dye penetrant inspection

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We offer type II visible penetrant inspection.  This can be performed to a specific inspection procedure or inspection standard where requested. It can be used to detect cracks and surface breaking defects.  Its suitable for castings, forgings and weldments.  Typical inspection standards that we commonly work to are BS EN ISO 3452-1, ASME V Article 6 and ASTM E165. Surface crack detection using dye penetrant inspection is a cost effective method. Its very useful on non-ferrous metals where MPI cannot be utilized. It works on a principle of capillary action where this phenomena pulls fluids into tight narrow spaces  such as crack faces. The dye is normally visible red or UV fluorescent yellow

We offer higher sensitivity type I fluorescent penetrant inspection which is available at different sensitivity levels.  This can be performed to a specific inspection procedure or inspection standard where requested. It can be used to detect very fine cracks and even stress corrosion cracking as per the photo of the in-service end ring above.  Dye penetrant inspection works on the principle of capillary action where this phenomena pulls fluids into tight narrow spaces  such as crack faces. The dye is normally type II visible red or type I UV fluorescent yellow.  Fluorescent penetrant inspection is best suited to final machined components where the surface finish is high quality and a high sensitivity inspection is required.

In-Service Cracking

Dye penetrant inspection can be used on non-porous resin cast components and non-porous composite components.  Its used to detect surface breaking defects on composite materials like surface cracks and surface fiber failures.  The photo above shows cracking around a stud bolt hole on a resin & fiber composite cast component used in the power generation component. Typical components tested are stator cooling water boxes, radial pin insulation sleeves and polymer matrix composite braid.

We use our  dye penetrant inspection station for most machine shop batch components and small one-offs. We can perform both type I & type II dye penetrant inspections. We have lots of experience testing machine shop components, we will respect your machined components and protect them from damage whilst they are in our care. Typical components are non-ferrous valve seats, valve spindles, stud bolts, cap nuts, radial pins, gears, pinions and most final machined non-ferrous components. We can work to many different international  inspection standards or inspection procedures.

Dye penetrant inspection is a useful NDT method when used in conjunction with ultrasonics to aid the inspection of the bonded metal interfaces that are present on white metal bearings, thrust pads, hydrogen seals or weld cladding/buttering runs. Dye penetrant inspection will clearly reveal the location of any unbonded edges.

Dye penetrant inspection can be performed on electro-plated surfaces to detect surface breaking defects and cracking within the electro-plated layer.