Pressure capillary viscometer

Rheological and processability behaviors were studied in a Monsanto processability tester (MPT), which is an automatic high-pressure capillary viscometer. The entire barrel and capillary are electrically heated with a microprocessor-based temperature controller [14], The... 

A computer-controlled rheology laboratory has been constructed to study and optimize fluids used in hydraulic fracturing applications. Instruments consist of both pressurized capillary viscometers and concentric cylinder rotational viscometers. Computer control, data acquisition and analysis are accomplished by two Hewlett Packard 1000 computers. Custom software provides menu-driven programs for Instrument control, data retrieval and data analysis. 

DIFFERENTIAL PRESSURE CAPILLARY VISCOMETER AS AN IN-LINE VIsensITV DETECTOR... 

In a pressure capillary viscometer, such as a rheological die, pressure is used to force fluid through a capillary tube at constant volumetric flow rate Q, as shown in Figure 6.4. The pressure difference AP is measured between points A and B spaced apart a distance 1 along the tube. The basic rheological equations are as follows for shear stress and shear rate taken to be very near the wall in a tube of radius r ... 

Figure 6.4 Illustration of two pressure capillary viscometers, or rheological dies.

The latter method is a generic one for a wide range of capillary viscometers. A separate method directed to a specific commercial high-pressure capillary viscometer is currently under development in ASTM Committee D.02, Subcommittee 7. 

The main focus of the measurement programme was the rheological measurements with the high-pressure capillary viscometer. In addition, a number of measurements were performed with the aim of permitting statements about the dispersion state (pyrolysis, microscopic investigations) and determining (conductivity measurements). 

To this end, the dynamic viscosity of the various specimens was measured with a high-pressure capillary viscometer at various shear rates. 

J.H. Southern, R.S. Porter, The properties of polyethylene crystallized under the orientation and pressure effects of a pressure capillary viscometer. J. Appl. Polym. Sci. 14(9), 2305-2317 (1970)... 

Miller et al. have recently reported infra-red dichroic data obtained for high density polyethylene crystallised under the orientation and pressure effects of a pressure capillary viscometer. Their data for a number of crystalline bands (including the 1894 cm" absorption) showed that the crystal c-axes were almost perfectly oriented (f 1) in the initial extrusion direction. The amorphous orientation functions were generally lower, but corresponded to an extension ratio between 2 and 7 when compared with the above results of Read and Stein and of Glenz and Peterlin. Further evidence was also obtained for the relatively high orientation of the amorphous component of the 2016 cm" band (U = 0-66-0-72). 

Ahhot, S.D. Yau, W.W. (to Dupont). Differential pressure capillary viscometer for measuring viscosity independent of flow rate and temperature fluctuations. U.S. Patent... 

The combined effects of pressure and orientation on the melting behavior of PE have recently been investigated using a pressure capillary viscometer (207). Although pressures of only 1900 atm could be realized in this study, the melting points and superheatibility (see Fig. 26) of this... 

Southern, J. H., and R. S. Porter, Polyethylene Crystallized Under the Orientation and Pressure of a Pressure Capillary Viscometer—Part I, J. Macromol Sci. Phys., B4, 541-556, 1970. 

---