Liquid cooling
Liquid-Cooling Hose Assemblies: Materials, Connections, and Sourcing
A hose assembly is the hose, the end connections, and the tests run on that build. The elastomer name does not settle the fluid or the fittings.
On this page
The hose, the end fittings, and the way the assembly is made and tested all belong in the request. A catalog sentence that names a rubber does not show that the hose is approved for your coolant, your pressure, or your quick disconnect. Rust Belt Industrials does not assemble or pressure-test hoses.
The requirements that define a hose assembly
Gates publishes data-center products that include Data Master MegaFlex cooling hose, Data Master data center cooling hose, UQD couplings, UQDB blind-mate couplings, and pumps. The family page names those lines and does not print a compound or a pressure. The Data Master product page describes a zinc-free, peroxide-cured EPDM tube and says that tube can withstand a wide range of coolant mixes, including PG25. The Data Master MegaFlex spec sheet dated 2026 describes the same kind of tube, a temperature range of -40°F to 212°F, and a working pressure of 150 psi across the sizes on that sheet. Data Master Eco, in Gates's 2025 family brochure, is a halogen-free tube and cover. That brochure does not call Eco an EPDM hose. CPC publishes couplings and seal options, not the hose. A complete assembly request has to join those pieces on purpose.
- The approved fluid, including concentration if the design states one.
- The hose specification or the approved equivalent.
- Both end fittings, including the interface family and size.
- Length, bend limits, and the environment along the route.
- Cleanliness, inspection, and the test the assembly must pass.
Materials and operating conditions
Use the document that approves a material for the fluid you run. The pages opened for this guide do not support a rule that one elastomer is safe for every coolant or every data-center loop.
Approved fluid and material documentation
OCP's UQD specification v2.0.0 is written for non-combustible single-phase water and glycol, and it points suppliers to OCP fluid guidelines for wetted materials. CoolIT says its stainless manifolds are validated for 25 percent propylene glycol and that other chemistries need validation. CPC says Everis couplings offer EPDM and FKM seals and are used with coolants that include dielectric fluids. Those statements are about couplings and manifolds, or about a specification's scope. They are not a hose compound. Ask the hose maker for the compatibility note that names your fluid.
Pressure, temperature, and routing constraints
Pressure, temperature, and minimum bend belong on the hose data sheet for the specific hose, at stated conditions. For Data Master MegaFlex, use the 2026 spec sheet's 150 psi working pressure and -40°F to 212°F range only for the sizes that sheet covers. The family landing page does not repeat those numbers. Write the conditions your design uses, and ask the supplier which hose page meets them. Routing adds length, the tightest bend, motion, and how close the hose sits to a hot surface or a service path. Manifold mounting changes that path. Coupling choice changes the ends.
Connections and routing
End fittings can be a quick disconnect, a barb, a port thread, or a fitting the manifold already has. Gates lists UQD and UQDB couplings next to its cooling hoses and does not, on the family page, show a finished assembly part number that joins a named hose to a named coupling. CPC lists termination styles on the Everis cold-plate page, including straight and elbow, and does not specify the hose. The maker of the hose has to approve the attachment method. This page does not describe how to crimp a fitting.
What to send an assembly supplier
The template is a local request. Nothing in it is uploaded, and filling it in does not place an order.
How to check supplier scope
Three roles get confused on one purchase order. The hose manufacturer publishes the hose. The coupling manufacturer publishes the end. The assembler cuts, attaches, cleans, and tests. One company can hold more than one role. Gates publishes both hoses and UQD-family couplings, which shows a hose maker can also publish couplings. That still does not identify who will build your assembly or whether that shop is allowed to attach the fitting to that hose.
| Role | What you can learn from a catalog | What to confirm |
|---|---|---|
| Hose manufacturer | A hose family and, on a part page, the compound and ratings. | The exact hose, the fluid approval, and whether an equivalent is allowed. |
| Coupling manufacturer | The interface family, the mating method, and the seal options. | The part number, the specification version, and the end that faces the hose. |
| Assembler | Often not visible from the hose brand alone. | That this shop can build the listed hose and fittings, and which test record ships with the assembly. |
Questions about sourcing cooling hoses
Can any EPDM hose be used?
The sources reviewed here do not say that. OCP's UQD specification says the socket hose barb is intended for reinforced EPDM hose and tells the buyer to consult the coupling supplier and the tube supplier for other tubes. Gates publishes a peroxide-cured EPDM tube on Data Master and on Data Master MegaFlex, and a halogen-free tube on Data Master Eco. CPC lists EPDM as one Everis seal option, which is a seal, not a hose. A hose labeled EPDM still needs the fluid, temperature, and pressure approval for that hose. If your document names a specific hose, ask before you substitute another EPDM product.
Who verifies the connections?
The assembler, against the fitting and hose instructions those manufacturers publish, and the design owner, against the loop requirements. A distributor that resells a coupling has not, by that fact, verified the crimp or the clamp. Ask which party performs the assembly and which record you will receive.
What documents should accompany an assembly?
The hose identity, the fitting identity, the length, the fluid it was cleaned for, and the test that was performed. If the interface is an OCP UQD or UQDB size, the size code and specification version belong on the same sheet. CoolIT's leak-test statement is about its manifolds, not about a hose shop. Ask the assembler for the assembly's own test.
Sources
Compound and pressure figures above come from the Data Master product page and the 2026 MegaFlex spec sheet, not from the family landing page. Where a fact was absent from those documents, it stays absent.