A new generation of melt index testers from Instron reliably perform a variety of tasks, from monitoring incoming materials to product development and process control.

The compact, manually operated MFi5 is suited for fast and reliable measurements via presets, while the modular MFi7 is designed to accommodate an increasing volume of testing.

Both models support test temperatures from 50° to 450°C (122° to 842°F) and are equipped with test weights from 0.1 to 21.6 kg (3.5 oz to 47.6 lb). A piston travel transducer resolution of 0.005 mm and piston displacement accuracy up to 0.02 mm enable particularly accurate measurements. The two systems cover the entire range of requirements for standard melt index tests in accordance with ISO 1133 and ASTM D1238, methods A, B, and C, according to Instron.

Optional equipment for both melt index testers includes a motor-driven cutting device for precise, repeatable separation of the extrudate by time (with 0.01-second accuracy) or position; automatic die plug opening; special pistons for high-flow materials; and corrosion- and wear-resistant steel cylinders, pistons, and dies.

A motorized lifting device that handles the automatic, operator-independent application of test masses comes standard with the MFi7. Cleaning is facilitated with an easily removable die retainer, and an automatic material compaction system operates at constant pressure, providing added accuracy and repeatability. Automated purging and cylinder cleaning allow effortless, rapid emptying of materials remaining in the cylinder after testing is complete. Load-cell controlled compaction and emptying phases avoid operator influences, thus further boosting laboratory efficiency and the consistency of test results. Options for the MFi7 melt index tester include a manual mass selector for added operator safety and a safety cover that prevents unintentional access to the machine's test areas.

Three inputs via the user interface of the control panel enable quick, easy creation of test methods. Melt index test results are displayed in the form of real-time graphs. Live help offered on each screen reduces the amount of training required for new operators, and helps avoid costly errors during testing, said Instron.

The MFi series is supported by Instron's Bluehill Melt software, which is equipped with easy-to-understand icons and workflows to simplify user training and test setup.