How to choose the Best Coating System

For selecting the most appropriate coating system, different criteria should be taken into consideration, such as:

• Maintenance type and strategy (predictive or corrective)
• Wear resistance and thickness of coatings
• Mechanical properties of coatings (pressure, impact, temperature)
• Corrosion resistance of coatings
• Surface position during the coating procedure
• Amount of heat input during coating
• Necessity for preheating or postheating
• Repairability of coatings

Price/efficiency ratio, economic priorities and specific needs are other important criteria for decision making.
Furthermore, for repair coating it is of interest to know if dismantling is necessary or if in situ repair is possible.

Coating selection:

Procedure for coating selection

Wear mechanisms

• Friction / adhesion
• Abrasion

Abrasion

• Erosion

Erosion: Heavily worn Pelton wheel

• Cavitation

Cavitation: Agitator propeller

• Surface fatigue

Surface Fatigue: Tread of wheel (railway)

• Combined wear

Combined wear: Hot working die

Systematic wear analysis

• Design properties
• Base body (initial stage)
• Opposing body / Intermediate body
• History
• Base body (final stage)
• Special parameter / properties

Corrosion mechanisms

Different types of corrosion

• Wet corrosion - without mechanical stress

Uniform corrosion

Crevice corrosion

Pitting corrosion

• Wet corrosion - with mechanical stress

Stress corrosion,
Microsection

• Chemical

High temperature corrosion
combined with erosion,
Stainless steel,
Drying plant - Cement work

Hardness test

The hardness tester forces a small sphere (Brinell, HB), a diamond pyramid (Vickers, HV) or a cone (Rockwell C, HRC) into the surface of a metallic material.

Hardness tests

Thermal conductivity

Thermal conductivity

For further information, on-site training, technical advise or project management, please do not hesitate to contact us.