Online measurement of the rheological behavior of PBX in a continuous process.

For continuous processing of explosives in a screw extruder, it is necessary to know the rheological behavior, the relationship between shear rate and shear stress, as well as between shear rate and dynamic viscosity, which are dependent on throughput and temperature. With this data from the online rheometer, especially the dynamic viscosity, conditions are given for running an extruder with PBX, e.g. PBXN-106 or PBXW-109, or plastic bonded explosives such as the C4-type or the C4 substitute on Hycar-basis. A report will be given on the design of the online rheometer adapted to a corotating twin-screw extruder for measuring constant data such as dynamic viscosity, which is an important parameter for quality control. The influence of shear stress versus shear rate, as well as dynamic viscosity versus shear rate will be discussed. With an online rheometer the conditions will be given for running PBXs or plastic bonded explosives in large production extruders having a high, continuous thr oughput and high quality standards