M19-354
Page 7
©
2019 AMETEK Brookfield Inc. All rights reserved.
I.3 Details on Viscosity Measurement Range and Accuracy
Per DIN 53015, the Falling Ball method is suitable for measuring dynamic viscosities ranging
from 0.6 mPa•s to 250,000 mPa•s at temperatures from -5ºC to 150ºC. Use is made of six
balls having different diameters, each ball covering part of the range. All guideline values and
referenced parameters in the following table are per DIN 53015.
Ball
No.
Viscosity
measurement
range (guideline
values) (mPa•s)
Material
Density
(guideline
value)
(g/cm
3)
Ball
diameter
(mm)
Deviation
from
circularity
(mm)
Calibration
constant
(guideline
value)
(mPa•s•cm
3
/g•s)
1
0.5 to 10
Borosilicate glass
2.4
15.81 ± .01 ± 0.0005
0.007
2
9 to 140
Borosilicate glass
2.4
15.6 ± 0.05 ± 0.0005
0.09
3
40 to 700
Ni/iron
8.1
15.6 ± 0.05 ± 0.001
0.09
4
150 to 5,000
Ni/iron
8.1
15.2 ± 0.1
± 0.001
0.7
5
1,500 to 50,000
Ni/iron
8.1
14.0 ± 0.5 ± 0.001
7
6
Above 7,500
Ni/iron
8.1
11.0 ± 1
± 0.002
35
These are the accuracy values reported in the DIN53015 standard.
AMETEK Brookfield has determined the accuracy of the viscometer using balls 2 and 3 according
to the method specified in the DIN53015 standard.
To determine the accuracy of the viscometer for balls 1, 4, 5 and 6, please refer to the method
specified in the DIN 53015 standard.
I.4 Description of the Equipment
Refer to Figures 1 and 2. Specific items identified on the Falling Ball Viscometer are identified by
parentheses ( ) in the following steps:
1. The Falling Ball Viscometer must be level. The level is adjusted using the three Leveling
Feet (4) on the base. Adjust so that the bubble level on top of the Falling Ball Viscometer
is centered within the circle. Check level periodically during use.
2. The working angles of the KF40 are 80°, 70°, 60° and 50° relative to horizontal. The DIN
53015 working position of 80° is the preferred position. The different working angles are
secured by the adjustment screw (5). To select a working angle, the adjustment screw (5)
should be loosened by turning it counter-clockwise approximately one rotation. After the
working angle is selected, the adjustment screw should then be tightened again.
3. The two running directions of the balls can be chosen by swiveling the viscometer, which
is kept in place by the Stop to hold the viscometer in position (22).
4. The glass tube (6) is surrounded by a waterbath jacket (9) which is fixed between the upper
plate (7) and lower plate (8). The upper locking plug (16) with lid (20), the lower locking
