Miscellaneous Processibility Tests

Another approach is to use a small scale internal mixer and to monitor the torque required to turn the rotors which gives a measure of the effective viscosity. These instruments are most appropriate in estimating mixing behavior, in spite of the fact that they have been used more for plastics than rubbers. 

Commercial instruments are available the Brabender Plastograph, and Plasticorder, this latter allowing use of an extruder head the RAPRA variable torque rheometer [5]. The advantages of these instruments are based on the similarity of their action to full-scale extrusion equipment and on the fact that they can be operated at shear rates appropriate for factory equipment. But because of the difficulty of matching exactly the range of shear rates which exist in full-scale plant, successful scaling-up is difficult. Elongation flow measurements have been reported by several workers, in which a sample is stretched in uniaxial tension at a constant strain rate [6]. 

Curemeters, oscillating disc, and reciprocating paddle types are forms of plastimeter that measure plasticity before the onset of cure, as well during the cure. The viscoelastic behavior of uncured rubber tested by dynamic measurement is characterized by in-phase and out-of-phase moduli and loss tangent. 

---

In any manufacturing operation, many miscellaneous supplies are needed to keep the process functioning efficiently. Items such as charts, lubricants, test chemicals, custodial supplies, and similar supplies cannot be considered as raw materials or maintenance and repair materials, and are classified as operating supplies. The annual cost for this type of supplies is about 15 percent of the total cost for maintenance and repairs. 

The functions of these laboratories usually are sterility testing of production samples, and chemical assays of raw materials for approval to use in the processes, blends or batches of raw materials before sterilization, scheduled samples of production batches, fermenter feeds, waste streams and miscellaneous sources. In many instances the analytical work for the culture laboratories will also be performed. 

The component test loop (KVK) was provided for testing the main helium components of a nuclear process heat reactor concept (PNP) at 950 °C (max. 1050 °C for short periods). The main test components were helium to helium heat exchangers, hot gas ducts, hot gas valves, bellows, steam generators, a helium purification system, helium blowers and their acoustic emissions, helium leakage, control, and other miscellaneous systems and components. The overall operation time of the KVK amounts to more than 20,000 hours at 950 C or even higher temperatures. Its main operating parameters were ... 

---