A loop that fails at month nine failed at goods-in
Four test methods run against every accepted lot, each with one inspection record.
ASTM D1599 hydrostatic failure · ISO 1817 immersion · ASTM D1149 ozone cracking · ASTM D5470 thermal transmission
Which test catches which failure
Rupture and thread stripping.
Swell, extraction and precipitate.
A cracked cover is a permeation path.
An interface resistance that drifts.
Incoming inspection
Bore is gauged against the drawing, not a nominal size.
| Inside diameter, −6 | 9.5–10.3 mm |
|---|---|
| Outside diameter, −6 | 15.4–16.4 mm |
| Minimum bend radius at −4 | 24.5 mm |
| Minimum bend radius at −6 | 37 mm |
| Inspection record | one per lot, naming the drawing revision |
The method and the procedure
ASTM D1599 short-time hydrostatic failure testing, current revision ASTM D1599-18(2024). Pressure medium: deionised water or PG25, purged of air.
The two factors, and the failure list
| Hydrostatic proof | 1.5× the maximum allowable working pressure |
|---|---|
| Minimum burst | 3× MAWP, the Open Compute Project floor |
| Jumper hose | 1.38 MPa working against 5.5 MPa burst |
| Ratio | 4.0× |
| Hose assembly | hose rupture · thread stripping |
|---|---|
| Coupling | thread stripping · O-ring deformation · leakage on disconnect |
| Manifold | weld rupture · deformation |
ISO 1817 immersion
| Method | volume swell, mass change and extraction in the service fluid |
|---|---|
| Conditions | 168 h at 70 °C in PG50, swell and mass change reported |
| Published limit | none for this hose class; a swell figure needs the model's own report |
| What it catches | a sulphur-cured inner rubber releasing precipitates into the coolant |
| Where they lodge | cold-plate microchannels 100–400 µm wide |
The service fluid.
Per model report.
Not supplied for this service.
Ozone cracking and storage
Method
ASTM D1149-18(2025), surface ozone cracking in a chamber.
Mechanism
Ozone attacks the cover compound. A cracked cover is a permeation path.
Storage
Bagged, out of sunlight, away from motors and welders.
Shelf life
Elastomer shelf-life reviews find no justification for a shelf life shorter than 3 years.
What a W/m·K figure does not mean
| Method | ASTM D5470 returns apparent impedance at a controlled pressure and thickness |
|---|---|
| Consequence | every thermal part carries impedance at 10, 30 and 50 psi |
| Grease | 3.5 W/m·K · 0.02 °C·in²/W at 30 psi · 0.05 mm bond line |
| Sheet | 8.5 W/m·K · ≤0.0078 °C·cm²/W over 0.20–1.0 mm |
| Plane | pads and greases are through-plane; graphene figures are in-plane, in a separate column |
From test to carton
| Hose | coiled and bagged, layline readable |
|---|---|
| Cartridges | original wrap, micron grade labelled |
| Sensing rope | on a reel, connector protected |
| Pads | flat-packed, never folded |
| Documents | packing list · commercial invoice · certificate of origin · batch inspection record · datasheet per model code |
Flame rating the EPDM compound is specified to.
Available upon request.
Immersion method: volume swell, mass change, extraction.
Available upon request.
Short-time hydrostatic failure testing, run at goods-in.
Available upon request.
Certification names appear on the badge cards. A third-party document is not reproduced on this site.