manufacturer:      Bohlin

model:                  CVO 50

CVO

Rheological instruments backed with rheological experience

A practical rheometersystem in your laboratory.Whether your needs are for high use, busy Quality Control or for bespoke user-defined measurement procedures, the BohlinCVO is an instrument you can rely on. Compact and spill resistant with a membrane keypad the CVO’sdesigned for easy set up and control. The CVO accepts interchangeable temperature control units and the options for extended shear rate and quantitative normal force arealso available.

Complete rheology

• Integrated, computer controlled systems

optimisessensitivity and minimisescabling and inter-connections

• Automatic gap zeroing and adjustment

withan integrated axial force sensor and precision stepper motor to control the gap precisely, easily and reproducibly

• Thermal mode

automaticallycompensates for expansion during temperature sweeps and ensures that the gap remains constant

• Axial force mode

allowsa pre-programmed normal force to be applied to the test sample (available with normal force option)

• Sample loading

iscontrolled using programmable descent rate to limit normal stresses imposed on the sample

• Unique air bearings

robust, porous design which is completely impervious to particle contamination. These bearings offer low inertia for oscillation data, low drag for viscometrydata and negligible rotational torque errors

• Wide torque range and measurement

accuratelyachieved because the motor design delivers a linear torque response over decades without drift. Low motor inertia and drive circuitry offer rapid transient response and wide operating frequency range

• Microstrainposition sensing

witha digital resolution of 107 parts per revolution and no signal drift to enable analysis of even weakly structured materials within their linear response region

• Broad speed range

withhigh resolution position sensing to ensure excellent performance across the entire speed range

Applications

• Coatings
• Adhesives
• Cosmetics
• Personal care products
• Foods
• Composites
• Petrochemicals
• Polymers
• Pharmaceuticals
• Asphalt

Software to make it happen

Windows^TMcompatible software is provided with every BohlinCVO delivering the ease of use and user-defined flexibility professionals around the world have come to expect.

Viscometrymodemeasures viscosity as a function of shear stress or shear rate. Measurements include single value of shear rate (or stress), table of shear rates (or stresses), continuous shear rate (or stress) ramp (including yield stress) and complex shear rate (or stress) profile. Temperature control can be isothermal (time sweep), or follow defined gradients or step changes.

Creep modemeasures the creep compliance and recoverable compliance as function of time. User defined sampling modes can be set. Zero shear viscosity and yield stress can be determined.

Oscillation modemeasure the dynamic viscoelasticproperties as a function of frequency, Measurements include single frequency, frequency sweep, amplitude sweep, time sweep and temperature sweep (gradient, step change or profile). Tests can be performed at constant stress or constant strain amplitude using Auto-stress mode.

With options

Almost all rheological measurements require accurate temperature measurement and control. The CVO accepts a variety of temperature control units, which are easily interchangeable, to cover all applications. By virtue of the mounting system used, space and access for sample loading and trimming are not compromised when changing the temperature control system. Available units include a range of fluids circulators, Peltierdevices (plate and cylinders), electrically heated plates and a forced gas oven with a liquid nitrogen cooling option. Bohlintemperature control units are fully controlled by the software and the instrument detects which type of units is installed considerably simplifying installation.

Overview

Torque range

0.5μNm to 100mNm

Torque resolution

1nNm

Position resolution

0.9μrad

Frequency range

10μHz to 100Hz

Controlled speed range (CR mode)

50mrad s^-1to 320rad s^-1

Measurable speed range (CS mode)

0.1μrad s^-1to 320rad s^-1

Normal force N1 measurement range*

0.001N to 20N

Temperature range (dependent on control used)

-150°C to 550°C*

-40°C to 450°C

Temperature controls

Fluids Circulator

-40°C to 250°C

ETO (Extended Temperature Option)

-15°C to 300°C

Melts Oven

ambientto 450°C

PeltierPlate

-30°C to 200°C

PeltierCylinder

-20°C to 180°C

Universal PeltierOption – Coaxial Cylinder or Cone/Plate Geometries

ETC (Extended Temperature Cell)

ambientto 550°C*

ETC with optional LTU (Low Temperature Unit)

-150°C to 550°C*

*available if NormalForce option is fitted

Nominal operating voltage

110 or 220V

Size (with Peltierplate)

52cm (H) x 29cm (W) x 34cm (D)

Weight (with Peltierplate)

27kg