Why Perform Heat Exchanger Integrity Inspections
Pasteurizers and general heat exchangers (HE) are commonly recognized as Critical Control Points by HACCP plans. An HE unit suffers huge amounts of thermal and mechanical stress during the normal exploitation period.
Risk of cross contamination of the product is possible if the plates/tubes develop defects. This could be cracking, micro-cracking, pitting or corrosion pinholes.
Sources of cross contamination are the service circuits – cooling or heating. Glycol and ice water circuits are the most common source of microbiological contamination.
As dismantling and opening the heat exchangers is time consuming and costly, the best solution is to perform regular NDT integrity inspections. Only after, if a unit fails a test, is open service required on the heat exchanger.
Bioscan LTD’s technician’s have over a decade of experience in the field, which ensures we can offer integrity testing services with a focus on following principles:
- No chemical residues after testing,
- Minimal plant downtime needed,
- Testing equipment suitable to transport by air.
Bioscan’s Heat Exchanger Integrity Inspection Procedure
Bioscan offers a gas testing method using hydrogen as a trace gas. When considering the size and agility of the hydrogen molecule, it makes it the perfect trace gas to penetrate and detect the smallest micro cracks and even the weakened stainless steel areas where the cracking will develop.
Bioscan’s Testing procedure is the following:
- Testing begins with pressurising the service side (cooling/heating) of the section with trace gas.
- At the product side constant air flow is established in a closed loop via a membrane pump.
- Hydrogen gas concentration is monitored on the product side.
- Measured values are recorded and analysed to determine the results.
- Results are classified as: PASS, TEMPORARY PASS or FAIL.
We have also developed our own unique control and data log software. After each measurement, an automatic report is generated and every measurement has its own unique test number.
Using the widely available tracer gas with the best sensor units on the market, Bioscan can provide the ultimate service.