1. Scale: The main component carbonate (softer) sulfate (harder) silicate (harder).

2. Coal tar scale: The main components of carbon-containing organic compounds and some organic and inorganic mixture.

3. Rust Scale: The main component of the metal deposits.

4. Dirt: The main component of nature in a variety of impurities particles, grease and other liquid formed long-term accumulation of liquid beads.

5 material scale: the main component of the working medium in the equipment is due to changes in working conditions and other causes of the working medium on the device deposition, so the dirt is a component. The most complex structure of the scale, the most difficult to clean For example, alumina trough

The "pot Pakistan."

6. Mixing scale: in a device at the same time knot above the mixture of two or more dirt. Liquid, more complex scale.

7. Grease: The main ingredient is oil.

Glue scale: The main ingredient is plastic material.