DiamondFaces® mechanical seals from EagleBurgmann deliver exceptional performance

Burgmann Industries GmbH & Co. KG, Wolfratshausen/ Germany has introduced a revolutionary new diamond coating for mechanical seals, which offers excellent protection against wear during dry running, in applications with mixed friction and under exposure to abrasive media.

The specially developed crystalline diamond coating offers the same advantages as natural diamond and is suitable for applications in the oil and gas industries (e.g. multi-phase pumps), slurry applications, the chemical and pharmaceutical industries, and domestic applications (hot water). The diamond coating on the seal face has a thickness of up to 8 µm. It is extremely hard, exceptionally long wearing and features outstanding heat conductivity, excellent chemical resistance and low friction, with optimal adhesion to the substrate being a decisive feature in this respect.

EagleBurgmann’s DiamondFaces® is a microcrystalline coating which is applied to the seal face using a chemical vapor deposition (CVD) process. The fundamental difference is the horizontal arrangement of the tungsten wires (which reach temperatures of 2,000°C) in the vacuum oven; coatings up to 8 µm thick can thus be applied without affecting the flatness of the sealing faces, and this is vital for proper functioning of the mechanical seal. The crystalline diamond forms a chemical bond with the silicon carbide facing, and as a result the adhesion of the coating exceeds all known practical application requirements.

Successful field application
In addition to field trials, some of the seals are already being used in tough continuous operation, for example in a Bornemann multiphase pump (see photo) which is used to transport extremely abrasive media. The pump is being used for cost-effective production in Canada’s large oil sand fields. Using the new SAGD process (Steam Assisted Gravity Drainage), steam is injected into the well to recover the crude oil or bitumen, and the pump has to handle a mixture of gas and solids. The single mechanical seal which had been used previously failed repeatedly after a short period of time. Now the same seal with a diamond coating delivers vastly improved performance and has been running without problem for 4 months.

Brief summary
Technical advantages
- hard/hard pairing virtually eliminates wear and significantly reduces leakage
- universal chemical resistance facilitates standardization
- minimal friction reduces cooling requirements
- low operating temperature increases service life of the system
- and especially the life of the O-rings
- suitable for higher operating limits

Key features
- maximum process reliability
- running performance improved many times over
- unparalleled wear protection
- minimal friction coefficient and heat generation even in the case of
- insufficient lubrication and dry running
- extreme reduction in MTBF/MTBR intervals and associated costs

www.eagleburgmann.com