Coaxial cylinder measuring systems for ConTec - Viscometer
ConTec offers different coaxial cylinder mesuring systems for the ConTec-Viscometer. Each measuring system is designed for a different aggregate size.
The coaxical cylinder measuring system consists of an outer cylinder, the mix container, an inner cylinder unit and a top-ring. The outer cylinder is mounted on a rotating disk on the instrument where guide-ribs on the disk make sure that it is seated correctly. The inner cylinder wich registers the torsion-moment is lowered into the outer cylinder by a hydrolic system. The inner cylinder is constructed as a two component unit, the bottom unit wich is fixed at the mounting point of the inner cylinder and the upper unit wich is free to rotate against a load cell wich registers the torsion-moment. This arrangement of a rwo unit inner cylinder will virtually eliminate the effect of three dimensinal shearing at the bottom og the inner cylinder and therefore requires no special correction as to the bottom effect.
The top-ring is fitted over the inner cylinder. The purpose of the top-ring is to insure a constant height og the inner cylinder in relation to the sample mix in the outer cylinder. The top-ring also minimises additional shearing at the top of the inner cylinder caused by surface tension. Here is a list of all the measuring systems:
Outer radius can vary, depending on the material tested.
Ro/Ri can vary from 1.1 to 1.2 for mortar and paste.
Ro/Ri often is 1.3 for SCC (wide gap;WG).
Ro/Ri for concrete in the BML normally is 1:45.
More about some of the measuring systems:
M-170 measuring system for mortar, cement paste, cement based repair materials and grout. The system is optimised for aggregate size of 3 mm with recommended maximum aggregate size of 5 mm More information (pdf.file)
M-200 measuring system for mortar, cement paste, cement based repair materials and grout. The system is optimised for aggregate size of 5 mm with recommended maximum aggregate size of 8 mm
C-200 measuring system for concrete. The system is optimised for aggregate size of 16 mm with recommended maximum aggregate size of 22 mm.
C-240 measuring system for concrete. The system is optimised for aggregate size of 22 mm with recommended maximum aggregate size of 32 mm.