives.

Twin-screw extruders offer several advantages over single-screw extruders, including increased consistency in production and control of product quality, greater flexibility in processing a wide range of raw materials, and improved productivity due to continuous processing and faster start-up and shut-down. They also enable advanced automation and provide simple maintenance and cleaning.

In the pharmaceutical industry, twin-screw extruders have been used to prepare cocrystals, which are crystalline materials composed of two or more components that improve the solubility and physical and chemical stability of drug molecules. This process eliminates the need for solvents and enhances the mechanical properties of the resulting cocrystals. Twin-screw extruders have also been applied in the production of solid dispersions, which can enhance the solubility of poorly water-soluble drugs. Additionally, they are used in the preparation of transdermal gels, solid lipid nanoparticles, and ready-to-compress granules.

In the food industry, twin-screw extruders are employed in both cold and hot extrusion processes. Cold extrusion is used for gently mixing and shaping dough without direct heating, and is commonly used for producing pasta and dough products. On the other hand, hot extrusion involves thermomechanically transforming raw materials under high-temperature and pressure conditions. It is used for producing textured food and feed products, such as breakfast cereals, snacks, pet foods, and feed pellets.

Twin-screw extruders are particularly useful in the defence and military sectors for the continuous processing of energetic materials. This method offers increased safety by handling smaller quantities of explosive materials and enables the processing of a wide range of materials, including gun and rocket propellants, plastic-bonded explosives, pyrotechnics, and thermo-baric explosives. The intensive mixing capabilities of twin-screw extruders contribute to improved product homogeneity and exceptional characteristics in the final extruded products.

Twin-screw extruder structure and function

Twin-screw extruders are versatile machines used in various industries, including plastics, rubber, food, and pharmaceuticals. They are particularly effective in processing polymers, plastics, and other materials, and play a crucial role in transforming raw materials into a wide range of products.

Structure of Twin-screw Extruder:

The twin-screw extruder consists of several key components, including:

• Feeding device: This is where the material is added, usually through quantitative feeding, before being processed by the screws.
• Screws: The two screws are the heart of the twin-screw extruder and come in various types and configurations, including co-rotating and counter-rotating designs. They are responsible for conveying, mixing, kneading, and homogenizing the material.
• Barrel: The screws are encased within a heated barrel, which provides temperature control for melting and processing. The barrel is divided into multiple zones for precise temperature management.
• Die: The die is the final component where the molten material is forced through to form the desired product shape.
• Transmission device: This system controls the speed and rotation of the screws.
• Charging device: It ensures a consistent and controlled flow of material onto the screws.
• Cooling system: This system helps regulate the temperature within the barrel and around the screws.
• Vacuum system: It removes volatile components or air from the material to improve the quality and consistency of the final product.
• Electronic control system: This system allows for precise control of various parameters, such as temperature, speed, and material flow.

Function of Twin-screw Extruder:

The twin-screw extruder offers several advantages over single-screw extruders:

• Superior mixing and homogenization: The intermeshing, counter-rotating screws generate high shear forces, ensuring uniform dispersion of additives and fillers.
• High output rates and throughput: The efficient design and self-wiping action of the screws allow for continuous processing and increased production efficiency.
• Versatility in material processing: Twin-screw extruders can handle a wide range of materials, from highly viscous polymers to low-viscosity fluids, including abrasive or filled compounds.
• Precise temperature control: The multiple heating and cooling zones along the barrel are crucial for processing temperature-sensitive materials and achieving specific product properties.
• Improved melt quality: The twin-screw extruder produces a homogeneous and consistent melt, free from thermal degradation or localized overheating, resulting in better product quality.
• Reduced residence time: The continuous material flow and efficient conveying reduce the time that heat-sensitive materials are exposed to high temperatures, minimizing degradation.
• Modular design: The twin-screw extruder's modular design allows for easy reconfiguration or replacement of screw elements, making it adaptable to different processing requirements.
• Energy efficiency: Twin-screw extruders often require less energy for material processing compared to single-screw extruders, leading to cost savings and reduced environmental impact.

The twin-screw extruder's unique structure and functions make it a versatile and efficient choice for a wide range of applications across industries. Its ability to handle different materials, superior mixing capabilities, and precise control make it a preferred option for manufacturing processes.

Twin-screw extruder process

The twin-screw extruder process is a widely used industrial process that involves the plasticization and homogenization of raw materials under heat and pressure. This process is used in various industries, including food, plastic, and chemical, to produce a diverse range of products.

The twin-screw extruder machine is characterised by two parallel screws that rotate within a barrel. The raw material is fed into the barrel and transported by the screws towards the end. The screws are designed to compress and heat the material to a specific temperature range, resulting in a homogeneous mixture. This mixture is then forced through a die and cooled to form the final product. The twin-screw design enhances the mixing and kneading action, improving the overall quality of the product.

There are three common types of twin-screw extruders: co-rotating, counter-rotating, and intermeshing screws. Co-rotating screws rotate in the same direction and are used for applications requiring high mixing and kneading. Counter-rotating screws rotate in opposite directions, generating high compression and shear forces. Intermeshing screws have a unique design that maximises interaction between the screws, enhancing plasticization and homogenization.

The versatility of twin-screw extruders is evident in their ability to process a wide range of materials, from viscous molten plastics to low-viscosity fluids. They offer advantages such as superior mixing and homogenization capabilities, high output rates, and precise temperature control. This makes them highly efficient and adaptable for various industrial applications.

The process of using a twin-screw extruder involves several key steps. Firstly, the raw material is fed into the barrel through a hopper. This is followed by conveying and compression, where the screws transport and compress the material. The combination of heat and shear forces from the screws results in plasticization and melting, creating a homogeneous mixture. Intensive mixing and homogenization further enhance the process, ensuring uniform dispersion of additives. The molten material is then pumped through a die for shaping, followed by cooling and calibration to finalise the product.

Frequently asked questions