Project Overview
Application: Industrial Inverter and High-Power Power Equipment Cooling
Product: Liquid Cold Plate
Customer Location: Germany
Industry: Industrial Power Equipment Manufacturer
Material: Aluminum 6061-T6
Manufacturing Process: Friction Stir Welding (FSW) + CNC Machining + Reliability Testing
A German industrial equipment manufacturer required a reliable liquid cooling solution for IGBT power modules installed inside industrial inverters.
The customer’s previous liquid cold plate supplier used conventional TIG welding for flow channel sealing. During long-term operation, some products developed micro-leakage issues caused by welding fatigue cracks under vibration conditions.
Jindu Tech provided a new liquid cold plate solution using friction stir welding (FSW) technology, improving weld strength, fatigue resistance, and long-term sealing reliability.
Initial Problem: Leakage Risk from Improper Welding Process
The customer’s previous supplier used conventional TIG welding for sealing the cooling channels.
Although the products passed initial pressure testing, long-term vibration conditions caused fatigue stress around the welded areas. This resulted in micro-cracks, coolant leakage, and potential damage to IGBT power modules.
The customer required a new manufacturing solution with:
• Higher weld strength
• Better fatigue resistance
• Long-term leak-proof performance
• Stable operation under vibration conditions
Customer Requirements
• Material: Aluminum 6061-T6
• Cooling power requirement: Approximately 1.2kW
• Application temperature requirement: IGBT junction temperature below 85°C
• Flow rate: 4L/min
• Coolant: 50% ethylene glycol water solution
• Contact surface flatness: ≤0.1mm
• Initial prototype quantity: 5 sets
• Expected annual demand: 500 sets
• Required 100% air leakage testing: 10Bar pressure, holding time ≥5 minutes without pressure drop
Jindu Tech Engineering Solution
Replacing Conventional Welding with Friction Stir Welding (FSW)
After evaluating the original design, Jindu Tech identified that conventional TIG welding generated higher heat input and residual stress in the weld area.
To improve reliability, Jindu Tech replaced the welding process with Friction Stir Welding (FSW).
FSW is a solid-state welding process that produces strong joints with reduced defects compared with traditional fusion welding methods. The process provides excellent fatigue resistance and is suitable for liquid cold plates requiring long-term sealing performance.
Optimized Cooling Channel Design
Jindu Tech also optimized the internal cooling channel structure.
The original single-channel design was improved into a multi-channel parallel structure, reducing flow resistance while improving coolant distribution and temperature uniformity across the heat dissipation area.
Precision CNC Machining
The liquid cold plate body was manufactured through precision CNC machining to ensure:
• Accurate cooling channel dimensions
• Stable product geometry
• Required surface flatness
• Reliable assembly compatibility
Testing and Validation
To verify product reliability before mass production, Jindu Tech performed comprehensive testing:
✓ 100% air leakage test (10Bar pressure, 10 minutes holding time, zero pressure drop)
✓ Pressure cycle testing (0-10Bar, 1000 cycles without leakage)
✓ Vibration testing according to IEC 60068-2-6
✓ Dimension inspection and flatness inspection
✓ Customer equipment validation testing
Prototype Validation and Mass Production
After prototype production, the liquid cold plate completed all required validation procedures.
The customer confirmed that the FSW-manufactured cold plate met the requirements for thermal performance, sealing reliability, and mechanical stability.
The project successfully moved from prototype development into mass production. Jindu Tech has continued supplying liquid cold plate solutions for the customer’s industrial applications.
Final Results
The FSW liquid cold plate solution successfully solved the leakage risk caused by the previous welding process.
After installation testing:
• No leakage was detected after 500 hours of continuous operation
• IGBT junction temperature was controlled below 82°C
• Product reliability met the customer’s long-term operating requirements
The customer selected Jindu Tech as a reliable liquid cold plate supplier for ongoing production needs.
Why Jindu Tech Was Selected
This project required more than a standard cooling plate. Jindu Tech provided a complete engineering solution:
• Welding process optimization
• FSW technology application
• Customized cooling channel design
• Precision CNC machining
• Leakage prevention testing
• Prototype-to-mass-production support
Through process innovation and engineering capability, Jindu Tech helped the customer achieve a safer and more reliable liquid cooling solution.
