In the color fastness to rubbing test, the commonly used machine is the crockmeter. A rub fastness tester is a device specifically designed to simulate the color migration or fading of textiles under rubbing conditions. It usually consists of the following main components:

1. Test stand: The test stand of the friction fastness tester is usually made of solid materials and can provide a smooth and stable surface. During the test, the textile sample comes into contact with the test bench.

2. Friction head: The friction head of the friction fastness tester is used to apply friction force to the textile sample. The friction head is a round or square metal or ceramic plate whose surface is usually smooth. It comes into contact with the sample via a friction arm fixed to the machine.

3. Friction arm: The friction arm is the part that supports the friction head and applies pressure. The friction arm of the rub tester can have adjustable weight and length to adapt to different types of testing requirements.

4. Counter or indicator: Rubbing testers are usually equipped with a counter or digital indicator to record or display the number of rubs in order to evaluate the degree of color migration or fading.

In the color fastness to rubbing test, the textile sample needs to be fixed on the test stand, and the friction head is placed on the sample to apply a quantitative friction force. A corresponding rubbing cycle is then performed, usually to provide a standardized number of rubbings, such as 10, 20, 50 or 100 times.

It is important to note that the use of the rubbing fastness tester and the testing method should follow international standards (such as ASTM or AATCC) to ensure the comparability and accuracy of the test results. In addition, maintenance and calibration of test equipment is also important to ensure that it works properly and provides reliable test results.

In summary, color fastness to rubbing tests are typically performed using a crock tester, which is designed to simulate the color migration or fading of textiles under rubbing conditions. The friction fastness tester consists of a test bench, a friction head, a friction arm and a counter, and must be used in compliance with international standards and equipment maintenance requirements.