How Danfoss Hansen Universal Quick Disconnect coupling (UQD) can meet the specific needs of thermal management applications
Danfoss · Danfoss Power Solutions
A short Danfoss Power Solutions article on selection criteria for quick-disconnect couplings in data-centre liquid cooling loops, positioning the UQD family as interchangeable with OCP UQD Rev 1.0.
On this page
Overview
The article lists the selection criteria: material and seal compatibility with water-glycol coolants, leakage risk and dry-break design, working pressure against the OCP specification, the effect of flow and pressure drop on cooling energy, thread and end-connection options, and colour coding to prevent hot/cold cross-connection.
On efficiency, UQD flow capacity is stated to be at least 25% higher than the OCP UQD Rev 1.0 requirement, which means lower pressure drop and so an effect on PUE. Working pressure exceeds the OCP requirement by 66% for size -02 and 57% for size -04.
For leakage and reliability it uses a flat-face dry-break design with dual sealing; couplings are 100% helium leak tested and can disconnect under pressure up to 5 bar. A stainless steel body and EPDM seals are chosen for corrosion resistance and water-glycol compatibility.
The family comes in sizes -02, -04, -06 and -08 with ORB, hose-barb and BSPP ends, and colour-coded sleeves and O-rings separate hot and cold circuits. This is one manufacturer's product article; the figures are the manufacturer's statements and no independent test data is included.
Key points
- UQD flow capacity is stated to be at least 25% higher than the OCP UQD Rev 1.0 requirement.
- Working pressure exceeds the OCP requirement by 66% for size -02 and 57% for size -04.
- Flat-face dry-break with dual sealing; couplings 100% helium leak tested; disconnection under pressure up to 5 bar.
- Stainless steel body and EPDM seals chosen for corrosion resistance and water-glycol compatibility.
- Sizes -02, -04, -06, -08 with ORB, hose-barb and BSPP ends.
- Colour-coded sleeves and O-rings identify hot and cold circuits.
Using it in design
- In the liquid-cooling catalogue store coupling size, OCP compliance, maximum working pressure, flow coefficient/pressure drop, disconnect-under-pressure limit and wetted materials.
- Check coolant chemistry against seal material.
- Include coupling pressure drop in the TCS loop hydraulic calculation.
- Require hot/cold colour coding in the rack manifold specification.
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Who should read it
Mechanical designers writing coupling and manifold specifications for in-rack liquid cooling loops.
Related standards
- OCP Universal Quick Disconnect (UQD) Specification Rev 1.0
Publication details
- Authors
- Danfoss Power Solutions
- Publisher
- Danfoss
- Year
- 2024
- Document number
- AC468060588597en-000101
- Document language
- English
- Source type
- Manufacturer
- Access
- Free to read
- Licence
- Copyright retained; citation only — the publisher’s terms apply to the original document
Citation
Danfoss Power Solutions (2024). How Danfoss Hansen Universal Quick Disconnect coupling (UQD) can meet the specific needs of thermal management applications. Danfoss. AC468060588597en-000101. https://assets.danfoss.com/documents/364276/AC468060588597en-000101.pdf
Events on this subject
- NVIDIA GTC
- SC26 – International Conference for High Performance Computing, Networking, Storage and Analysis
- Data Center World Middle East
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