Pump Supply & Repair Group can employ several different methods of Non Destructive Testing (NDT). What can NDT be used on:
- Pressure Vessels
- Shafts
- Storage Tanks
- Pipework
- Boilers
- Welds
- Heat Exchangers
- Turbines
- Castings & Forgings
- Pump Casings
Ultra-Sonic Testing
Our engineers can use Ultrasonic Testing to identify cracks and determine a material’s thickness. The test can detect flaws in welds and castings, and also in wrought items such as rolled plate and forgings. We can use ultrasonic NDT on all types of equipment, including compressor bodies, high pressure pipework and for weld inspection.
Dye Penetrant Inspection (DPI)
Dye Penetrant Inspection is used to detect surface breaking cracks in materials which are not visible to the naked eye. This method can be used on both ferrous and non ferrous materials. Our site personnel would thoroughly clean the substrate to remove any grease or dirt, and then liberally apply the brightly coloured ‘penetrant’ and leaves the penetrant for 10 – 20 minutes to soak into the substrate. At this point, excess penetrant is removed with a fine water spray and a lint free cloth, and then the ‘developer’ is applied. The role of the developer is to draw the penetrant from the surface defects out onto the surface, forming bleed-outs. The technicinan then inspects the substrate with a light source and marks all of the locations of cracks. DPI is used to detect flaws in welds, hairline cracks, surface porosity, and fatigue cracks.
Magnetic Particle Inspection (MPI)
MPI is a process of detecting surface and just below surface flaws in ferroelectric metals (such as iron, nickel, cobalt, and some alloys). The process works by magnetising the metal being tested. Pump Supply & Repair Group utilises the Non Direct magnetisation method as this doesn’t involve passing an electric current through the metal. Once magnetised, the presence of a discontinuity (flaw) on or near the surface will allow magnetic flux to leak into the air. The technician applies a spray which has ferrous iron particles suspended in it. These particles will build up in the area of flux leakage, creating an indication of discontinuation. The technician will note all areas of ‘indications’ and then clean the liquid off, and inspect and evaluate those areas further to determine what action needs to be taken to rectify the areas where flaws are present in the material.
Hardness Testing
A way of identifying what material a component is made from (for example a steel shaft) is to test its Indentation Hardness. Our engineers can use a Rebound Type Portable Hardness Tester to determine the hardness of the metal. From then referring to data tables, the material composition can be determined. This ensures that the wrong material is not mistakenly used.
For more information on NDT, or to discuss the NDT services we offer, please call our Operations Director, Martin Cooper on 0161 864 4678, or email him at mcooper@pumpgroup.co.uk
