Semi-Welded Plate Heat Exchangers
The Perfect Balance: Laser-Welded Sealing Security with Frame Serviceability.
Get a Custom Engineering Quote
Technical Overview
Our Semi-Welded plate heat exchangers employ a unique plate pack design made of laser-welded plate pairs (cassettes). The aggressive, volatile, or high-pressure fluid securely flows inside the hermetically welded cassette channels, while the secondary cooling/heating utility fluid flows through gasketed channels. This hybrid design ensures hazardous materials remain safely contained while preserving the ability to open the unit for cleaning.
Engineering Specifications
| Cassette Welding | Continuous Automated CO2/Nd:YAG Laser Weld |
| Max Operating Pressure | 30 BAR to 40 BAR |
| Temperature Range | -40°C to +180°C |
| Cassette Metallurgy | SS316L, Titanium Gr.1, Hastelloy C-276 |
| Gasketing | O-Ring type field-replaceable port gaskets (Chloroprene/PTFE) |
| Testing Protocols | 100% Helium Leak Tested per Cassette |
Industries & Applications Served
Ammonia Refrigeration
Safely contains volatile R717 (Ammonia) inside welded cassettes for industrial chilling and freezing plants.
Aggressive Chemical Cooling
Ideal for sulfuric acid, hydrochloric acid, and caustic soda processing where gasket degradation is a severe risk.
Pharmaceutical Processing
Isolates high-purity API product streams from utility cooling water to prevent any risk of cross-contamination.
Petrochemical Refining
Handles hazardous hydrocarbons and sour gas streams safely under fluctuating high-pressure environments.
Why Choose PAL Engineers
Hazardous Media Containment
By confining toxic, volatile, or highly aggressive fluids strictly within the laser-welded plate pairs, we eliminate the risk of external leakage or catastrophic gasket failure.
90% Gasket Reduction
The semi-welded geometry eliminates all gaskets on the aggressive media side, leaving only highly durable port rings, drastically reducing long-term maintenance costs and downtime.
Dynamic Stress Resistance
The laser-welded cassettes naturally absorb mechanical stress and pressure shocks much better than fully gasketed units, ensuring long fatigue life in pulsating systems.
