What is UNCD?

What are the advantages of UNCD Faces?

Why should I use UNCD Faces?

Why does UNCD improve mechanical seal performance?

How thick is the UNCD film on the seal face?

How flat is the UNCD coated seal face?

Is adhesion to UNCD coating a concern?

What counterface materials can be mated with UNCD?

Can a UNCD Face be mated with itself?

How much cooler is the sealing surface due to UNCD's low friction?

How smooth is the UNCD coating?

What tests have been conducted to prove UNCD performance?

How does the increased cost of a UNCD seal compare to increased performance?

How do you grow the UNCD film?

What materials can be coated with UNCD?

If I send you a part, will you coat it?

How can I order a UNCD Face for my mechanical seal or a UNCD Seal for trial evaluation?

Can UNCD facing be repaired or recoated?

What is the warranty provided with UNCD?

What is UNCD?
UNCD (a form of nanocrystalline diamond) captures many of the best properties of natural diamond in a scalable thin film technology enabling diamond to be integrated into a wide range of products including mechanical seal faces. UNCD encompasses a proprietary family of materials manufactured using patented chemical vapor deposition processes. UNCD coatings are not diamond-like carbon films, but phase-pure crystalline diamond materials. For more information about UNCD, please check www.thindiamond.com.

What are the advantages of UNCD Faces?
Advantages of UNCD Faces include lower wear, lower friction, chemical resistance, non-sticking, biocompatibility, and can be mated against both soft and hard face materials.

Why should I use UNCD Faces?
Some reasons are: improve seal reliability, minimize seal leakage, longer seal service life, lower maintenance and operational costs, reduced heat generation for handling temperature sensitive fluid, dry running capability and increased energy efficiency.

Why does UNCD improve mechanical seal performance?
Heat and wear are common reasons for mechanical seal failure. UNCD’s very fine grain size and hardness result in exceptionally low friction and outstanding wear resistance for improving mechanical seal performance.

How thick is the UNCD film on the seal face?
The UNCD film on the seal face is only several micrometers thick.

How flat is the UNCD coated seal face?
The flatness is retained from the pre-coated seal face.

Is adhesion of UNCD coating a concern?
No, UNCD has excellent adhesion to the silicon carbide substrate. We pretreat the silicon carbide surface to ensure strong adhesion. The adhesion of the UNCD to the SiC has been measured to be stronger than the intrinsic strength of the SiC.

What counterface materials can be mated with UNCD?
UNCD is so smooth that it can be mated for high seal performance with either soft (carbon) or hard (silicon carbide) faces. Commercial diamond faces of other manufacturers have much coarser larger grain size than UNCD which require a diamond mating face to prevent the counterface from getting chewed up.

Can a UNCD face be mated with itself?
Our focus thus far has involved mating UNCD against conventional seal face materials. Using just one diamond face, instead of both faces diamond, helps lower the cost for the mechanical seal.

How much cooler is the sealing surface due to UNCD's low friction?
The degree of cooling depends on the application. However, with UNCD faces, less heat will be generated that needs to be flushed from the seal.

How smooth is the UNCD coating?
Coating roughness depends on several factors, including the roughness of the substrate and thickness of the coating layer. UNCD coating is smooth as deposited with a typical surface roughness of about 30 nm RMS (approx. 1 microinch).

What tests have been conducted to prove UNCD performance?
Extensive validation tests of UNCD including wear and friction have been conducted over the past several years by us, Argonne National Laboratory, and seal manufacturers.

How does the increased cost of a UNCD seal compare to increased performance?
Every application seems unique. Customers should consider the total cost of ownership of the seal rather than just the purchase price. UNCD can be a great bargain when factoring such benefits as a more reliable seal, and lower maintenance and operational costs. Downtime for many process applications can be very expensive.

How do you grow the UNCD film?
The UNCD film coating is applied to the carbide substrate using a chemical vapor deposition (CVD) method. This method results in converting carbon from a gas to a solid diamond structure using elevated temperatures.

What materials can be coated with UNCD?
We can deposit thin films of UNCD on a variety of substrate materials. Our standard substrate material for UNCD seal faces is alpha self-sintered silicon carbide which is sourced from a variety of leading manufacturers. Chances are good that we can accommodate your chosen grade and brand of silicon carbide. In addition, materials that form carbides tend to also make good substrates. Please contact us to inquire about additional materials.

If I send you a part, will you coat it?
We are not a coating company. We would be happy to supply you seal seats per your engineering drawing with UNCD. If you require a specific source of silicon carbide, please contact us.

How can I order a UNCD Face for my mechanical seal or a UNCD Seal for trial evaluation?
Please see Doing Business with Us.

Can UNCD facing be repaired or recoated?
Due to the extreme hardness and chemical inertness of UNCD, it is typically impractical to repair. In most cases it is more cost effective to replace than to repair or recoat.

What is the warranty provided with UNCD?
Our warranty is defined in our standard terms and conditions of sale shown at our website.