Checkline Durometer Technical Information

Description
Call for Price
Rubber & Plastic Hardness Tester
Unique flexible coupling system automatically aligns the presser foot to the surface of sample

The principle used to measure hardness is based on measuring the resistance force of the penetration of a pin into the test material under a known spring load. The amount of penetration (max. 2.5 mm) is converted to hardness reading on a scale with 100 units.

1. Whenever possible, a Durometer measurement should be taken at least 12 mm (approx. 0.500") in from the edge of a sample, as the hardness characteristic of any sample tends to change at at the edges.

2. Whenever possible, the thickness of a sample should exceed 6 mm (approx. 0.250"). If the sample is thinner then this, then the sample can be backed with a sample of the same material to increase the thickness.

3. Test Coupons or test blocks (rubber or plastic) should not be used for calibration verification. As all samples are subject to characteristic changes over time along with temperature and lighting conditions, the rated Shore value when supplied as new can and will vary with age. Proper calibration verification requires independent confirmation of the internal spring forces along with the verification of the pin displacement vs. the indicated value on the scale.

4. Per the ASTM Standard D 2240, readings below 10 and above 90 are not to be considered reliable and should be discarded. Therefore, it is important to select the approapriate Scale that will provide results between 10-90 units.

ASTM D-2240

line
Reference Guide & Scale Comparison
line

TypeApplicationIndentorSpring Force
ASoft rubber, plastics and elastomers.Flat cone point, 35°822 g
1.81 lb
BHarder elastomers and plastics. Paper and fibrous materials, Use above 93 A scale.Sharp cone point, 30°822 g
1.81 lb
CMedium hard elastomers and plastics. Also useful to avoid surface marks.Flat cone point, 35°4536 g
10.0 lb
DHard rubber and plastics such as thermo plastics, flooring and bowling balls.Sharp cone point, 30°4536 g
10.0 lb
DODense granular material and textile windings.3/32" Spherical4536 g
10.0 lb
OVery soft elastomers, textile windings and soft granular materials. Use below 20 A scale.3/32" Spherical822 g
1.81 lb
OOLight foams, sponge rubber gels and animal tissue.3/32" Spherical113 g
0.25 lb
OOOUltra soft gels and sponge rubber.1/2" Spherical113 g
0.25 lb
MMaterials as thin as .050"Sharp cone point, 30°-


line
Type | Comparision Table
line

This chart is for comparison purposes only. It cannot be used for conversion reference.

Durometer Spring Force Calibration - All Values in Newtons (N)
Indicated ValueType MType A, B, OType C, D, DOType OO
00.3240.550.203
100.3681.34.4450.294
200.4122.058.890.385
300.4562.813.3350.476
400.53.5517.780.666
500.5444.322.2250.667
600.5895.0526.670.748
700.6335.831.1150.839
800.6776.5535.560.93
900.7217.340.0051.02
1000.7658.0544.451.111
N/durometer unit0.00440.0750.44450.00908
Cal Tolerance±0.0176 N±0.075 N±0.4445 N±0.0182 N

Operating Stand

Durometer Type

OS-2

A, B, E and O

OS-2H (Air Dampened)

A, B, E and O

OS-3 (Air Dampened)

M

OS-4

OO, OOO and OOO-S

OS-4H (Air Dampened)

OO, OOO, OOO-S and M

OS-1

A, B, C, D, E, DO, O, OO, OOO
and OOO-S


line
Call for Price
line

Check the items you would like to purchase then click "Add To Cart"
ItemPrice