ITT Engineered Valves
Pure-Flo Grade TME PTFE Diaphragm
The Pure-Flo Grade TME diaphragm combines a modified-PTFE product contact surface with a specially formulated EPDM backing cushion in a robust two-piece construction. It brings the chemical inertness of PTFE to the wetted side while the elastomer cushion provides the resilience a diaphragm needs to seal.
Product Benefits
- Broad chemical compatibility: A PTFE face gives broad chemical compatibility and a clean, low-interaction product surface where plain elastomers would degrade or be unsuitable.
- Floating tube nut: The two-piece design with a floating tube nut spreads closing forces evenly, reducing cold flow and point loading.
- No delamination risk: Unlike bonded constructions, the two-piece build has no bonded interface that can separate.
- Tuned for thermal cycling: The construction minimizes compression and extrusion of the backing cushion, so sealing performance holds up through repeated steam and cleaning cycles.
Where It's Used
- Across the Pure-Flo range: Grade TME fits Pure-Flo hygienic diaphragm valves from the smallest fractional sizes up to large line sizes.
- EnviZion companion variant: A companion variant exists for EnviZion valves.
- Hot and aggressive duty: It is the natural choice in biopharmaceutical services that run hot, cycle between steam and process, or carry media too aggressive for an all-elastomer diaphragm.
Good to Know
- FDA-compliant materials: The PTFE contact layer and the elastomer backing each meet the relevant FDA requirements.
- USP Class VI: The diaphragm carries USP Class VI compliance, supporting hygienic validation.
- Different seating behavior: PTFE-faced diaphragms seat differently from soft elastomers, which is why the matched two-piece compressor arrangement matters.
- Follow assembly practice: Keeping to the manufacturer's assembly practice preserves the even force distribution the design is built around.
