Saline hardness gauge device

The hardness of polymers is resistance to penetration against hard objects. Hardness is a key parameter in the manufacture of engineering parts. There are many methods and scales for hardness, such as saline hardness and Rockwell. The most important and common methods of polymer hardness gauge is saline shore hardness gauge. In this paper, we test the hardness of saline shore polymers. First we describe the saline hardness testing equipment and device

Before start to talk in a relationship with hardness, passion, etc., it is necessary to know that for someone who is just beginning to test the hardness does and does not know that must of which method to use, you must first tab technically, references, standard product or a national study, you can also detect which method should be used not

 A conversion between the amount of hardness in scale and technique, passion, and Rockwell in the figure given below, which is, of course, the correct way to calculate the hardness in accordance to the standard procedures of each of the tests individually, and this conversion is not recommended



تبدیل سختی شور و راکول

Hardness assessment saline shore hardness

Saline hardness, also known as durometer hardness, is very common for polymers and is divided into two types of conventional A and D. For hard objects such as metals usually use Rockwell Hardness. For slightly softer objects such as plastics usually use saline hardness assessment Type D and for very soft objects such as tires or TPE use saline hardness assessment Type A

Saline hardness assessment is a standard method based on measurement of saline index penetration to the sample. Saline hardness number is without Unit and can vary between 0 and 100. The higher the number measured for the higher hardness means the harder the material is

The penetration value of the index depends on the hardness of the material the viscoelasticity of the material the shape and type of the index as well as the duration of the test InGaN

Conceptual similarities between Rockwell method and saline hardness method can be clearly observed

In the figure below, you can see the difference in the dimensions of the tip of the collapsing indicator on the hardness of Type A and Type D


خرید آزمون سختی شور shore پلیمر

Reference standard of saline hardness test

National standard 1993, ISO 868 and ASTM D2240

Shore saline hardness test method

Equipment required

The machine determines the hardness of the shore A and D or the hardness of the shore gauge the base holder equip and sample stopwatch weights suitable for Force exertion

Test: specimen thickness of the specimen in accordance with national standard and ISO shall be at least 4mm and in accordance with ASTM standard at least 6mm. The dimensions of the test should be such that it can be spaced at least 9 mm from its edges and evaluated the hardness of the saline. The test surface should be perfectly smooth so that in the area where the saline hardness index needle was placed at least 6 mm radius around it is flat

To measure the hardness of the test on the horizontal surface of the machine for this embedded. Place the hardness of the gauge in the vertical position so that it is at least 9 mm away from the edges of the test. Raise the pressure base quickly, but without the impact, so that the indicator (saline hardness needle) on the sample and apply sufficient pressure

After 15 seconds, read the hardness number of saline polymer. Depending on the technical or standard specifications of the product feature, you can also read the hardness number of the moment 1 second after the full contact and make the proper pressure

You should do 5 different measurements that distance them from at least 6 mm and report their averages

To establish sufficient pressure in conducting the test on the hardness test Type A applying 1 kg weight and on the hardness gauge Type D 5 kg weight is recommended

When the hardness gauge type A and when the hardness gauge type d use

Usually for Robers, too soft plastics and TPE .. The saline hardness gauge type A is used and for other plastics of saline hardness gauge Type D. Another solution is the use of technical specifications or the product feature standard which usually specifies the type of polymer hardness gauge as well

The other way is to first measure the hardness with the hardness gauge saline A, if the number obtained was above 90 it is better to use the hardness gauge Type D. And also if you first used the Type D hardness gauge and the readings number was less than 20 it is better to use the type a hardness gauge