Failure to perform quality control inspections introduces the potential for inherent discontinuities to become defects. Non-destructive testing (NDT) is a method that detects the presence of defects or flaws in a part or component without damaging or destroying the material being examined. Here, Vikas Panchal offers a basic NDT for flaw detection in industrial pumps and valves.

 

Industrial pumps and valves contain assemblies with several rotating and stationary components, manufactured by casting, forging, rolling and welding, with subsequent heat treatment and manufacturing procedures. The American Society for Nondestructive Testing (ASNT) has defined NDT as “the process that consists of the inspection, testing or evaluation of materials, components and assemblies for material's discontinuities, properties and machine problems without further damaging or destroying the part's serviceability”

 

Non-destructive Evaluation (NDE) is a method often used interchangeably with non-destructive testing. However, technically, NDE is usually utilized to describe examinations that are more quantitative in nature. For example, an NDE exam would not only locate a defect, but it would also be used to measure its size, shape, and orientation, as well as its influence on the remaining life of structures and components. NDE may be also utilized to determine material properties such as fracture toughness, shapeability and other physical characteristics.

 

NDT is a very broad and interdisciplinary field that plays a crucial role in assuring structural components and systems function in a reliable, cost-effective manner. 

 

NDT utilizes varied test methods to detect and orientate flaws and characterize material conditions that could lead to industrial pumps and valve failures. These tests are performed in a manner that does not affect the future usage, such as applicability of the object. Because NDT allows parts and materials to be inspected and measured without damaging them, it provides an excellent balance between quality control and cost-effectiveness.

 

Pump system components that are usually subjected to NDT include pressure containment castings such as casings, covers, nozzle heads, impellers, shafts, bearing housings and other critical parts. Similarly, valve bodies are subjected to NDT. NDT does not take place of the need for hydrostatic testing of pressure containment parts of pumps and valves, but it supplements the pressure testing.