One
of the most important steps in using a durometer (rubber hardness tester) is to select the optimum type.
There are various types of durometer available based on different standards applied to a wide variety of subjects to be measured.
Among them the most popular models for rubber materials are ISO
7619 & ASTM D 2240-specified Type A Durometer (ASKER Model A)
and JIS K 6301 (abolished)-specified Type A Durometer (ASKER Model
JA). Other typical models include ISO 7619 & ASTM D 2240-specified Type D Durometer (ASKER Model D) for hard rubber and plastics, and ASKER-C (ASKER Model C) for soft rubber or flexible cellular materials.
·
Cone
point type.
Model D has this type.
·
Measuring Objects:
Hard rubber and plastics.
·
Flat
point type.
Model A and JA have this type.
·
Measuring Objects:
General rubber.
·
Hemispherical
point featuring larger contact area.
ASKER C has this type.
·
Measuring Objects:
Soft rubber and sponge rubber.
Principal
Standards
JIS K 6253
JIS K 7215
ASTM D 2240
ISO 7619
ISO 868
Durometer Type A
Indentor
Design [mm]
Height
shape
2.50
35-Deg.
Truncated
Cone 0.79
Spring
Load [mN(g)]
0 Degree
100 Degree
550
(56)
8050
(821)
Size & Shape
of
the pressure foot [mm]
41×16
(Rectangular)
Outside
Dimensions [mm]
Width 61
Depth 25
Height 115
Weight [g]
230
Principal
Standards
JIS K 6301
(Old JIS Type A, abolished in 1998)
Indentor
Design [mm]
Height
shape
2.54
35-Deg.
Truncated
Cone 0.79
Spring
Load [mN(g)]
0 Degree
100 Degree
539
(55)
8379
(855)
Size & Shape
of
the pressure foot [mm]
41×16
(Rectangular)
Outside
Dimensions [mm]
Width 61
Depth 25
Height 115
Weight [g]
230
Principal
Standards
JIS K 7312
Type ASKER C
Indentor
Design [mm]
Height
shape
2.54
5.08
Diameter
Hemisphere
Spring
Load [mN(g)]
0 Degree
100 Degree
539
(55)
8379
(855)
Size & Shape
of
the pressure foot [mm]
41×16
(Rectangular)
Outside
Dimensions [mm]
Width 61
Depth 25
Height 115
Weight [g]
230
Principal
Standards
JIS K 6253
JIS K 7215
ASTM D 2240
ISO 7619
ISO 868
Durometer Type D