The name may be unfamiliar but Vellumoid is one of the oldest gasket materials. Age hasn’t rendered it obsolete though and there are still applications where it may be a good choice. In this blog post we’ll explain what Vellumoid Gasket Material is and where you might want to use it.
A Mix of Paper, Glue and Sugar
Vellumoid is cellulose fiber impregnated with a protein glue and gylcerin. It was developed back in the 1890s. Apparently seeking to develop a waterproof paper, the inventor created something that looked and felt like vellum, (a high-quality form of parchment.) And from those humble origins, they named it “Vellumoid”.
Today the Vellumoid company, based in Worcester, MA, has grown an entire family of materials from this simple beginning. The original material is sold as “Branded Vellumoid” while variants are impregnated with other materials that perform well in gasket applications.
Properties and Performance of Vellumoid
The original Vellumoid is very water-resistant, which was the original goal, and also holds up well against antifreeze, water-based cutting fluids, gasoline and lubricating oils. It’s also mold-resistant, (by virtue of the glycerin,) so is often a good choice in damp locations.
Compressibility is excellent, which is one of the traits that make it interesting for gasket use. However, tensile strength is low and the upper-temperature limit is 250⁰ F (121⁰ C).
Other variants of Vellumiod incorporate materials that improve properties. Velbuna WG-5 for example is impregnated with nitrile and withstands up to 300⁰ F (149⁰ C) and Vellutherm 600 goes up to 350⁰ F (177⁰ C).
When to Use Vellumoid
Excellent compressibility makes it good for sealing uneven flange surfaces. That’s something you might encounter when rebuilding or restoring vintage machinery, and where Vellumoid might help add authenticity. Of course, it will work just as well in modern piping systems carrying hot or cold water or similar fluids.