Extrusion Capillary Rheometers
Introduction of Extrisopm Capillary Rheometer

Capillary rheometer is an instrument for polymer melt rheology curve testing and recording. The process is similar to extrusion and injection, that polymer melt experience a pressure when flow in a capillary tube. 


The capillary rheometer is a useful tool for the study of molecular structure and characterization of polymer processing performance. By this instrument you could observe unsteady flow of polymer melt and rupture phenomenon. You also could view on determination of melt shear viscosity, normal stress difference, melt rheology parameters such as density.


Principle of Capillary Rheometer

When the capillary rheometer works, the material in the barrel is heated and melt, and it flows through a capillary die at the bottom of the barrel after temperature is stabilized. The capillary has a diameter rang from 0.25~2 mm with different length ranging from 0.25~40mm. The screw in the barrel generates a lead to a pressure and squeeze polymer melt at a certain speed through the capillary die. 


In the extrusion process, one can measure the pressure and speed of the polymer melt at the capillary entrance and calculate different shear rate of melt shear viscosity when the capillary die parameter, and the rheological model is known.

Applications of Capillary Rheometer

  • Apparent/real viscosity test
  • Extrusion swell measurement
  • New product and formula development
  • Optimization of production technology

Features of Capillary Rheometer

  • Measuring material apparent viscosity curve using capillary die
  • Measuring material real viscosity curve by selecting different dies with different L/Ds
  • Measuring material rheological curve using slit die
  • Automatically recording diameter of extruded material and measuring extrusion swell using laser diameter measuring instrument

Specifications of Capillary Rheometer

Model

 

RCSI-20/25

Screw diameter

mm

20

L/D ratio

L/D

25

Rotating speed

rpm

120

Pressure measuring range

MPa

0-70

Capillary die diameter

mm

1 (L/D=15/20/30)

mm

2 (L/D=20/30/40)

Scale range

g

0-4100

Scale accuracy

g

±0.1

Max. temp.

0C

350

Temp. control accuracy

0C

±1

Motor power

kW

3

Total power

kW

12

Weight

kg

450

Size (L×W×H)

mm

1180×690×1720