The MI40 from Goettfert is an amazing instrument whose primary purpose is to measure the melt flow index (MFI) of a polymer depending on the temperature and load chosen. MFI has applications in comparing densities of PE or determining if your part has been oversheared or improperly dried during or prior to manufacturing. If you’re interested in ensuring the quality of your product between lots or want to research if a new polymer will flow through your extruders or injection molders, please visit our Testing page or contact Carl Thomas at