What is expanded graphite gasket?

Materials from expanded graphite are used for demanding sealing at high temperatures, especially in chemical and petrochemical industry. Products are made of very pure expanded graphite and may be reinforced with various metal inserts (metal foils).

What is flexible graphite?

Flexible graphite – also known as expanded graphite or exfoliated graphite – is produced from purified natural graphite flakes. In the manufacturing process the flakes are mixed with a highly oxidizing acid to produce graphite intercalation compounds. These are expanded by a sudden application of high temperature.

Is graphite flexible or brittle?

Graphite is naturally a very brittle compound and cannot be used as a structural material on its own due to its sheer planes (although it is often used to reinforce steel).

What are graphite sheets?

Natural graphite sheet (NGS) is a compressible, porous, electrically and thermally conductive material that has been used primarily to make sealing gaskets because of its ability to conform to rough surfaces, withstand high temperatures, and resist corrosive fluids.

Where are graphite gaskets used?

Graphite is generally used in high temperature and high pressure environments and commonly finds applications in steam cycling or exhaust applications. These gaskets provide a higher performance seal in these conditions than non-asbestos jointing.

What is graphite gasket made of?

Flexible graphite gaskets reinforced with a 316 stainless steel foil (0.002” thick) made from material typically 98% graphite. Leachable chloride typically less than 50 ppm. Sulfur content: 1200 ppm. Compressibility: 35%.

How do you expand graphite?

The method for making graphite is expandable [34,53]: First, they mix natural graphite into nitric acid and sulfuric acid. After 24 h, the reaction between the graphite plates and the acid passes through; then the mixture is filtered, washed with water, and dried in the oven at low temperature.

What is the difference between grafoil and graphite?

Flexible graphite is a generic commercial term. The name Grafoil® is the original brand name of flexible graphite owned by GrafTech, a company founded in 1886. Grafoil® material was first introduced by Union Carbide in the 1960s. Flexible graphite is 95% – 99% carbon.

What are the five uses of graphite?

Let’s look at some common uses of graphite below.

• Writing Materials.
• Lubricants.
• Refractory.
• Nuclear Reactors.
• Batteries.
• Graphene Sheets.

Does graphite absorb water?

It is well known that graphite can absorb large quantities of water, which can represent an abundant source of oxygen impurities in fusion plasmas if the corresponding components are not properly outgassed.

What is graphite foil used for?

Graphite Foil is an excellent graphite gasket sheet material, used in the automotive, petroleum and chemical, paper, and nuclear industries. Acts as a thermal barrier at high temperatures to provide outstanding reflectivity. Graphite Foil is used to make bipolar graphite plates in the fuel cell industry.

What are graphite sheets made of?

What is Graphite Sheet? Graphite Pads & Sheets are composed of graphite, the isotope of pure carbon that arranges itself in stacked sheets. Graphite’s sheet-like crystals, graphene, offers superior in-plane thermal conductivity compared to its through-plane thermal conductivity.

Are graphite gaskets good?

Graphite Gaskets They have excellent compressibility, can withstand high temperatures, and won’t creep, cold-flow, or become brittle. Graphite coatings allow for gasket movement without damage.

What are graphite washers used for?

Washers can be produced to the tolerances and shape that you require. Graphite is typically used in high temperature applications, such as in the prescence of steam.

Why graphite is used in gasket?

Graphite is known to excel in extreme conditions, withstanding heat, pressure and aggresive chemicals. It is especially noted for dimensional stability in high temperatures and pressure fluctuations. Because of these features, graphite gaskets and seals are often called to use in: Refineries.

What is expandable graphite used for?

expandable graphite as flame retardant. One of the principal applications of expandable graphite is as a flame retardant. As a result of the heat of a fire the graphite expands and creates an intumescent layer on the surface of the material.

Does graphite expand?

Graphite is also unique due to its thermal expansion properties (CTE). Typically, when a material or substance is heated, it expands. However, graphite has a remarkably low coefficient of thermal expansion; which means that it can be heated and be exposed to extremely high temperatures without expanding all that much.

Which is better graphite or PTFE?

Graphite packings can be treated with PTFE to get better benefits such as preventing colour contamination, gaining better stability etc. Both graphite, as well as PTFE packings, are cost-effective as they bothare durable and require low maintenance.

Is grafoil non-asbestos?

It is an ideal facing material for flat gaskets It contains no binders or resins. No binders or resins. Non-fibrous. Non-asbestos.

What is another name of graphite?

Graphite Synonyms – WordHippo Thesaurus….What is another word for graphite?

carbon	charcoal
culm	anthracite