We all known what is PMI and the application industries of PMI.But how about the PMI testing methods?

There are three PMI testing methods.They are XRF Method,OES Method and LIBS Method.

XRF Method

XRF,namely X-ray Fluorescence Method is a PMI testing method to test the emitted secondary x-rays that are unique to the elements by exposing the material to a flux of x-rays released from the PMI gun. The XRF PMI gun would indicate the composition of the material by measuring this energy absorbed by the atoms of the material and intensity of the secondary x-rays.ASTM E 1476,a well-defined procedure,could guarantee reliable and accurate results. It can be used to analyze hot samples like process components at process or power plants. It could also analyze the component whether it is conductive or non-conductive; metallic or non-metallic, granular, or liquid forms.

XRF PMI testing method of ASTM A403 WP304 material pipe fittings

OES Method

OES,namely Optical Emission Spectrometry Method is a PMI testing method to examine the emitted light caused by the spark from the electrode in argon atmosphere. Because the spark could cause the material to emit light which has a unique coloration.It provides superior performance in measuring nitrogen, carbon, boron, and phosphorous in steel.

LIBS Method

LIBS,namely Laser-Induced Breakdown Spectroscopy method is the most advanced PMI testing methods so far, and it has made the greatest progress in recent years. With the continuous development of laser diodes, it is now possible to successfully launch small and strong laser beams onto the sample surface. The trace material on the surface of the object is dissipated by the laser.Then, a high-energy plasma composed of sample molecules is formed. When the plasma cools down, each element in the sample emits its characteristic wavelength, and then the wavelength of light is collected through the optical cable.This method is very fast with only one second and good at measuring aluminum alloys.So it is a useful method for sorting scrap metal.

XRF PMI testing method of ASTM A403 WP904L material pipe fittings

Haihao Group would choose the most appropriate PMI testing method for the different material piping products.And all the special materials need to pass PMI testing before shipped out.If you need the piping products with qualified material,contact Haihao Group freely.Email:sales@haihaogroup.com