PeneCert™ Test Services for Liquid Penetrant Testing

Some facilities apply penetrants on a one-off basis; others store penetrants in closed tanks or containers until used. However, most facilities use the immersion method, where excess penetrant is allowed to drain back after application to the part being tested. With the immersion method, tanks are often open to the environment, which increases the risk of contamination. Coupled with this contamination can be introduced from the part(s) under test.

Causes of contamination include:

• Water
  Contamination from water is the most common form of contamination. The water can come from pre-washed parts that are not fully dried, careless rinsing or from leakage from pipes. Water contamination is not generally a risk until the point where the water tolerance of the penetrant is met.
• Dirt and insoluble solids
  Dirt and insoluble solid contamination can result from poor cleaning or allowing contaminant materials to fall into the tank.
• Organic material
  Oils, lubricants, paints, greases, organic solvents, cleaning solvents and degreasing fluid are all sources of organic material contamination. Whilst penetrants are able to absorb amounts of oils and solvents, their level of fluorescence will be decreased and the penetrant washability will also be affected.
• Alkaline cleaners and acids
  Alkaline cleaners and acids represent the most serious type of contamination as they destroy fluorescence when they come into contact with a penetrant. In addition, some alkaline cleaners contain metasilicates, which can prevent penetrants from entering and therefore detecting a crack.

Causes of penetrant degradation include:

• Heat
  In some cases heat can be used to speed up the action of a penetrant. However, prolonged exposure to temperatures over 60 °C can reduce the fluorescence of a penetrant. Temperatures in excess of 120 °C will destroy fluorescence completely.
• Evaporation
  Penetrants stored in open tanks will undergo continuous evaporation, especially if the tanks are large and exposed to warmer temperatures. Evaporation may cause an increase in viscosity, which would subsequently increase the time taken to remove the penetrant.
• Faulty equipment
  Un-calibrated or faulty equipment and accessories can compromise penetrant systems. For example, drying oven thermostats or controls that are set improperly set can lead to incorrect oven temperatures. Similarly water pressure gauges can malfunction or the UV output from black light bulbs can be reduced with aged bulbs.

The effects of contamination and degradation will depend on the type and amount present. Any change in colour or consistency should be addressed immediately to ensure consistent inspection results.

Penetrant system testing can be performed in-house or using an external service. ASTM E1417 has established standards for performance checks for in-use materials.

Facilities that do not have the instrumentation or resources to carry out on-site testing can opt to use the Magnaflux PeneCert Service.

1. Get a quote: Contact us for a price quotation for your PeneCert service.
    
2. Collect samples: For each in-use material to be tested, collect at least 500ml sample.
    
3. Label bottle(s): Fill out a label and attach to the appropriate sample bottle(s). Please ensure that each bottle cap is tightened securely.
    
4. Complete form: Fill out a PeneCert menu form, indicating the testing that you require. If you are sending more than one sample of penetrant, please complete one form per sample.
    
5. Send samples: Send your samples to: Aerotech Laboratories Ltd, (Magnaflux PeneCert), Unit 20, Mercia Business Village, Westwood Business Park, Coventry, CV4 8HX, UK.
    
6. Results: We will email you the test results as soon as they are available.
    
7. Invoice: Invoices will be issued from the Magnaflux office in Swindon, UK.