Page 113 - QRedition5.0 062021

Quality Requirements Edition 5.0 European Enamel Association

larger surface within small space, the test sheet is bent to give a cylinder. The results by Helpful information can be achieved with regard to the judgement of fluidity of muds in
this are more accurate. closed pipes (pump feeding).

The application weight and the observations made of the flow, can be, in a limited way, the Unsuitable for the judgement of application properties of enamel slips are the DIN or Ford-
criteria of the application behaviour of the slip. beaker and the Lehmann-Viscosity meter.

2. Enamel slip gauge
The PRINCE enamel slip gauge has been developed in order to characterize the
consistency of the slip quickly, without weighing. The device allows comparisons of slips
of the same type and consists of a blade of stainless steel, sized 27 • 4 cm with ten holes
with steadily increasing diameters from 5 - 14 mm.

Method of operation:
Use the gauge to stir the slip under test, then lift out the blade vertically with uniform
velocity. By draining the slip off the blade, the holes open up, incipient with the lowest,
the biggest. The number of open holes can be of information about the application
behaviour.

The test method is among other things affected by varied manual draw-out velocities.

3. Slump test
The slump test belongs to the more costly but also more exacting test methods. The spread
of a fixed volume of slip on a panel scored with concentric rings is measured. The test pro-
vides information about viscosity and thixotropy. Both properties are covered by one sum
in which the spreading of watery slips is predominantly affected by its viscosity. An existing
thixotropy affects the test results of viscous enamel slips.

Method of operation:
A metal cylinder is placed in time, no real statement can be made about the application
behaviour of enamel slips. It has been tried again and again to change the design of outflow
cups, enabling them for mud processing, but non representative or reproducible results
have been achieved.
© EEA2020 page 113
EEA2020