Choosing the Right PTFE Filler for Your Applications

October 10, 2019 by  
Filed under Uncategorized

PTFE, or polytetrafluoroethylene, tubing is used in various industrial applications. Sometimes, PTFE tubing manufacturers can add fillers that enhance certain properties. The type of filler you need depends on how you will apply the tubing. Here are some common fillers and the applications they can be used for.

Glass

Glass is the most common type of filler for PTFE tubing. This type of filler is typically made from the E-glass fiber type. Glass fillers are ideal for hydraulic piston rings because they provide superb wear resistance, low creep, and excellent compression strength. The high compressive strength of glass fillers protects the tubing from becoming deformed over time. Glass fibers are made from either powder or fiber. Glass fiber delivers better creep resistance, and glass powder is available at affordable prices.

Carbon

Carbon fillers add multiple benefits to PTFE tubing. This includes increased compression strength, wear resistance, hardness, and thermal conductivity (which improves heat distribution), as well as reduced absorbency. Also, adding graphite improves the wear and friction properties of carbon. Because carbon is extremely inert, the chemical has only a slight impact on the filler’s chemical resistance.

Graphite

Graphite is a stable crystalline form of high purity carbon. The element occurs naturally in many rocks. You would normally use graphite in pencils and as moderators in nuclear reactors. Graphite has a flaky structure and offers excellent dry lubrication, increased load bearing strength, and decreased wear to PTFE tubing fillers. Graphite is usually combined with other fillers, particularly glass and carbon.

Molybdenum Disulfide

Molybdenum Disulfide (MoS2), is a silvery black compound made from molybdenum and sulfur. MoS2 is usually combined with glass or bronze. When added to HPTE tubing fillers, MoS2 lowers friction, decreases stick-slip properties, enhances wear resistance and stiffness, and adds deformation resistance. This element is somewhat inert, and the only way you can dissolve MoS2 is with oxidizing acids.

Bronze

Bronze, an alloy of copper, provides great wear resistance and thermal conductivity to FTPE tubing fillers. Fillers made with bronze are more abrasive than other compounds, but you can fix this by adding MoS2 (molybdenum disulfide) or graphite. Applications involving bearing and piston rings generally use PTFE tubing fillers with a ratio of 55% bronze to 5% MoS2.  To make this type of filler, manufacturers add bronze by weight, typically from 40-60%.

Ekonol

Ekonol is a type of polyester. This composite material is aromatic and is known for being thermally stable. Along with dimensional stability and high strength, ekonol fillers provide high temperature, wear, and corrosion resistance to PTFE tubing. Ekonol is used in rotary applications because the material won’t erode compatible metal surfaces. Ekonol fillers are used in applications involving packing sets, compressor ring sets, seal sets (“O” rings, spring-loaded, lip, etc.), self-lubricating bearings, and rotor or vane style process pumps.

Polyimide

Polyimide is another type of polymer filler that offers superb wear and abrasion resistance. This type of filler has one of the lowest friction properties. This property allows polyimide to operate amazingly in dry applications, reducing maintenance costs of applications. PTFE tubing with polyimide fillers won’t erode compatible metal surfaces, including soft ones like brass, stainless steel, aluminum, and plastic. These properties, along with high purity and low outgassing, make polyimide ideal for use in vacuum, space, and semiconductor industries.

You can find out more about choosing the right filler for PTFE tubing by visiting Tef-Cap Industries Inc.’s website.

Comments

Comments are closed.