NON DESTRUCTIVETESTING : NON DESTRUCTIVETESTING Prepaid by:- guided by:-
Pinkal patel(0104me061070) Pro :-M .K.Chopra
Dept. Of Mech. Engg. Slide 2: Prepaid by:- guided by:-
Pinkal patel(0104me061070) Pro :-M .K.Chopra
Dept. Of Mech. Engg. Outline : Outline Introduction to NDT
Overview of Six Most Common NDT Methods
Selected Applications Definition of NDT : Definition of NDT General name for all methods which permit testing / inspection of materials / parts without impairing its future usefulness.
Without rupturing the object, the analysis can be done by this method. Quality control can be achieved by this method. FLUORESCENT PENETRANT INDICATION Introduction : Introduction The use of noninvasive techniques to determine the integrity of a material, component or structure or quantitatively measure some characteristic of an object.
i.e. Inspect or measure without doing harm.
The basic use of this method is very useful when any of manufacturing process applied to produce object. This process gives very accurate result for any damage or defect. The defect should be of material or of the process, by which the object is being manufactured. We can use this method for several purposes as like inspection of vessels, air craft, etc., where very accurate dimensions are required. Types Of Defects : Types Of Defects inherent defects - present during initial production of raw materials
processing defects - resulted from the manufacturing process
service defects - occurred during the operation Examples of causes of defects : Examples of causes of defects Blowholes - gas trapped during
Segregation – during solidification of alloy
Scale - oxide formation on the surface of a metal heated to high temperature
Stress - residual stress after cold working or rapid cooling Methods of NDT : Methods of NDT Six Most Common NDT Methods:-
Other NDT Methods :-
Flux leakage Visual
X-ray Visual Inspection : Visual Inspection Most basic and common inspection method.
Tools include fiberscopes, borescopes, magnifying glasses and mirrors. Liquid Penetrate Inspection : Liquid Penetrate Inspection A liquid with high surface wetting characteristics is applied to the surface of the part and allowed time to seep into surface breaking defects.
The excess liquid is removed from the surface of the part.
A developer (powder) is applied to pull the trapped penetrant out the defect and spread it on the surface where it can be seen. Visual inspection is the final step in the process. Magnetic Particle Inspection : Magnetic Particle Inspection The part is magnetized. Finely milled iron particles coated with a dye pigment are then applied to the specimen. These particles are attracted to magnetic flux leakage fields and will cluster to form an indication directly over the discontinuity. This indication can be visually detected under proper lighting conditions. Ultrasonic Inspection : Ultrasonic Inspection High frequency sound waves are introduced into a material and they are reflected back from surfaces or flaws.
Reflected sound energy is displayed versus time, and inspector can visualize a cross section of the specimen showing the depth of features that reflect sound. Eddy Current Testing : Eddy Current Testing Eddy current testing is particularly well suited for detecting surface cracks but can also be used to make electrical conductivity and coating thickness measurements. Here a small surface probe is scanned over the part surface in an attempt to detect a crack. Radiography : Radiography The radiation used in radiography testing is a higher energy (shorter wavelength) version of the electromagnetic waves we see as visible light. The radiation can come from an X-ray generator or a radioactive source. What are Some Uses of NDE Methods? : What are Some Uses of NDE Methods? Flaw Detection and Evaluation
Structure and Microstructure Characterization
Estimation of Mechanical and Physical Properties
Stress (Strain) and Dynamic Response Measurements
Material Sorting and Chemical Composition Determination When are NDE Methods Used? : When are NDE Methods Used? There are NDE applications at almost any stage
In the production or life cycle of a component.
To assist in product development.
To screen or sort incoming materials.
To monitor, improve or control manufacturing processes.
To verify proper processing such as heat Treating.
To verify proper assembly.
To inspect for in-service damage. Common Application of NDT : Common Application of NDT Inspection of Raw Products
Inspection Following Secondary Processing
In-Services Damage Inspection Inspection For In-Service Damage : Inspection For In-Service Damage Cracking
Heat Damage , etc. Different Inspection Carried-out : Different Inspection Carried-out Power Plant Inspection
Wire Rope Inspection
Storage Tank Inspection
Jet Engine Inspection
Pressure Vessel Inspection
Pipeline Inspection For More Information on NDT : For More Information on NDT The Collaboration for NDT Education
The American Society for Nondestructive Testing