LABOMAR TEKNOLOJİK ÇÖZÜMLER

Tel : 0216 417 70 01 / Fax : 0216 417 33 50

 
 

www.labomar.net   /  webinfo@labomar.net  

 

 

 

Wells-Brookfield Cone/Plate

Rapid Determination Of Absolute Viscosity


Introduction
The Wells-Brookfield Cone/Plate Viscometer gives researchers a sophisticated instrument for routinely determining absolute viscosity of fluids in small sample volumes. Its cone and plate geometry provides the precision necessary for development of complete rheological data.

Principle of Operation
The Wells-Brookfield Cone/Plate Viscometer is a precise torque meter which is driven at discrete rotational speeds. The torque measuring system, which consists of a calibrated beryllium-copper spring connecting the drive mechanism to a rotating cone, senses the resistance to rotation caused by the presence of sample fluid between the cone and a stationary flat plate.

The resistance to the rotation of the cone produces a torque that is proportional to the shear stress in the fluid. The amount of torque is indicated either on a dial or digital display, depending on model. This reading is easily converted to absolute centipoise units (mPa·s) from pre-calculated range charts. Alternatively, viscosity can be calculated from the known geometric constants of the cone, the rate of rotation, and the stress related torque. 

The correct relative position of cone and plate is obtained by following a simple mechanical procedure without the need for external gauges or supplementary instrumentation.

The stationary plate forms the bottom of a sample cup which can be removed, filled with .5 ml to 2.0 ml of sample fluid (depending on cone in use), and remounted without disturbing the calibration. The sample cup is jacketed and has tube fittings for connection to a constant temperature circulating bath.

The system is accurate to within ±1.0% of the working range. Reproducibility is to within ±0.2%. Working temperature range is from 0oC to 100oC.

Various cone spindles are available for use with the Wells-Brookfield Cone/Plate instruments. One cone spindle is provided with the instrument and is calibrated for use with the sample cup. Additional cone spindles may be purchased and will be calibrated for use with the same sample cup.

Versatility of Application

  • The Wells-Brookfield Cone/Plate Viscometer provides a wide variety of shear rates and viscosity ranges, which can be further extended by the use of interchangeable cone spindles. Different models can be selected to meet the specific range of viscosities and shear rates required. Shear rates as high as 1875 sec-1 (DV-III Rheometer) can be achieved.

  • The small sample volume required permits rheological evaluations to be made on materials where sample availability is limited, such as biological fluids and thick film coatings that contain precious metals.

  • All wetted parts are stainless steel for corrosion resistance and ease of cleaning.

  • Optional purge fitting, luer fitting, and embedded temperature probe available.

Electronic Gap Setting
Wells-Brookfield Cone/Plate Digital Viscometers/Rheometers are now supplied with an advanced "Electronic Gap Setting" feature. This technology allows faster set-up time and minimizes the possibility of "gap" adjustment errors. With the enhanced system, a bright LED lights up when a "hit point" is achieved. A simple turn of the micrometer adjustment ring and the "gap" is set, reducing the time required associated with manual detection methods.
The new electronic gap setting system is now a standard feature on our complete line of Wells-Brookfield Cone/Plate Digital Viscometers/Rheometers. These instruments provide precise shear profiles necessary to determine viscosity and develop rheological data.

LV SERIES VISCOMETERS & RHEOMETERS
Cone Spindle*
LVT
LVDV-I+
LVDV-II+*
LVDV-III
Shear Rate** (sec-1)
Sample Volume (mL)
CPE-40
CPE-41
CPE-42
CPE-51
CPE-52
CP-40
CP-41
CP-42
CP-51
CP-52
0.5-1,023
1.9-3,837
1.0-2,000
8.0-16,000
15.4-30,720
0.3-1,023
1.2-3,837
0.6-2,000
4.9-16,000
9.3-30,720
0.2-3,070
0.6-11,150
0.3-6,000
2.4-48,000
4.6-92,160
0.1-3,070
0.5-11,150
0.2-6,000
1.9-48,000
3.7-92,160
7.50N
2.00N
3.84N
3.84N
2.00
0.5
2.0
1.0
0.5
0.5

RV SERIES VISCOMETERS & RHEOMETERS
Cone Spindle*
RVT
RVDV-I+
RVDV-II+**
RVDV-III
Shear Rate*** (sec-1
Sample Volume (ml)
CPE-40
CPE-41
CPE-42
CPE-51
CPE-52
CP-40
CP-41
CP-42
CP-51
CP-52
3.3-6,450
12.3-24,560
6.4-12,800
51.2-102,400
98.3-30,720
3.3-10,900
12.3-40,933
6.4-21,300
51.2-170,666
98.3-327,666
1.6-32,700
6.1-122,800
3.2-64,000
25.6-512,000
49.2-983,000
1.3-32,7000
4.9-122,800
2.6-64,000
20.5-512,000
39.3-983,000
7.50N
2.00N
3.84N
3.84N
2.00
0.5
2.0
1.0
0.5
0.5

HA SERIES VISCOMETERS & RHEOMETERS
Cone Spindle*
HAT
HADV-I+
HADV-II+**
HADV-III
Shear Rate***(sec-1)
Sample Volume (nl)
CPE-40
CPE-41
CPE-42
CPE-51
CPE-52
CP-40
CP-41
CP-42
CP-51
CP-52
6.6-13,080
24.6-49,120
12.8-25,600
102.4-204,800
196.6-393,200
6.6-21,800
24.6-81,866
12.8-42,600
102.4-341,333
196.6-655,333
3.3-65,400
12.3-245,600
6.4-128,000
51.2-1,024,000
98.3-1,966,000
2.6-65,400
9.8-245,600
5.1-128,000
41.0-1,024,000
78.6-1,966,000
7.50N
2.00N
3.84N
3.84N
2.00
0.5
2.0
1.0
0.5
0.5

HB SERIES VISCOMETERS & RHEOMETERS
Cone Spindle*
HBT
HBDV-I+
HBDV-II+**
HBDV-III
Shear Rate*** (sec-1
Sample Volume (ml)
CPE-40
CPE-41
CPE-42
CPE-51
CPE-52
CP-40
CP-41
CP-42
CP-51
CP-52
26.2-52,400B 98.3-196,600
51.2-102,400
409.6-819,200
786.4-1,572,860
26.2-87,200
98.3-327,466
51.2-170,666
409.6-1,365,333
786.4-2,621,333
13.1-261,600
49.1-982,400
25.6-512,000
204.8-4,096,000B 393.2-7,864,000
10.5-261,600
39.3-982,400
20.5-512,000
163.8-4,096,000
314.6-7,864,000
7.50N
2.00N
3.84N
3.84N
2.00
0.5
2.0
1.0
0.5
0.5

*CPE refers to electronic gap adjustment, while CP-refers to manuel gap adjustment.
**Maximum viscosity range shown is at 0.1 rpm.
***N=RPM Example: RV Viscometer with CPE-42 spindle at 10 RPM has shear rate 3.84 x 10 = 38.4 sec-1.

CONE SPINDLE DIMENSIONS
CONE SPINDLE
ANGLE (deg.)
RADIUS (cm)
CP-40 or CPE-40
0.8
2.4
CP-41 or CPE-41
3.0
2.4
CP-42 or CPE-42
1.565
2.4
CP-51 or CPE-51
1.565
1.2
CP-52 or CPE-52
3.0
1.2