Information on the most widely used ASTM standards within the materials testing industry
Model: UT2051, ISO 868, ISO 7619
Shore Hardness tester / durometer (rubber durometer) is widely used for measuring the hardness of rubber and plastics. It features a simple structure, ease of use, compact size, light weight, and intuitive reading. It can be carried for handheld measurement or installed on a matching production fixed-load stand of the same model for fixed-load testing. The product is manufactured with reference to ISO 868 and ISO 7619.
General Introduction
Shore Hardness tester / durometer (rubber durometer) is widely used for measuring the hardness of rubber and plastics. It features a simple structure, ease of use, compact size, light weight, and intuitive reading. It can be carried for handheld measurement or installed on a matching production fixed-load stand of the same model for fixed-load testing.
Product Standards and Scope of Use:
1. The product is manufactured with reference to ISO 868 and ISO 7619 international standards and complies with GB/T531, JB6148, and JJG304 standards.
2. Shore A hardness tester is widely used for hardness testing of medium and low hardness plastics, various rubbers, polyesters, leather, wax, and other materials.
3. Shore C hardness tester is suitable for testing the hardness of microcellular plastic materials containing foaming agents, with a compression stress of 0.5 kg/cm² or more at 50% compression. It can also be used for hardness testing of other materials with similar hardness.
4. Shore D hardness tester for hardness testing of high-hardness materials such as hard rubber, hard resin, acrylic, organic glass, thermoplastic plastics, printed circuit boards, fibers, etc.

Shore Hardness Reference Blocks
Key Features
A steel indenter of a certain shape is pressed vertically into the surface of the specimen under the action of a test force. When the surface of the indenter is completely in contact with the specimen surface, the tip of the indenter protrudes a certain length L relative to the indenter base plane. The value of L is used to characterize the Shore hardness. The larger the L value, the lower the Shore hardness; conversely, the smaller the L value, the higher the Shore hardness. The calculation formulas are:
HA = 100 - L/0.025
HD = 100 - L/0.025
HC = 100 - L/0.025
Where HA is the Shore A hardness. As shown by the formulas, Shore A hardness is related to the indenter displacement. By measuring the indenter displacement, the Shore A hardness value can be calculated.
Shore hardness testers are mainly divided into three types: A, C, and D.
Their measurement principles are exactly the same, with the only difference being the size of the indenter. The A-type has a tip diameter of 0.79 mm; the Shore A hardness tester is used to measure soft plastics, rubber, synthetic rubber, felt, and leather. The D-type has a tip diameter of 0.2 mm, i.e., a radius of R0.1. The Shore D hardness tester is used to measure the hardness of hard plastics and hard rubber, such as flooring materials, bowling balls, and other on-site hardness measurements. The C-type indenter is a spherical tip with a diameter of 5 mm. The Shore C hardness tester is used to measure soft materials like foam and sponge.
ISO 868
ISO 7619
GB/T531,
JB6148, and JJG304
Main Technical Specification
| Model | UT2051A | UT2051C | UT2051D |
| Measuring range | 0-100HA | 0-100HC | 0-100HD |
| Tolerance | Within 10-90 degrees, the error is less than ±1 degree. | ||
| Resolution | 1 degree | ||
| Press needle stroke | 2.5mm | ||
| Press needle pressure | 0.55N-8.05N | 0.55N-8.05N | 0-44.5N |
| Press needle head size | Ф 0.79 mm | SR2.5mm | SR0.1MM |
| Size | 115×60×25mm | ||
| Weight | 160g | ||
| Optional part | Test stand bracket. | ||
| Model | UT2051SA | UT2051SC | UT2051SD |
| Measuring range | 0-100HA | 0-100HC | 0-100HD |
| Tolerance | Within 10-90 degrees, the error is less than ±1 degree. | ||
| Resolution | 1 degree | ||
| Press needle stroke | 2.5mm | ||
| Press needle pressure | 0.55N-8.05N | 0.55N-8.05N | 0-44.5N |
| Press needle head size | Ф 0.79 mm | SR2.5mm | SR0.1MM |
| Size | 115×60×25mm | ||
| Weight | 160g | ||
| Optional part | Test stand bracket. | ||
Shore Hardness Tester Stand
The hardness tester stand is a new generation of Shore hardness tester stands developed by our company. It uses high-quality black marble as the base and high-strength delicate tempered glass as the testing platform, greatly improving testing stability and making measurement results more accurate. The stand has a reasonable structure and an attractive appearance.
AC model is compatible with A and C type Shore hardness testers, D model is compatible with D type hardness testers.
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| Shore A C hardness tester stand | Shore D hardness tester stand |
Shore A C D Hardness Tester Comparison Table
| Shore Hardness D | Shore Hardness C | Shore Hardness A | Types of Polymers |
| 90 | Hard plastic | ||
| 86 | |||
| 83 | |||
| 80 | Medium hardness plastic | ||
| 77 | |||
| 74 | |||
| 70 | |||
| 65 | 95 | ||
| 60 | 93 | 98 | |
| 55 | 89 | 96 | Soft plastic |
| 50 | 80 | 94 | |
| 42 | 70 | 90 | |
| 38 | 65 | 86 | |
| 35 | 57 | 85 | |
| 30 | 50 | 80 | |
| 25 | 43 | 75 | |
| 20 | 36 | 70 | |
| 15 | 27 | 60 | Rubber |
| 12 | 21 | 50 | |
| 10 | 18 | 40 | |
| 8 | 15 | 30 | |
| 6.5 | 11 | 20 | |
| 4 | 8 | 10 |
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