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Leakage detection with SPX Gappscan

Plate Heat Exchanger Leakage Detection – Testex

How Testex Detects Leaks

When Testex was first introduced it was found that more than 30% of heat exchangers were shown to have defective plates. Regular testing enables problems to be eliminated before they develop into a major incident. Testex is a recognized method found in 3A standard T-603-07 as an accepted practice for the testing of HTST heat exchangers.

The Testex process consists of the detection of defective plates in the plate heat exchanger through Electrolytic Differential Analysis (EDA). EDA is used to determine if cross contamination is present. A consistent rise in the conductivity of the water indicates the presence of defective plates.

  • One side of the PHE filled with an electrolyte – usually sodium sulfate
  • Other side filled with water
  • Solution circulated using pumps
  • The pressure of the electrolyte is increased to create a differential pressure of between 30 psi to 100 psi
  • The conductivity of the water is monitored
  • Any consistent rise in conductivity of the water when pressure is applied indicates faulty plates

Features and Benefits

Features of Testex Leakage Detection Equipment:

  • The Testex range can pick up even the smallest crack
  • Testing is carried out under pressure
  • Utilizes state-of-the-art monitoring equipment
  • Identifies the occurrence of cross contamination without the PHE being dismantle
  • Adaptable to many models & sizes of PHEs’

Benefits of Testex Leakage Detection Equipment:

  • Provides the customer with plant safety assurance
  • Production conditions are simulated as closely as possible during the tests
  • Reduces false readings and human error
  • Plant down-time is drastically reduced. Plates & gaskets are not unduly stressed
  • A wide variety of PHE’s can be tested, in differing environments

Setting up a test for your heat exchanger, tank or vessel is simple:

  • Locate your SPX FLOW local contact
  • Provide specific details of your heat exchanger, heater coil, tank or vessel including model number, serial number, size and application
  • Specify test type - validation or routine preventative maintenance


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