PTFE or Teflon® as it is commonly known is a fluorocarbon based polymer and is usually the most chemically-resistant of all plastics while retaining excellent thermal and electrical insulation properties. This material is non-contaminating and accepted by many agencies for use in food services. This is used as a seat material in our steam and high temperature & pressure solenoid valves as well as some of our ball valves and butterfly valves.
Temperature range: -10°C to 120°C
RTFE (Reinforced Polytetrafluoroethylene)
RTFE (reinforced Teflon®) is mixed with a percentage of glass filler material to provide additional strength, stability and resistance to abrasive wear, and less permeation. This reinforcement permits higher pressures and temperatures than unfilled PTFE. RTFE should not be used in applications that attack glass, such as hydrofluoric acid and hot/strong caustics. We use a 15% glass filler in our stainless steel ball valve range to allow steam and higher temperatures/pressure than otherwise possible.
Temperature range: -20°C to 180°C
Colour: Slightly off White
Delrin® is DuPont’s trademark for Polyoxy-methylene. It is very rigid, does not undergo cold flow, and has an excellent combination of strength, hardness, stiffness, stability, abrasion resistance and low friction. Delrin is a great high pressure seat material allowing pressures up to 3000PSI (200 BAR) but declines quickly with heat.
Temperature range: 0°C to +60°C
Colour: glossy white
PEEK is a high temperature, semi-rigid elastomer offering a combination of chemical, mechanical and thermal properties. PEEK is excellent for water and steam applications at high temperatures and pressures to 6000 PSI (400 BAR) while providing good corrosion resistance.
Temperature range: -50°C to 200°C
EPDM has good abrasion and tear resistance while offering excellent chemical resistance to a variety of acid and weak alkaline-based media. It also has exceptional weather aging and ozone resistance. EPDM is susceptible to attacks by oils, therefore it is not recommended for applications involving petroleum oils, hydrocarbons, alcohols, strong acids or strong alkalines. EPDM also should not be used on compressed air lines.
Temperature range: -10°C 100°C
BUNA-N (Nitrile, NBR)
BUNA-N (NBR) is a general purpose polymer with good resistance to oil, water, solvents and hydraulic fluids. With good compression, strength and abrasion-resistance, NBR performs well with diverse media such as oils, alcohols, fatty acids, inert gasses or compressed air. We do not recommend using NBR with hydrocarbons as the solvents may attack the elastomer.
Temperature range: -10°C to 80°C
Viton® (Fluorocarbon, FKM)
Viton® is DuPont’s trademark name for Fluoroelastomer which is widely recognized for its chemical resistance. Its chemical compatibility spans a wide array of concentration and temperature ranges, as a consequence fluorocarbon elastomers have gained acceptance in a variety of applications. Viton offers excellent resistance to aggressive fuels and chemicals as well as media such as mineral acids, salt solutions, chlorinated hydrocarbons, and petroleum oils. This is standard in our fuel/petrochemical B55 & S55 series of solenoid valves. Viton should not be used in steam or hot water service.
Temperature range: -10°C to 100°C