SWEP B12 200kW LO cooling

Common issues

• Internal fouling from lube oil degradation products/varnish restricting flow and reducing heat transfer
• Cross-contamination between circuits following an internal braze/plate failure
• External corrosion at connections and nozzles, particularly with dissimilar-metal contact
• Reduced LO cooling capacity from partial blockage of the narrow plate channels
• Fatigue cracking of brazed joints from thermal cycling or pressure pulsation
• External fouling or scale build-up on the coolant-side if seawater or untreated fresh water is used
• Vibration-induced fatigue at pipework connections

Inspection checklist

• Check differential pressure across the LO side against the commissioning baseline
• Monitor outlet temperature/approach temperature against design to detect performance degradation
• Inspect the external shell and connections for oil weepage indicating an internal leak
• Check for external corrosion, especially at brazed end connections and mounting brackets
• Verify any fitted insulation is intact and not trapping moisture against the shell
• Check mounting/support brackets for vibration-related fatigue cracks
• Sample oil for coolant contamination if an internal leak is suspected
• Confirm associated pressure relief/safety devices are functional

Service intervals

Typical wear limits

Ranges are typical for this design class. Always confirm against the manufacturer documentation for your serial number.

Critical spares

• Complete replacement unit - brazed plate exchangers are fully sealed and cannot be reopened or re-plated in the field
• Gaskets/O-rings at pipe connections (flanged or threaded joints only, none internal)
• Isolation valves and associated pipe fittings
• Temperature and pressure sensors fitted to the circuit
• Mounting/support bracket hardware

Safety

• Hot surfaces on the LO-side piping and connections - burn hazard
• Pressurised system - isolate and depressurise fully before disconnecting any joint
• Risk of oil mist or spray if a connection is broken under residual pressure
• Confined space considerations if the unit is mounted in a tight engine room location

Class survey

Where part of a class-surveyed cooling system, typically falls under Continuous Survey Machinery. Class looks for pressure testing history, a fouling-related cleaning routine in the PMS, and evidence of leak-free operation. No internal survey is possible on a brazed unit - assessment relies on performance trending and external inspection.