» Non-Destructive Testing » Liquid Penetrant Testing

Liquid Penetrant Testing

         The penetrant method of non-destructive testing is based on capillary penetration of indicator liquid (penetrant) into the surface defects (cracks, pores, etc.). After intermediate cleaning and subsequent drying, a developer is applied as a thin, white layer onto the surface to be inspected. The developer “pulls” the penetrant out of the surface defects and makes them visible as coloured, linear or rounded indications. Documentation is possible by means of adhesive films, photographs or video techniques.

       Penetrant testing is reliable in detecting the defects with a width down to the range of μm. Penetrant inspection can detect surface defects accurately and independent of types, materials and surface configuration of the objects to be tested. Other methods of non-destructive testing can be applied with restrictions only. Inevitable condition: defects must be open to surface. Capillary systems have been also used for the leak testing.

Lichide penetrante Lichide penetrante Lichide penetrante Lichide penetrante
Cleaning Penetrant Application Intermediary Cleaning Developer application, surface
inspection, documentation

            The liquid penetrant testing method can detect surface defects accurately and easily, regardless of the type, materials and surface configuration of the objects to be tested.
           Other non-destructive examination methods may be applied only with restrictions. Necessary condition: the defects must be related to the surface.
The set of products for examination with penetrating liquids is a combination of the following materials: degreasing, penetrating and developing.

Depending on the mode of examination, the penetrating liquids can be:

             Color contrast penetrant liquids, for which the interpretation of the examination results is performed in daylight;
             Fluorescent penetrant liquids, for which the interpretation is carried out using lamps with ultraviolet light;
             "Double purpose" penetrant liquids, where the interpretation can be performed both in daylight and in the light of the ultraviolet lamp.

The removal of the excedd pentetrant can be made with:

Type A Water
Type B
Lipophilic Emulsifier
Oil Based Emulsifier
Tip C Solvent (liquid)
Tip D Hydrophilic Emulsifier
Opţional preclătire (apă)
Emulgator (diluat în apă)
Clătire finală (apă)
Tip E Apă şi solvent

The used developer can be:

Type a dry
Type b Water Soluble
Type c Aqueous Suspension
Type d Solvent Based
Tip e Water or solvent based for special applications

          Our company is the exclusive representative in Romania of the German HELLING GmbH. Our partner produces penetrant liquids for all the mentioned processes, and we deliver - usually promptly from our warehouse - the most common products requested by our customers.
In the following, we present the requested products in Romania. For other products, please contact us for further information.