Case NE-3 — EV Liquid Cooling Tube
Hardware: LY Series Direct-Pressure Decay Tester + LT-G01 Bend-Clamp Inner-Expansion Quick Connector
| Specification | Value |
|---|---|
| Test Pressure (Nominal) | 325 kPa (13–350 kPa window) |
| Accept Range | 298–350 kPa |
| Leak Threshold | ±1.0 kPa pressure decay |
| Cycle Breakdown | Charge 6 s / Stabilize 8 s / Measure 8 s / Exhaust 1 s |
| Total Cycle Time | 23 s |
| Detection Method | Direct pressure decay |
Problem
As EV battery pack energy densities increase, aluminum liquid cooling tubes are routed through increasingly constrained packaging spaces, resulting in complex bent geometries. Production volumes demand a leak test cycle under 30 seconds per part. Conventional fixture designs apply axial clamping force to tube ends — deforming thin-wall aluminum and generating false rejects that inflate scrap rates.
Solution
The LY Series direct-pressure tester executes a four-phase automated sequence (charge → stabilize → measure → exhaust) with on-board thermal drift compensation, eliminating pressure variance caused by shop-floor temperature fluctuation — the leading source of false rejects in high-pressure cooling circuit testing. The LT-G01 bend-clamp inner-expansion connector seals from the inside of the tube bore, applying zero axial or lateral force to the tube wall. This preserves dimensional integrity during testing and accommodates tube ODs from 6 mm to 52 mm without tooling changeover.
Result
- 23-second takt time — compatible with high-volume EV assembly line throughput
- ±1.0 kPa leak acceptance window maintained across full production shift without thermal recalibration
- False-reject rate driven to near-zero after eliminating axial-force fixture deformation
- Deployed on battery pack assembly lines producing liquid-cooled modules for passenger EV platforms