LT of NDT Technology - A Conventional, Versatile and Cost-Effective Testing Mode

NDT or nondestructive testing is safe and also cost-effective. Due to these reasons they are being used by different industries in a rapid manner. Particularly, manufacturing industries are actually taking it up on themselves to use NDT technology in Malaysia and other countries. These can be divided into traditional and non-traditional ones and both these are still very much in vogue. There are several techniques used for detecting flaws in metallic components. One such method is the Liquid Penetrant testing or LT. This method is employed to detect flaws like cracks on the surface of any kind of non-porous material like plastics, ceramics and metals.

More about Liquid Testing

Liquid Penetrant Testing is also referred to as Dye Penetrant Testing or Penetrant Inspection method. This particular method is used in the industrial sector by people who are experienced and qualified to conduct such tests. This is particularly very effective in detecting cracks in pipelines of course made from various metals and machine components. Detecting and rectifying those cracks can help in avoiding accidents and preventing failures. Different kinds of defects can be detected using this process and it includes fatigue cracks, hairline cracks and porosity. Some more industries being served with Dye Penetrant testing include aerospace, petrochemical, engineering and automotive companies.

Although it is a widely used nondestructive testing technique, it is still considered to be the least technologically sound testing method compared to others like ultrasonic testing and radiography. There are reasons to believe this. It is definitely a cost-effective, versatile and easy to perform test which requires relatively less trained technicians to be completed. The process of work for LT is quite simple but a little lengthy.

The Process of Liquid Penetrant Testing

The process of LT continues in the following manner:

• The material to be tested needs to be cleaned using a spray cleaner that is easily wiped off with a cloth. Wire brushing and grinding might be required.
• A Dye Penetrant is applied to the surface with the help of aerosol spray.
• The liquid is left on the surface for sometime so that the liquid penetrates into the cracks and fissures making them visible to the technicians.
• After this process is done and the cracks are visible, you have to remove the liquid with a cloth.
• The developer then acts to draw out the excess liquid that may have seeped into a crack making it highly visible and providing an indication of the defects on the surface of the object.

LT of NDT Technology in Malaysia depends on only visual inspection thus making it a little weaker method than others. The color indication is important and hence many technicians prefer using fluorescent dye. This is a conventional technique. However, its versatility is a big point why it is so popular. This is quite easy to manipulate through the cracks and thus is a viable nondestructive technique to be used. It still continues to be the preferred technique of many.