Material specification page for ptfe thread seal tape in FKM (Viton®-type). Covers the grade designation (fluoroelastomer, typically 75 Shore A), corrosion and magnetic behavior, comparable grades and their trade-offs, and the sizes available to Trade series (PTFE thread sealing tape, colour-coded by density).
Why Choose FKM (Viton®-type) for PTFE Thread Seal Tape
Specified where temperature or chemical exposure exceeds nitrile. For ptfe thread seal tape, this matters when excellent resistance to heat, fuels, and most chemicals; poor with ketones and hot water/steam is the primary requirement.
Mechanical & Physical Properties
| Grade designation | fluoroelastomer, typically 75 Shore A |
|---|---|
| Magnetic response | Non-magnetic |
| Service temperature | approx. -20 °C to +200 °C |
| Corrosion characteristic | Excellent resistance to heat, fuels, and most chemicals; poor with ketones and hot water/steam |
Corrosion Behavior in Service
Carbon and alloy steel ptfe thread seal tape require a coating for corrosion protection. Zinc plating (with or without passivation) is the most common; hot-dip galvanizing is used for outdoor structural service; black-oxide is mainly a tarnish-prevention finish for tool-room use.
Comparable Grades
For ptfe thread seal tape, consider NBR where the service is ordinary mineral oil and the cost matters, or EPDM for hot water and steam, which attacks FKM. Elastomer selection is decided by the medium, the temperature range and whether the seal is static or dynamic — not by strength.
Sizes of PTFE Thread Seal Tape Available in FKM (Viton®-type)
| Colour | Density | Intended service | Notes |
|---|---|---|---|
| white | standard density | water and general plumbing | general purpose |
| pink | high density | water, larger threads | thicker, fewer wraps needed |
| yellow | high density | gas lines | gas-rated tape |
| green | oil-free, degreased | oxygen service | must be oxygen-clean |
| grey | with filler | stainless steel threads | reduces galling on stainless |

