Tribological Properties

Diamond excels in a low coefficient of friction and extremely low wear, even under dry running conditions.

Heger Diamond offers the full potential of diamond as CVD coating onto your mechanical seals and bearings.

The main focus is the coating of mechanical seals  made of silicon carbide

Crystalline diamond is often confused with Diamond Like Carbon (DLC), however the physical properties are completely different. DLC has a hardness of 3500 HV our coating (real diamond) has 10000 HV. Furthermore the adhesion of DLC is weaker because of the lower coating temperature (250°C) which prevents a strong bond.

Diamond is deposited at temperatures of 800°C which results in a strong chemical bonding that is needed for high tribological loads.

The most extreme operating conditions for mechanical seals are dry running. If a conventional uncoated mechanical seal is used, the wear and friction increases very fast, the seal gets hot and the faces as well as the secondary sealing elements are destroyed. This results in leakage and in worst case in a complete breakdown of the sealing system.

The Diamond Layer

 

If a diamond coated mechanical seal is used in same conditions the friction stays on a low level with almost no wear. With such diamond coated seals mixed lubrication and high abrasion by debris is possible. Because these advantages are achieved by  a very thin coating only neither  the  design nor the concept have to be changed.

 Abrasion

Besides the wear by tribological load it is the wear caused by abrasion that causes a lot of problems. Every application handling slurries;  mixing, pumping, conveying has to deal with this problem. Even in a lubricated tribosystem a third party i.e. sand or similar, can cause fatal damage to the sliding surfaces. Long time stability and almost no loss of surface material are the demands that are made.

 Heger Crystalline Diamond :

  • the hardest known material

  • highly abrasion resistant

  • chemically inert in almost all environments

 

 

Diamond Coating for Nozzles