The Melt Flow Rate Apparatus is an instrument used to determine the flow properties of thermoplastic polymers in their粘流状态. It measures the melt mass flow rate of thermoplastic resins and is suitable for testing plastics with low melting temperatures such as fluoropolymers, nylon, engineering plastics, polyethylene (PE), polypropylene (PP), polyformaldehyde (POM), polystyrene ABS resin, polycarbonate, and others. The determination of the melt mass flow rate is achieved through automatic sampling and weighing, followed by calculating the volume flow rate using a formula. The final results of the measurement are displayed on the instrument's LCD screen and output by a micro printer. The instrument offers accurate data measurement, simple operation, clear visibility, and stable performance.
Melt Flow Rate Meter Structural Principle
The Melt Flow Rate Apparatus is an extrusion plastometer. It melts the test material under specified temperatures using a high-temperature furnace. This melted material is then extruded through a small hole under the load of a specified weight. In the plastic production of industrial enterprises and research units, the "melt (mass) flow rate" is commonly used to represent the physical properties such as fluidity and viscosity of high polymers in the molten state. The melt flow rate refers to the average weight of the extruded samples converted to a 10-minute extrusion volume. This instrument consists of a furnace and a temperature control system, installed on the body and base. The temperature control section uses a single-chip microcomputer to adjust power for temperature control, featuring strong anti-interference ability, high temperature control accuracy, and stable control. The heating wire in the furnace is wound around the heating rod in a certain pattern to minimize the temperature gradient, meeting the standard requirements.
The operation steps for the melt flow rate instrument are as follows:
Insert the mold into the feed port and press it down with the feeding rod until it contacts the mold stopper.
Insert the piston rod (assembly) into the cylinder from the top opening of the hopper.
③ Power on the device by toggling the power switch on the control panel. Once the power indicator light illuminates, set the constant temperature point, sampling time interval, sampling frequency, and loading load on the test parameter setting page. After accessing the main test page, press the "Start" button. The instrument will begin heating. Allow the temperature to stabilize at the set value and maintain the constant temperature for at least 15 minutes.
After 15 minutes of maintaining a constant temperature, put on the prepared gloves (to prevent burns) and remove the piston rod. Then, using the hopper and filling rod, sequentially load and compact the pre-prepared sample into the cylinder. The entire process must be completed within 1 minute. Afterward, reinsert the piston into the cylinder. Four minutes later, apply the standard test load to the piston.
⑤ Scraping, available in three scraping methods:
Automated Scraping: Place the sampling dish below the discharge outlet. When the piston rod descends to the lower ring mark on top of it being level with the upper surface of the guide sleeve, press the "RUN" button. The scraper will automatically scrape the material according to the set number of scrapes and sampling time intervals.
B. Manual Scraping Place the sampling dish below the discharge opening, set the sampling method to manual scraping. When the piston rod descends until the lower circular mark on it is level with the upper surface of the guide sleeve, press the "SPIN" button and rotate the manual knob to scrape the material.
C. Cancel manual knob during automatic scraping.
⑥ Results Calculation: Place 3-5 bubble-free strips on the balance and weigh them separately (balance, accurate to 0.01g). Take the average, enter it on the test homepage and press the enter key. The instrument will automatically calculate the melt flow rate value and display it on the main interface. Select to print the results, print the test report, and complete the test.
