Spacers, Bellows, Strainers & Accessories
Spacers, Bellows, Strainers & Accessories
Request a quotation
Full technical data and dimensions
Request the datasheet
PTFE Moulded High Pressure Bellow
Moulded PTFE expansion joint, NB 1" to 24"
Moulded PTFE expansion joint with stainless reinforcing rings — absorbs thermal movement, vibration and misalignment in lined lines. NB 1" to 24", 50 mm to 150 mm face to face.
| Product type | Moulded PTFE expansion bellow |
|---|---|
| Body / steel grade | Flanges IS 2062 plate / ASTM A 105, reinforcing rings Stainless steel |
| Lining material | PTFE |
| Liner standard | Bellow ASTM D 1457 / ASTM D 4894-19 |
| Lining options | Virgin or anti-static (conductive black) PTFE to ASTM D 4894 & D 4895, PFA to ASTM D 3307, FEP to ASTM D 2116 |
| Flange standard | ASME/ANSI B16.5 |
| Flange class | Class 150 standard; Class 300 on request |
| Size range | NB 1" to NB 24" |
Product overview
What it does, and where it fits.
A rigid lined pipeline has nowhere to put thermal expansion. Left unrelieved, that movement loads flanges, cracks liners and pulls equipment nozzles out of line. A PTFE bellow absorbs it in convolutions of solid fluoropolymer, so the wetted path stays inert while the line is free to move.
The moulded bellow is formed to shape rather than machined, which suits the higher production volumes and the standard convolution profiles. Stainless steel reinforcing rings sit between the convolutions to carry pressure, and the flanges are IS 2062 plate or ASTM A 105.
Face-to-face runs from 50 mm at NB 1" to 150 mm from NB 8" upward. The range extends to NB 24", further than most items in the catalogue. Special convolution counts, Class 300 flanges, stainless flanges and zinc-plated adjustment screws are all available on request.
Features
Built into every unit.
- Moulded PTFE convolutions to ASTM D 1457
- Stainless steel reinforcing rings between convolutions
- NB 1" to 24" — the widest size range in the lined catalogue
- Face to face 50 mm to 150 mm
- Special convolution counts and adjustment screws on request
Benefits
Why it earns its place in the line.
- Absorbs axial, lateral and angular movement that would crack a rigid lined spool
- Isolates pump and compressor vibration from the pipework
- Fully inert PTFE wetted path across the flexible element
- Outstanding corrosion resistance to aggressive organic and inorganic chemicals across a wide temperature range
- Non-stick, non-wetting bore — low surface energy keeps product moving and simplifies cleaning
- Chemically inert and pure; no additives, plasticisers, stabilisers or lubricants to contaminate the process fluid
Applications & industries
Where it is specified.
Typical applications
- Thermal expansion take-up in lined process lines
- Vibration isolation at pump and blower connections
- Absorbing settlement and misalignment between equipment
- Protecting glass-lined and brittle equipment nozzles from pipe loads
Industries served
- Chemical processing
- Pharmaceutical
- Petrochemical
- Oil & gas
- Power generation
- Pulp & paper
- Mining & metallurgy
- Agrochemicals & dyes
Technical data
Specification for PTFE Moulded High Pressure Bellow.
Figures below are for this product only — every item in the range carries its own dimension table.
| Product type | Moulded PTFE expansion bellow |
|---|---|
| Body / steel grade | Flanges IS 2062 plate / ASTM A 105, reinforcing rings Stainless steel |
| Lining material | PTFE |
| Liner standard | Bellow ASTM D 1457 / ASTM D 4894-19 |
| Lining options | Virgin or anti-static (conductive black) PTFE to ASTM D 4894 & D 4895, PFA to ASTM D 3307, FEP to ASTM D 2116 |
| Flange standard | ASME/ANSI B16.5 |
| Flange class | Class 150 standard; Class 300 on request |
| Size range | NB 1" to NB 24" |
| Temperature range | Continuous service to 260 °C (PTFE melting point 327 °C, PFA 306 °C, FEP 260 °C) |
| Pressure rating | ASME/ANSI B16.5 Class 150 flanges as standard; Class 300 available on request |
| Manufacturing standard | ASTM F 1545 |
| Spark testing | Every lined component spark tested at 5000 × E volts (E = liner thickness in mm), to a maximum of 15 000 V |
| Hydro testing | Hydrostatic or pneumatic test according to the lining technique; hydrostatic test on components with vent holes |
| Inspection | Dimensional and visual examination of liner and steel parts — weld aspect, overall dimensions, collar size, liner thickness, surface flaws and paint thickness |
| External protection | Zinc epoxy primer, minimum 60 μm dry film, over steel sand-blasted to SA 2.5 |
| Certification | EN 10204 3.1 mill certificates and FDA certification for the fluoropolymer available on request |
| Face to face | 50 mm to 150 mm |
| Size | Face to face L (±2) | PTFE | PFA | FEP |
|---|---|---|---|---|
| 1" | 50 | ✓ | — | — |
| 1.5" | 55 | ✓ | — | — |
| 2" | 70 | ✓ | — | — |
| 3" | 100 | ✓ | — | — |
| 4" | 100 | ✓ | — | — |
| 6" | 100 | ✓ | — | — |
| 8" | 150 | ✓ | — | — |
| 10" | 150 | ✓ | — | — |
| 12" | 150 | ✓ | — | — |
| 14" | 150 | ✓ | — | — |
| 16" | 150 | ✓ | — | — |
| 18" | 150 | ✓ | — | — |
| 20" | 150 | ✓ | — | — |
| 24" | 150 | ✓ | — | — |
All dimensions in mm. Moulded PTFE only — the catalogue marks PFA and FEP as not applicable for this item.
Available on request
- Special numbers of convolutes
- ANSI B16.5 Class 300 flanges
- Stainless steel flanges
- Zinc plated adjustment screws
FAQ
Questions we are asked about this item.
It depends on the number of convolutions, which is why special convolution counts are offered. Send the axial, lateral and angular movement you need to absorb and we will confirm the build.
Both cover NB 1" to 24" at identical face-to-face dimensions. Moulded units are formed to standard convolution profiles; machined units are cut from solid stock and suit non-standard geometry. Ask us which fits your duty.
On unanchored lines, usually yes, to stop pressure thrust over-extending the bellow. Zinc-plated adjustment screws are listed as an available option.
Related products
Commonly specified alongside PTFE Moulded High Pressure Bellow.
Lined Pipes & Spools
Lined Pipes & Spools
Spacers, Bellows, Strainers & Accessories
Enquiry
Tell us your line size — we'll confirm the spec.
Send the bore, the media, the temperature and pressure, and the flange standard you work to. Drawings and custom sizes welcome.
Not sure which spec fits your process?
Send your requirement — media, temperature, pressure, dimensions — and we'll recommend the right product or fabricate it.
Talk to an engineer