Pneumatic Tubing Pressure Rating & Temperature Derating Guidelines
Use working pressure for the exact model and stated operating conditions. Do not use burst pressure as a service limit, or assume the separately listed maximum pressure and maximum temperature apply simultaneously. Confirm units and temperature-related limits.
Part of the pneumatic tubing guide.
Temperature Derating Factor Multipliers for Polymer Tubing
As operating temperature rises above room temperature (23°C / 73°F), polymer tensile strength decreases, requiring continuous working pressures to be derated using the following engineering multiplier factors:
| Operating Temperature | Polyurethane (PU / PUR) | PA12 Nylon | PA6 Nylon | FEP / PFA Fluoropolymer |
|---|---|---|---|---|
| 23°C (73°F) | 1.00 (100%) | 1.00 (100%) | 1.00 (100%) | 1.00 (100%) |
| 40°C (104°F) | 0.75 (75%) | 0.85 (85%) | 0.88 (88%) | 0.95 (95%) |
| 60°C (140°F) | 0.50 (50%) | 0.70 (70%) | 0.75 (75%) | 0.85 (85%) |
| 80°C (176°F) | 0.30 (30%) | 0.55 (55%) | 0.60 (60%) | 0.75 (75%) |
| 100°C (212°F) | Not recommended | 0.40 (40%) | 0.45 (45%) | 0.65 (65%) |
| 150°C (302°F) | Exceeded | Exceeded | Exceeded | 0.45 (45%) |
| 200°C (392°F) | Exceeded | Exceeded | Exceeded | 0.30 (30% – PFA only) |
Example Calculation: A 6×4 mm PU tube rated for 8 bar at 23°C has an effective maximum working pressure of 8 bar × 0.50 = 4.0 bar when operating continuously at 60°C.
Keep the pressure definitions separate
Working pressure and burst pressure describe different conditions. A burst-pressure value should not be used as an operating limit.
State the temperature condition
Include both the operating temperature range and any temperature conditions associated with a supplied pressure figure. Do not compare figures without checking their stated conditions and units.
Use the applicable product data
Request the correct datasheet for the material and model. Suitability must be confirmed against the actual medium, pressure, temperature and installation requirements.
Pneumatic tubing pressure rating: what to confirm
A pneumatic tubing pressure rating belongs to a stated model and set of conditions. Confirm the pressure definition, medium, temperature, duty cycle and fitting limits. A family name or a burst-pressure result is not an operating approval.
Review each material against its own data
- Polyurethane tubing pressure rating: use the selected PU model and the stated conditions.
- PFA tubing pressure rating and temperature rating: check the PFA model documentation; do not borrow an FEP limit.
- FEP tubing temperature rating: confirm the FEP model and any pressure-related temperature conditions.
- Polyethylene tubing temperature rating: identify the PE model and intended medium before comparing limits.
The product data sheets do not establish a complete pressure–temperature derating curve for every range. Request missing conditions rather than calculating an unsupported combined rating.
What to request from the supplier
Request the selected model, pressure definition, test temperature, applicable pressure–temperature relationship and installation limitations. Request these values from the supplier and record them with the rating.
Review product specifications →
What a named source says about pressure and temperature
Pressure ratings are normally stated at a reference temperature. A US compressed-air distributor’s listing for polyurethane tubing carries this caution:
“working pressure decreases significantly above 75º F”
Treat this as a prompt to ask for the pressure–temperature relationship of the exact model. It is a third-party remark about another supplier’s tubing and is not a rating for YUANNAI TUBE products.
References
- Compressed Air Systems, Inc. — Polyurethane Tubing (product listing, accessed 21 October 2026).
Frequently asked questions
What safety factor is standard between burst pressure and working pressure (3:1 vs 4:1)?
In industrial pneumatics and fluid transfer, the standard engineering design safety factor is between 3:1 and 4:1 at room temperature (23°C). For example, a tube with an 8 bar working pressure rating is engineered with a minimum burst pressure of 24 bar to 32 bar. This margin accommodates momentary hydraulic surges, rapid valve closures, and pressure pulsation.
Why does polyurethane tubing pressure rating drop rapidly above 40°C?
Polyurethane is an elastomer with a relatively low glass transition temperature and soft polymer segments. As thermal energy increases above 40°C, intermolecular van der Waals bonds relax rapidly, lowering the tensile modulus. For circuits operating between 50°C and 100°C, semi-rigid PA12 nylon or fluoropolymers (FEP/PFA) provide substantially higher residual pressure retention.
Does working pressure change with temperature?
Yes. As temperature rises, the material’s strength decreases and the working pressure must be derated to the value stated at that temperature in the model table.
Is burst pressure the same as working pressure?
No. Burst pressure is the failure point in testing. Working pressure already includes a safety factor. The two figures must never be compared or substituted.
Can I use the 23C rating at 60C?
No. Use the rating at the actual operating temperature. If the table does not list that temperature, confirm with the supplier before proceeding.
Sources and scope
- PU Tubing — English data sheet (v3-20261020)
- PA6 Nylon Tubing — English data sheet (v4-20261020)
- PA12 Nylon Tubing — English data sheet (v5-20261020)
- High-Pressure Composite Tubing — English data sheet (20261020)
Use these documents for the identified product models and stated test conditions. General material comparisons and selection checklists do not establish a different grade’s rating, fitting compatibility or project approval. Confirm the exact model, medium, temperature, pressure and required evidence before ordering.
Content review: zhangkexin · Marketing
Review scope: market information and document references.
