Polymax Ltd

Description

NBR (Nitrile) is the most cost effective and commonly available O-ring material. Ideal for use as seals for pumps, drive belts, and other general engineering applications in the hydraulic and pneumatic industry. NBR is good for applications where the O-ring is exposed to fats, greases and animal or vegetable oils.

For applications requiring contact with diesel or temperatures higher than 120°C you may wish to consider Polymax FKM (Viton®) O-rings.

Temperature Range

• Up to 90°C (Intermittent)
• Down to -30°C

Recommended temperature range -20°C to +90°C

Chemical resistance

• Many hydrocarbons
• Fats
• Oils & Gasoline
• Petroleum based hydraulic fluid (HFD-R)

• Ozone
• Esters
• Retones
• Aldehydes
• Chlorinated
• Nitro Hydrocarbons

Description

FKM (Viton®) O-rings have excellent chemical resistance and can be used at temperature range of between 15°C and 200°C. Although generally more expensive than NBR (Nitrile) O-rings, FKM has found wide acceptance in the aircraft, automotive and chemical industries.

The terms FPM, FKM and Viton® can lead to incorrect interpretations. These designations stand for one single base material: fluorocarbon rubber.

Polymax is also able to supply specially compounded FKM O-rings meeting Norsok M710, FDA, USP Class VI, UL94 V0, EN549, Viton® A, B, G, GF, GLT, GFLT, ETP standards on special request. Please contact us for further information.

Temperature Range

• Up to 200°C (Intermittent)
• Down to -15°C

Recommended temperature range -10°C to +180°C

Chemical resistance

• Mineral oil and grease, ASTM oil No. 1, and IRM 902 and IRM 903 oils
• Non-flammable hydraulic fluids (HFD)
• Silicone oil and grease
• Mineral and vegetable oil and grease
• Aliphatic hydrocarbons (butane, propane, natural gas)
• Aromatic hydrocarbons (benzene, toluene)
• Chlorinated hydrocarbons (trichloroethylene and carbon tetrachloride)
• Gasoline (including high alcohol content)
• High vacuum
• Very good ozone, weather and aging resistance

Not compatible with:
• Glycol based brake fluids
• Ammonia gas, amines, alkalis
• Superheated steam
• Low molecular weight organic acids (formic and acetic acids)

Description

EPDM rubber is a terpolymer of ethylene, propylene and diene monomers.
O-rings manufactured from EPDM exhibit an excellent resistance to weathering and ozone, water and steam.

General purpose EPDM O-rings are manufactured using a sulphur based curing system, these are suitable for use up to +120°C whereas peroxide cured
O-rings can be used up to +150°C. EPDM is particularly useful when sealing in brake systems that use fluids having a glycol (Dot 3 and 4) or silicone base (Dot 5).

Polymax peroxide cured EPDM O-rings have a series of approvals including ACS, WRAS, KTW, EN 681-1. Please contact us for further information.

Temperature Range

• Standard EPDM up to 120°C (Intermittant)
• Peroxide Cured up to 150°C
• Down to -30°C

Recommended temperature range -20°C to 120°C

Chemical resistance

• Hot water and steam up to 149°C with special compounds up to 260°C
• Glycol based brake fluids (Dot 3 & 4) and silicone-based brake fluids (Dot 5) up to 149°C
• Many organic and inorganic acids
• alkalis
• Phosphate-ester based hydraulic fluids (HFD-R)
• Silicone oil and grease
• Many polar solvents (alcohols, ketones, esters)
• Ozone, aging and weather resistant

Not compatible with:
• Mineral oil products (oils, greases and fuels)

Description

Silicone (VMQ) rubber contains methyl and vinyl groups attached to the main silicone chain. Silicone O-rings are characterised by excellent resistance to temperature extremes and thermal cycling. Silicone rubber compound does not impart odour or taste, which makes it suitable for many food and pharmaceutical applications.

Silicone rubber however, has poor mechanical properties as compared to other elastomers and for this reason silicone O-rings are generally not used in dynamic applications. It is not suitable for use with silicone O-ring lubrication, PTFE alternatives should be used instead.

Temperature Range

• Up to 200°C (Intermittant)
• Down to -40°C

Recommended temperature range -20°C to +180°C

Chemical resistance

• Dry heat
• High - aniline point oils
• Chlorinated DI - phenyls
• Food processing applications
• Excellent ozone resistance.
• Water (Low temperature only)

Not compatible with:
• Most Petroleum fluids
• Ketones (MEK, Acetone)

Description

PTFE is a highly resilient O-ring material unaffected by virtually all known acids, alkalis and solvents. It is tough, abrasion resistant and capable of withstanding temperatures between -200°C to +250°C. It also possesses outstanding weather, ozone and electrical resistance. For this reason, it is the O-ring of choice for use in aerospace, food, pharmaceuticals and telecommunications industries.

Temperature Range

• Up to 250°C (Intermittant)
• Down to -70°C

Recommended temperature range -60°C to +230°C

Chemical resistance

• Excellent resistance to almost all chemicals
• Not subject to ageing, so a near infinite shelf / storage life
• Can be use in food, chemical and medical industries (among others)
• Low elasticity (memory), making it unsuitable for dynamic applications unless energised by suitable material (I.E. rubber)
• Low coefficient of friction

Not compatible with:
• Low compression vacuum sealing flanges
• High vacuum seals
• High temperature steam

Description

Chloroprene (or Neoprene / CR) was one of the first developed synthetic compounds, invented by DuPoint™ scientists in 1930. Chloroprene is a good multi-purpose material, it exhibits fair oil resistance and good ozone and weather resistance. A combination of both these properties is usually not found in other commonly available elastomers like NBR and EDPM.

Chloroprene is often used in refrigeration systems due to the excellent resistance to refrigerants such as Freon® (R12, R13, R21, R22, R113, R114, R115, R134A) and ammonia.

Temperature Range

• Up to 110°C (Intermittant)
• Down to -40°C

Recommended temperature range -30°C to +100°C

Chemical resistance

• Ammonia gas
• High Aniline point oils
• Refrigerants (Freons)
• Silicate esters
• Weather and Ozone

Not compatible with:
• Brake fluids
• Ketones
• Phosphate esters