ASTM D5230 Standard Test Method for Carbon Black - Automatic Individual Pellet Hardness

The ASTM D5230 test covers a procedure for measuring individual pellet hardness of carbon black with an automatic pellet hardness tester. Individual pellet hardness is related to several carbon black properties. These include mass strength and wear. The subsequent level of dispersion obtained in some mixed compounds containing carbon black may be affected by pellet hardness.

A sample of carbon black is passed through two sieves to isolate a fraction of uniform size. From this part, the most spherical pellets are selected and placed in the test device. Individual pellets are pressed against a plate with a load cell to measure force. When pressure is applied, the pellet will either break with a rapid decrease in force or the pellet will simply break.

Individual pellet hardness is the maximum force before a force reduction of at least 3 cN, or the maximum force required to compress the pellet to 90%, whichever comes first. Acceptable pellet hardness should be accepted by the user and manufacturer.

Automatic Pellet Hardness Tester, absolute measurement accuracy of 62 cN (2 gf) for force measurement and 60,1 mm for diameter measurement and 60,5 cN (0,5 gf) relative accuracy for force measurement and 0,02 mm diameter measurement for and consists of the following main components and features.

A means must be obtained to automatically load the pellet onto the shipping plate so that it contacts the second plate with minimal force. Typically, a roller includes a force measuring device. A tool is used to carry the required force 2 cN (2 gf) to detect the contact, the vehicle to apply the force at a constant rate, and the pellet to minimize its movement during the application of force.

A control device is used to guide the instrument through the test cycle, which includes crushing the pellet under controlled conditions, measuring and storing the results of initial diameter and crush force determinations, cleaning the parts from the plate surfaces, and starting the next process.

An algorithm is devised to determine the individual test endpoint (determination) as the maximum force observed before a certain reduction in diameter or a certain decrease in strength from the maximum observed force first occurs.

Values ​​stated in SI units should be accepted as standard. Values ​​in parentheses are for informational purposes only.

This standard does not purport to address all, if any, safety concerns associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health and environmental practices and to determine the applicability of regulatory restrictions prior to use.

Our organization also provides testing services within the framework of laboratory testing services, within the scope of ASTM D5230 Standard Test Method for Carbon Black - Automatic Individual Pellet Hardness.