Severe service applications involving acids, alkalies, and high temperatures and pressures are good candidates for gaskets from flexible graphite sheet. These types of applications are found in many industries, including chemical and petrochemical, pulp and paper, energy, mining and resources, and general manufacturing and processing.
Gaskets from Flexible Graphite Sheet: Properties
Gaskets from flexible graphite sheet possess excellent resistance to corrosion from acids and alkalies, as well as high temperatures and pressures. Flexible graphite sheet also has good resistance to abrasive media, such as slurries, and gaskets cut from the material also exhibit excellent thermal conductivity and conformability which produces a superior seal.
Flexible graphite sheet is manufactured from mineral graphite (expandable flake graphite) and contains a carbon content of between 95 percent and 99 percent. The amount of carbon present in the sheet is a key determinant of its flexibility: the higher the percentage of carbon present, the more flexible the sheet.
CRG Gaskets from Flexible Graphite Sheet
A flexible graphite sheet which Canada Rubber Group (CRG) often uses to produce gaskets for severe service applications is Teadit style 2660/1660. Gaskets from Teadit style 2660/1660 have pressure-temperature sealing characteristics and capabilities that are far superior to all asbestos reinforced and non-asbestos reinforced sheet products. These gaskets are resistant to chemical attack by virtually all organic and inorganic fluids, with the exception of concentrated, highly oxidizing acids. In short, they are an excellent choice for many severe service applications.
CRG gaskets made from Teadit style 2660/1660 have a maximum service temperature in air of 450°C, 650°C in steam, and 3000°C in reducing or inert media. These gaskets will service pressures up to 2030 psi (140 bar).
Because gaskets from Teadit style 2660/1660 flexible graphite sheet have excellent flexibility, they conform well to irregular flange sealing surfaces. This property greatly eases gasket installation and provides confidence that a fully functioning seal will be achieved even with coarse or irregular joint/flange surfaces. An additional benefit is that these gaskets will seal with low to moderate bolt loads and, because of the material’s low creep relaxation, the re-torquing of bolts is rarely needed.
Teadit style 2660/1660 flexible graphite sheet is made from exfoliated graphite flake which is compressed into foil by a carefully controlled calendering process. In this process, the expanded flake particles are mechanically locked together without the use of fibers, binders or other additives. Sheets of graphite foil are then adhesive bonded and laminated to produce the required material thickness.
In addition to gaskets made from Teadit style 2660/1660 sheet, CRG also offers two additional variants:
Gaskets with a tanged core, fabricated from Teadit style 2663/1663 flexible graphite sheet.
Gaskets with a Mylar film insert, fabricate from Teadit style 2664/1664 flexible graphite sheet.
For further information on the above two gasket styles, please refer to our previous blog on this subject.
Using the latest production technology, CRG can supply gaskets from flexible graphite sheet for almost any application. CRGI flexible graphite gaskets are available in a range of sizes and thicknesses, and each gasket is produced to customer specifications. If required, we can supply gaskets from flexible graphite sheet with or without pressure sensitive adhesive (PSA) backing.
To find out more about how we can meet your flexible graphite gasket needs, please contact our sales department directly at crg@canadarubbergroup.com.