Operation Guide for Hot Melt Extruder for Medicine and Pharmacy: Key Points for Safety and Efficiency

1. What is a hot melt extruder for medicine and pharmaceuticals?

A hot melt extruder is a device that converts raw materials into uniform products through heating, mixing and extrusion processes. In the pharmaceutical field, it is mainly used to combine active pharmaceutical ingredients (API) with polymer carriers and other excipients by melt mixing. This process does not require the use of solvents and is a kind of "green" pharmaceutical technology.

2. Preparation before operation

Adequate preparation is not only the basis for safe production, but also the prerequisite for ensuring stable product quality. Before using a hot melt extruder, pharmaceutical factories must systematically complete a series of preparations, which are much more complicated than simple equipment inspections and involve comprehensive preparations in multiple dimensions such as personnel, equipment, materials, and environment.

Personnel training and qualification confirmation are the first steps before operation. Operators of hot melt extruders must fully understand the structure, performance, operating procedures and safety precautions of the equipment, ensure that they have relevant skills and knowledge, and avoid safety accidents caused by improper operation. Personnel training should include but is not limited to: equipment structure and principle, normal operating procedures, emergency handling, cleaning and maintenance procedures, GMP specification requirements, etc. After training, the operator's competence must be confirmed through assessment, especially for the operation of new models of equipment, which must not be operated based on experience.

Before starting the machine, check whether all components are intact, such as screws, barrels, heaters, transmission devices, etc., to ensure that the equipment is not damaged or loose, and avoid failures during operation. For OMEG series equipment, it is also necessary to check the cleanliness of the extruder's knife disc, feed port, extrusion port and roller to ensure that there are no foreign objects inside.

Equipment inspection should establish a standardized inspection list, including:
Mechanical system: screw wear, barrel inner wall condition, transmission system lubrication, etc.
Heating system: working status of heaters in each temperature zone, thermocouple accuracy, etc.
Electrical system: power connection, grounding condition, safety protection device, etc.
Control system: parameter setting, sensor calibration, emergency stop function, etc.
Material preparation should pay attention to:
Dryness of raw materials (moisture content may affect the extrusion process)
Particle size distribution (affects mixing uniformity and fluidity)
Pretreatment requirements (such as screening, premixing, etc.)
Batch consistency (ensure the stability of the production process)
Parameter preset and process verification are the key to ensuring product quality. Set operating parameters such as extrusion temperature, extrusion speed, pressure and die power according to the instructions in the equipment manual. Temperature setting is particularly critical. According to the functions of different sections, a saddle-type temperature setting of "high, medium and low in the front and high in the back" or a step-type setting that gradually increases from front to back is usually adopted.

Equipment inspection and material preparation table:

3. Key points of safe operation

As a precision equipment operating at high temperature and high pressure, hot melt extruders are extremely important for safety control during operation. A slight operating error may cause serious personal injury or equipment damage, especially in the pharmaceutical field, and is also related to the quality and safety of the final drug. Mastering the key points of safe operation of hot melt extruders is a basic quality that every operator must possess, and it is also an important guarantee for the safe production of pharmaceutical companies.

Temperature management is one of the most critical control factors in hot melt extrusion operations. Before starting the equipment, it must be fully preheated so that the barrel, screw and other components are evenly heated to the set temperature. During the preheating process, the requirements of the equipment manual should be followed to avoid damage to components due to excessive heating. The temperature settings of different sections need to be carefully adjusted according to the material characteristics and process requirements.

Temperature control needs to pay attention to:
Feeding section temperature: It should be high enough, because the material temperature here is much lower than the displayed temperature, and a large amount of external heat is required to start the plasticization process.
Metering section temperature: The purpose of setting is to stop external heating and transfer excess heat to prevent material degradation.
Head temperature: It should be higher to slow down heat loss, but too high will lead to lower melt pressure.
Die temperature: It is mainly for molding, and it is adjusted according to the cross-section of the product. Too high will lead to uneven expansion.

Personal protective measures are the basic guarantee to avoid operator injuries. Appropriate protective equipment must be worn during operation, such as anti-scalding gloves, goggles, work clothes, safety helmets, etc., to prevent accidental injuries such as burns and scratches. It is particularly important to avoid direct contact with high-temperature parts such as barrels and screws during operation. The temperature of these parts may be as high as 300°C or above, and contact will cause serious burns. If you need to contact high-temperature parts, you must use special tools or ensure that the protective equipment is intact.