This presentation Based on Non Destructive Testing.the Abbreviation is NDT.Dye penetrant Testing (DPT) is the part of NDT .I think my presentation will be helpful for NDT Related person
This presentation is intended to provide an introduction to the NDT method of penetrant testing. Penetrant Testing (PT) is a non destructive testing method that builds on the principle of Visual Inspection.
Liquid penetrant inspection is one of the oldest and most widely used non destructive testing methods. It is also called as dye penetrant inspection.Penetrant testing can be applied to most of materials including metallic and non metallic objects.This Presentation will gives you an overview about Liquid Penetrant Testing and Various methods used for Inspection
This presentation Based on Non Destructive Testing.the Abbreviation is NDT.Dye penetrant Testing (DPT) is the part of NDT .I think my presentation will be helpful for NDT Related person
This presentation is intended to provide an introduction to the NDT method of penetrant testing. Penetrant Testing (PT) is a non destructive testing method that builds on the principle of Visual Inspection.
Liquid penetrant inspection is one of the oldest and most widely used non destructive testing methods. It is also called as dye penetrant inspection.Penetrant testing can be applied to most of materials including metallic and non metallic objects.This Presentation will gives you an overview about Liquid Penetrant Testing and Various methods used for Inspection
Non-Destructive Testing is a simple way of testing without destroying.Techshore Inspection Services, with a humble beginning in Cochin, India started as an Engineering, Procurement and Construction company offering wide range of innovative services and engineering solutions in the field of Oil and Gas, Power and other major industries in the disciplines of Mechanical, Civil, Instrumentation and NDT, soon expanded its business into professional training in all the aforesaid disciplines.
Non-Destructive Testing is a simple way of testing without destroying.Techshore Inspection Services, with a humble beginning in Cochin, India started as an Engineering, Procurement and Construction company offering wide range of innovative services and engineering solutions in the field of Oil and Gas, Power and other major industries in the disciplines of Mechanical, Civil, Instrumentation and NDT, soon expanded its business into professional training in all the aforesaid disciplines.
This presentation gives an information about: photoelasticity, covering syllabus of Unit-3, of Experimental stress analysis subject for BE course under Visvesvaraya Technological University (VTU), Belgaum.
This presentation gives the information about:electrical resistance strain gauges, covering syllabus of Unit-1, Sub: Experimental stress analysis for BE course.
This presentation gives the information about introduction to control systems
Subject: Control Engineering as per VTU Syllabus of Aeronautical Engineering.
Notes Compiled By: Hareesha N Gowda, Assistant Professor, DSCE, Bengaluru-78.
Disclaimer:
The contents used in this presentation are taken from the text books mentioned in the references. I do not hold any copyrights for the contents. It has been prepared to use in the class lectures, not for commercial purpose.
Non-destructive testing or non-destructive testing (NDT) is a wide group of analysis techniques used in science and technology industry to evaluate the properties of a material, component or system without causing damage.
"This ppt also includes some notes in the slide so to see notes go to the view options and select notes page."
Liquid Penetrant Testing - Principles, types and properties of liquid penetrants, developers, advantages and limitations of various methods, Testing Procedure, Interpretation of results. Magnetic Particle Testing- Theory of magnetism, inspection materials Magnetisation methods, Interpretation and evaluation of test indications, Principles and methods of demagnetization, Residual magnetism
This template was created for DSCE, Aeronautical students. You have to replace the institution details.
Create a separate document for each chapter, so that under numbering, you can change the sequence of chapter main heading according to chapter wise. i.e., 2.1, 2.2 etc.
Same procedure is applicable to Figure caption and Table caption.
This template can be used to generate, BE seminar report, M.Tech and Ph.D thesis also.
This template is created to assist UG students in generating their thesis without much hassle.
Contents are taken from VTU website. I don’t hold any copyright for this document.
Hareesha N G
Assistant Professor
DSCE, Bengaluru
This document is an Instruction manual for Computer aided machine drawing
Subject: Computer aided machine drawing (CAMD)
Syllabus contest is as per VTU, Belagavi, India.
Notes Compiled By: Hareesha N Gowda, Assistant Professor, DSCE, Bengaluru-78.
This document gives the class notes of Unit-8: Torsion of circular shafts and elastic stability of columns. Subject: Mechanics of materials.
Syllabus contest is as per VTU, Belagavi, India.
Notes Compiled By: Hareesha N Gowda, Assistant Professor, DSCE, Bengaluru-78.
This document gives the class notes of Unit-8: Torsion of circular shafts and elastic stability of columns. Subject: Mechanics of materials.
Syllabus contest is as per VTU, Belagavi, India.
Notes Compiled By: Hareesha N Gowda, Assistant Professor, DSCE, Bengaluru-78.
This document gives the class notes of Unit 6: Bending and shear Stresses in beams. Subject: Mechanics of materials.
Syllabus contest is as per VTU, Belagavi, India.
Notes Compiled By: Hareesha N Gowda, Assistant Professor, DSCE, Bengaluru-78.
This document gives the class notes of Unit 5 shear force and bending moment in beams. Subject: Mechanics of materials.
Syllabus contest is as per VTU, Belagavi, India.
Notes Compiled By: Hareesha N Gowda, Assistant Professor, DSCE, Bengaluru-78.
This document gives the class notes of Unit 3 Compound stresses. Subject: Mechanics of materials.
Syllabus contest is as per VTU, Belagavi, India.
Notes Compiled By: Hareesha N Gowda, Assistant Professor, DSCE, Bengaluru-78.
This document gives the class notes of Unit 2 stresses in composite sections. Subject: Mechanics of materials.
Syllabus contest is as per VTU, Belagavi, India.
Notes Compiled By: Hareesha N Gowda, Assistant Professor, DSCE, Bengaluru-78.
This document contains: Mechanics of Materials: Question bank from old VTU Question papers ; Pprepared by Hareesha N G, DSCE, Bengaluru. These questions are picked from last 06 years of old VTU question papers.
This presentation was prepared for a seminar. I have shared this with you. This is not related to curriculam. Please writre your criticisms to: hareeshang@gmail.com.
This presentation gives the information about Screw thread measurements and Gear measurement of the subject: Mechanical measurement and Metrology (10ME32/42) of VTU Syllabus covering unit-4.
This presentation gives the information about Force, Pressure and Torque measurements of the subject: Mechanical measurement and Metrology (10ME32/42) of VTU Syllabus covering unit-6.
This presentation gives the information about mechanical measurements and measurement systems of the subject: Mechanical measurement and Metrology (10ME32/42) of VTU Syllabus covering unit-5.
This CIM and automation laboratory manual covers the G-Codes and M-codes for CNC Turning and Milling operations. Some concepts of Robot programming are also introduced.
Literature Review Basics and Understanding Reference Management.pptxDr Ramhari Poudyal
Three-day training on academic research focuses on analytical tools at United Technical College, supported by the University Grant Commission, Nepal. 24-26 May 2024
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
An Approach to Detecting Writing Styles Based on Clustering Techniquesambekarshweta25
An Approach to Detecting Writing Styles Based on Clustering Techniques
Authors:
-Devkinandan Jagtap
-Shweta Ambekar
-Harshit Singh
-Nakul Sharma (Assistant Professor)
Institution:
VIIT Pune, India
Abstract:
This paper proposes a system to differentiate between human-generated and AI-generated texts using stylometric analysis. The system analyzes text files and classifies writing styles by employing various clustering algorithms, such as k-means, k-means++, hierarchical, and DBSCAN. The effectiveness of these algorithms is measured using silhouette scores. The system successfully identifies distinct writing styles within documents, demonstrating its potential for plagiarism detection.
Introduction:
Stylometry, the study of linguistic and structural features in texts, is used for tasks like plagiarism detection, genre separation, and author verification. This paper leverages stylometric analysis to identify different writing styles and improve plagiarism detection methods.
Methodology:
The system includes data collection, preprocessing, feature extraction, dimensional reduction, machine learning models for clustering, and performance comparison using silhouette scores. Feature extraction focuses on lexical features, vocabulary richness, and readability scores. The study uses a small dataset of texts from various authors and employs algorithms like k-means, k-means++, hierarchical clustering, and DBSCAN for clustering.
Results:
Experiments show that the system effectively identifies writing styles, with silhouette scores indicating reasonable to strong clustering when k=2. As the number of clusters increases, the silhouette scores decrease, indicating a drop in accuracy. K-means and k-means++ perform similarly, while hierarchical clustering is less optimized.
Conclusion and Future Work:
The system works well for distinguishing writing styles with two clusters but becomes less accurate as the number of clusters increases. Future research could focus on adding more parameters and optimizing the methodology to improve accuracy with higher cluster values. This system can enhance existing plagiarism detection tools, especially in academic settings.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
Water billing management system project report.pdfKamal Acharya
Our project entitled “Water Billing Management System” aims is to generate Water bill with all the charges and penalty. Manual system that is employed is extremely laborious and quite inadequate. It only makes the process more difficult and hard.
The aim of our project is to develop a system that is meant to partially computerize the work performed in the Water Board like generating monthly Water bill, record of consuming unit of water, store record of the customer and previous unpaid record.
We used HTML/PHP as front end and MYSQL as back end for developing our project. HTML is primarily a visual design environment. We can create a android application by designing the form and that make up the user interface. Adding android application code to the form and the objects such as buttons and text boxes on them and adding any required support code in additional modular.
MySQL is free open source database that facilitates the effective management of the databases by connecting them to the software. It is a stable ,reliable and the powerful solution with the advanced features and advantages which are as follows: Data Security.MySQL is free open source database that facilitates the effective management of the databases by connecting them to the software.
We have compiled the most important slides from each speaker's presentation. This year’s compilation, available for free, captures the key insights and contributions shared during the DfMAy 2024 conference.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
Harnessing WebAssembly for Real-time Stateless Streaming PipelinesChristina Lin
Traditionally, dealing with real-time data pipelines has involved significant overhead, even for straightforward tasks like data transformation or masking. However, in this talk, we’ll venture into the dynamic realm of WebAssembly (WASM) and discover how it can revolutionize the creation of stateless streaming pipelines within a Kafka (Redpanda) broker. These pipelines are adept at managing low-latency, high-data-volume scenarios.
KuberTENes Birthday Bash Guadalajara - K8sGPT first impressionsVictor Morales
K8sGPT is a tool that analyzes and diagnoses Kubernetes clusters. This presentation was used to share the requirements and dependencies to deploy K8sGPT in a local environment.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
NUMERICAL SIMULATIONS OF HEAT AND MASS TRANSFER IN CONDENSING HEAT EXCHANGERS...ssuser7dcef0
Power plants release a large amount of water vapor into the
atmosphere through the stack. The flue gas can be a potential
source for obtaining much needed cooling water for a power
plant. If a power plant could recover and reuse a portion of this
moisture, it could reduce its total cooling water intake
requirement. One of the most practical way to recover water
from flue gas is to use a condensing heat exchanger. The power
plant could also recover latent heat due to condensation as well
as sensible heat due to lowering the flue gas exit temperature.
Additionally, harmful acids released from the stack can be
reduced in a condensing heat exchanger by acid condensation. reduced in a condensing heat exchanger by acid condensation.
Condensation of vapors in flue gas is a complicated
phenomenon since heat and mass transfer of water vapor and
various acids simultaneously occur in the presence of noncondensable
gases such as nitrogen and oxygen. Design of a
condenser depends on the knowledge and understanding of the
heat and mass transfer processes. A computer program for
numerical simulations of water (H2O) and sulfuric acid (H2SO4)
condensation in a flue gas condensing heat exchanger was
developed using MATLAB. Governing equations based on
mass and energy balances for the system were derived to
predict variables such as flue gas exit temperature, cooling
water outlet temperature, mole fraction and condensation rates
of water and sulfuric acid vapors. The equations were solved
using an iterative solution technique with calculations of heat
and mass transfer coefficients and physical properties.
2. Liquid penetrant inspection is a method that is used to
reveal surface breaking flaws by bleed out of a colored
or fluorescent dye from the flaw.
The technique is based on the ability of a liquid to be
drawn into a "clean" surface breaking flaw by capillary
action.
After a period of time called the "dwell," excess
surface penetrant is removed and a developer applied.It
draws the penetrant from the flaw to reveal its presence.
Colored (contrast) penetrants require good white light
while fluorescent penetrants need to be used in darkened
conditions with an ultraviolet "black light".
LIQUID PENETRANT INSPECTION
Hareesha N G, Dept of Aero Engg, DSCE 2
3. BASIC PROCESSING STEPS OF A LIQUID
PENETRANT INSPECTION
One of the most critical steps of a liquid penetrant
inspection is the surface preparation.
The surface must be free of oil, grease, water, or
other contaminants that may prevent penetrant
from entering flaws.
The sample may also require etching if mechanical
operations such as machining, sanding, or grit
blasting have been performed.
These and other mechanical operations can smear
metal over the flaw opening and prevent the
penetrant from entering.
1. Surface Preparation
Hareesha N G, Dept of Aero Engg, DSCE 3
4. Once the surface has been thoroughly cleaned and
dried, the penetrant material is applied by
spraying, brushing, or immersing the part in a
penetrant bath.
2. Penetrant Application:
Hareesha N G, Dept of Aero Engg, DSCE 4
5. 1. The penetrant is left on the surface for a
sufficient time to allow as much penetrant as
possible to be drawn from or to seep into a
defect.
2. Penetrant dwell time is the total time that the
penetrant is in contact with the part surface.
3. Dwell times are usually recommended by the
penetrant producers or required by the
specification being followed.
3.Penetrant Dwell:
Hareesha N G, Dept of Aero Engg, DSCE 5
6. 4) The times vary depending on the application,
penetrant materials used, the material, the
form of the material being inspected, and the
type of defect being inspected for.
5. Minimum dwell times typically range from
five to 60 minutes. Generally, there is no
harm in using a longer penetrant dwell time
as long as the penetrant is not allowed to dry.
6. The ideal dwell time is often determined by
experimentation and may be very specific to
a particular application.
3.Penetrant Dwell:
Hareesha N G, Dept of Aero Engg, DSCE 6
7. 4.Excess Penetrant Removal:
This is the most delicate part
of the inspection procedure
because the excess penetrant
must be removed from the
surface of the sample while
removing as little penetrant as
possible from defects.
Depending on the penetrant system used,
this step may involve cleaning with a
solvent, direct rinsing with water, or first
treating the part with an emulsifier and
then rinsing with water.Hareesha N G, Dept of Aero Engg, DSCE 7
8. 1. Liquid penetrant inspection (LPI) is one of the most widely
used nondestructive evaluation (NDE) methods.
2. Its popularity can be attributed to two main factors: its
relative ease of use and its flexibility.
3. LPI can be used to inspect almost any material provided that
its surface is not extremely rough or porous.
4. Materials that are commonly inspected using LPI include the
following:
Metals (aluminum, copper, steel, titanium, etc.)
Glass
Many ceramic materials
Rubber
Plastics
Common Uses of Liquid Penetrant Inspection
Hareesha N G, Dept of Aero Engg, DSCE 8
9. 1) The method has high sensitivity to small surface
discontinuities.
2) The method has few material limitations, i.e. metallic and
nonmetallic, magnetic and nonmagnetic, and conductive
and nonconductive materials may be inspected.
3) Large areas and large volumes of parts/materials can be
inspected rapidly and at low cost.
4) Parts with complex geometric shapes are routinely
inspected.
5) Indications are produced directly on the surface of the
part and constitute a visual representation of the flaw.
6) Aerosol spray cans make penetrant materials very
portable.
7) Penetrant materials and associated equipment are
Primary Advantages
Hareesha N G, Dept of Aero Engg, DSCE 9
10. 1) Only surface breaking defects can be detected.
2) Only materials with a relatively nonporous surface can
be inspected.
3) Precleaning is critical since contaminants can mask
defects.
4) Metal smearing from machining, grinding, and grit or
vapor blasting must be removed prior to LPI.
5) The inspector must have direct access to the surface
being inspected.
6) Surface finish and roughness can affect inspection
sensitivity.
7) Multiple process operations must be performed and
controlled.
8) Post cleaning of acceptable parts or materials is required.
Primary Disadvantages
Hareesha N G, Dept of Aero Engg, DSCE 10
11. Introduction
• This module is intended to provide an introduction to
the NDT method of penetrant testing.
• Penetrant Testing, or PT, is a nondestructive
testing method that builds on the principle
of Visual Inspection.
• PT increases the
“seeability” of small
discontinuities that
the human eye might
not be able to detect
alone.
Hareesha N G, Dept of Aero Engg, DSCE 11
12. How Does PT Work?
•In penetrant testing, a liquid with high surface wetting
characteristics is applied to the surface of a component
under test.
•The penetrant “penetrates” into surface breaking
discontinuities via capillary action and other mechanisms.
•Excess penetrant is removed from the surface and a
developer is applied to
pull trapped penetrant back
the surface.
•With good inspection
technique, visual
indications of any
discontinuities present
become apparent.
Hareesha N G, Dept of Aero Engg, DSCE 12
13. What Makes PT Work?
•Every step of the penetrant process
is done to promote capillary action.
•This is the phenomenon of a liquid
rising or climbing when confined to
small openings due to surface
wetting properties of the liquid.
•Some examples:
– Plants and trees draw water up from the
ground to their branches and leaves to
supply their nourishment.
– The human body has miles of capillaries
that carry life sustaining blood to our
entire body.
Hareesha N G, Dept of Aero Engg, DSCE 13
14. Basic Process of PT
1) Clean & Dry Component 4) Apply Developer
2) Apply Penetrant
3) Remove Excess
5) Visual Inspection
6) Post Clean Component
Hareesha N G, Dept of Aero Engg, DSCE 14
15. What Can Be Inspected Via PT?
Almost any
material that has
a relatively
smooth, non-
porous surface
on which
discontinuities or
defects are
suspected.
Hareesha N G, Dept of Aero Engg, DSCE 15
16. What Can NOT be Inspected Via PT?
•Components with rough
surfaces, such as sand castings,
that trap and hold penetrant.
•Porous ceramics
•Wood and other fibrous
materials.
•Plastic parts that absorb or
react with the penetrant
materials.
•Components with coatings that
prevent penetrants from
entering defects.
Defect indications
become less
distinguishable as
the background
“noise” level
increases.
Hareesha N G, Dept of Aero Engg, DSCE 16
17. What Types of Discontinuities Can
Be Detected Via PT?
All defects that are open to
the surface.
– Rolled products-- cracks,
seams, laminations.
– Castings--cold shuts, hot tears,
porosity, blow holes,
shrinkage.
– Forgings– cracks, laps, external
bursts.
– Welds– cracks, porosity,
undercut, overlap, lack of
fusion, lack of penetration.
Hareesha N G, Dept of Aero Engg, DSCE 17
18. Choices of Penetrant Materials
Penetrant Type
I Fluorescent
II Visible
Method
A Water Washable
B Postemulsifiable - Lipophilic
C Solvent Removable
D Postemulsifiable - Hydrophilic
Developer Form
Dry Powder
Wet, Water Soluble
Wet, Water Suspendable
Wet, Non-Aqueous
Hareesha N G, Dept of Aero Engg, DSCE 18
19. Penetrant Materials
Penetrants are formulated to possess a number of
important characteristics. To perform well, a
penetrant must:
– Spread easily over the surface being inspected.
– Be drawn into surface breaking defects by capillary action
or other mechanisms.
– Remain in the defect but remove easily from the surface of
the part.
– Remain fluid through the drying and developing steps so it
can be drawn back to the surface.
– Be highly visible or fluoresce brightly to produce easy to see
indications.
– Not be harmful to the inspector or to the material being
tested.
Hareesha N G, Dept of Aero Engg, DSCE 19
20. Sensitivity Levels
• Penetrants are also formulated to produce a variety of
sensitivity levels. The higher the sensitivity level, the
smaller the defect that the penetrant system is capable of
detecting.
• The five sensitivity levels are:
– Level 4 - Ultra-High Sensitivity
– Level 3 - High Sensitivity
– Level 2 - Medium Sensitivity
– Level 1 - Low Sensitivity
• As the sensitivity level increases, so does the number of
non relevant indications. Therefore, a penetrant needs to
be selected that will find the defects of interest but not
produce too many non relevant indications.
Hareesha N G, Dept of Aero Engg, DSCE 20
21. Visible Vs Fluorescent PT
• Inspection can be performed
using visible (or red dye) or
fluorescent penetrant
materials.
• Visible Pt is performed under
white light while fluorescent
PT must be performed using
an ultraviolet light in a
darkened area. All are all in
the level 1 sensitivity range.
• Fluorescent PT is more
sensitive than visible PT
because the eye is more
sensitive to a bright
indication on a dark
background. Sensitivity
ranges from 1 to 4.
Photo Courtesy of Contesco
Hareesha N G, Dept of Aero Engg, DSCE 21
22. Penetrant Removal Method
Penetrants are also classified by the method of
removing the excess penetrant.
•Solvent Removable penetrants are removed by
wiping with a cloth dampened with solvent. They are
supplied in aerosol cans for portability and are primarily
used for spot checks.
•Water Washable penetrants are removed with a
course spray of water. They are the easiest to employ
and most cost effective when inspecting large areas.
•Post-Emulsifiable penetrants are water-washable
only after they have reacted with an emulsifier solution.
A post-emulsifiable system is used when washing the
penetrant out of the defect is a concern. The emulsifier
is given time to reacts with the penetrant on the surface
but not the penetrant trapped in the flaw.
Hareesha N G, Dept of Aero Engg, DSCE 23
23. Developers
•The role of the developer is to pull trapped
penetrant out of defects and to spread it
out on the surface so that it can be seen.
Also provides a light background to
increase contrast when visible penetrant is used.
•Developer materials are available in several different forms
– Dry Powder is a mix of light fluffy powder that clumps together where penetrant
bleeds back to the surface to produces very defined indications.
– Wet, Water Suspendable is a powder that is suspended in a water that covers the
surface with a relatively uniform layer of developer when the water is evaporated. The
solution is somewhat difficult to maintain as the powder settles out over time.
– Wet, Water Soluble is a crystalline powder that forms a clear solution when mixed
with water. The solution recrystallizes on the surface when the water is driven off.
Indications sometimes lack definition and look milky. Not recommended for use with
water-washable penetrants.
– Wet, Non-Aqueous - is supplied in a spray can and is the most sensitive developer
for inspecting small areas. It is too costly and difficult to apply to large areas.
Hareesha N G, Dept of Aero Engg, DSCE 24
25. Pre-cleaning – Step 1
Pre-cleaning is the most
important step in the PT
process!!!
•Parts must be free of dirt,
rust, scale, oil, grease, etc.
to perform a reliable
inspection.
•The cleaning process must
remove contaminants from
the surfaces of the part
and defects, and must not
plug any of the defects.
Hareesha N G, Dept of Aero Engg, DSCE 26
26. Caution About Metal Smearing
Some machining, surface finishing and cleaning
operations can cause a thin layer of metal to
smear on the surface and prevent penetrant from
entering any flaws that may be present.
Etching of the surface prior to inspection is
sometimes required.
Before Sanding
After Sanding
After Etching
Hareesha N G, Dept of Aero Engg, DSCE 27
27. Penetrant Application – Step 2
Many methods
of application
are possible
such as:
– Brushing
– Spraying
– Dipping/
Immersing
– Flow-on
– And more
Hareesha N G, Dept of Aero Engg, DSCE 28
28. Dwell Time
•The penetrant solution must
be allowed to “dwell” on the
surface of the part to allow
the penetrant time to fill any
defects present.
•The dwell time vary
according to penetrant type,
temperature, material type
and surface finish.
Hareesha N G, Dept of Aero Engg, DSCE 29
29. Excess Penetrant Removal – Step 3
The removal technique depends upon the
type of penetrant used, as stated earlier…
– Solvent Removable
– Water Washable
– Post Emulsifiable
Hareesha N G, Dept of Aero Engg, DSCE 30
30. Excess Penetrant Removal – Step 3 (cont.)
Water Washable
•A coarse water spray is
used to remove the excess
penetrant.
•The procedure used as a
guideline for the
inspection will specify
water temperature
(typically 50-100°F) and
pressure (typically not
more than 40 psi), etc.
Hareesha N G, Dept of Aero Engg, DSCE 31
31. Excess Penetrant Removal – Step 3 (cont.)
Solvent Removable
•The part is wiped with a
clean dry cloth to remove
the bulk of the excess
penetrant.
•Then, a cloth lightly
dampened with solvent is
used to remove any
remaining penetrant on
the surface.
Hareesha N G, Dept of Aero Engg, DSCE 32
32. Solvent Removable (cont.)
Any time a solvent is
used in the penetrant inspection
process, a
suitable flash time is
required to allow excess solvent to
evaporate.
Excess Penetrant Removal – Step 3 (cont.)
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33. Excess Penetrant Removal – Step 3 (cont.)
Post Emulsifiable
•When there is concern about removing much of the penetrant
from the defect, a post emulsifiable system is used.
•This involves an additional step
in which an emulsifier is applied
to the surface of the part after
the penetrant dwell time.
•The emulsifier is given just
enough time to react with
the penetrant on the surface
to render it water washable
but not enough time to diffuse
into the penetrant trapped in
the defects.
Hareesha N G, Dept of Aero Engg, DSCE 34
34. Developer Application – Step 4
The method of developer application is is
dependent on the type of developer used. The
primary methods for the following main developer
types will be covered in the following slides.
– Dry
– Wet
– Nonaqueous Wet
Hareesha N G, Dept of Aero Engg, DSCE 35
35. Developer Application – Step 4 (cont.)
Dry Powder Developer
•Prior to applying a dry
powder developer, the
component must be
thoroughly dried. Drying is
usually accomplished in a hot
air circulating oven.
•The developer is then applied
by immersing the part in the
powder or by dusting of the
part with the powder.
•The part can also be placed in
a developer dust cloud
chamber.
Hareesha N G, Dept of Aero Engg, DSCE 36
36. Developer Application – Step 4 (cont.)
•Wet developers are applied by
immersing or spraying the part
while it is still wet from the
penetrant removal process.
•The part is completely coated and
the excess liquid allowed to drain
to prevent pooling
•The part is then dried in a hot air
circulating oven.
Wet Developer (water- suspended
and water- soluble)
Hareesha N G, Dept of Aero Engg, DSCE 37
37. Developer Application – Step 4 (cont.)
Nonaqueous Developer (AKA
Solvent-Suspended)
•Nonaqueous developer is
applied by a aerosol spray to a
thoroughly dried and cooled
part.
•A thin even coating should be
applied. The coating should be
white but still slightly
transparent when performing a
visible dye penetrant
inspection, and even thinner
when performing a fluorescent
penetrant inspection.
Hareesha N G, Dept of Aero Engg, DSCE 38
38. Inspection/Evaluation – Step 5
In this step the inspector
evaluates the penetrant
indications against specified
accept/reject criteria and
attempts to determine the
origin of the indication.
The indications are judged
to be either relevant, non-
relevant or false.
Non-relevant weld geometry indications
Relevant crack indications from an
abusive drilling process
Hareesha N G, Dept of Aero Engg, DSCE 39
39. Inspection/Evaluation – Step 5
A very important step of
evaluation is to
document findings on
an inspection report
form or other record
keeping form.
This may be supported
with drawings or photos
of indications, etc.
Hareesha N G, Dept of Aero Engg, DSCE 40
40. Post Clean – Step 6
The final step in the penetrant
inspection process is to
thoroughly clean the part that
has been tested to remove all
penetrant processing
materials.
The residual materials could
possibly affect the
performance of the part or
affect its visual appeal.
Hareesha N G, Dept of Aero Engg, DSCE 41
41. Penetrant Inspection Systems
Penetrant systems can be highly portable or
stationary.
Portable Penetrant System Stationary Penetrant System
Image courtesy of Nebraska Army National Guard
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42. Verification of Penetrant System
Performance
Since penetrant testing
involves multiple processing
steps, the performance of the
materials and the processes
should be routinely checked
using performance verification
tools, which include:
– TAM Panels
– Crack Sensitivity Panels
– Run Check Panels
Hareesha N G, Dept of Aero Engg, DSCE 43
43. Advantages of Penetrant Testing
• Relative ease of use.
• Can be used on a wide range of material types.
• Large areas or large volumes of parts/materials can be
inspected rapidly and at low cost.
• Parts with complex geometries are routinely
inspected.
• Indications are produced directly on surface of the
part providing a visual image of the discontinuity.
• Initial equipment investment is low.
• Aerosol spray cans can make equipment very
portable.
Hareesha N G, Dept of Aero Engg, DSCE 44
44. Limitations of Penetrant Testing
• Only detects surface breaking defects.
• Requires relatively smooth nonporous material.
• Precleaning is critical. Contaminants can mask
defects.
• Requires multiple operations under controlled
conditions.
• Chemical handling precautions necessary (toxicity,
fire, waste).
• Metal smearing from machining, grinding and other
operations inhibits detection. Materials may need to
be etched prior to inspection.
• Post cleaning is necessary to remove chemicals.
Hareesha N G, Dept of Aero Engg, DSCE 45
45. Summary
•Penetrant testing (PT) is one of the most widely
used nondestructive testing methods.
•Its popularity can be attributed to two main factors,
which are its relative ease of use and its flexibility.
•However, PT involves a number of processing steps
that must be closely control to achieve optimal
sensitivity.
Hareesha N G, Dept of Aero Engg, DSCE 46
46. Glossary of Terms
•Capillary Action - the tendency of certain liquids
to travel or climb when exposed to small
openings.
•Contrast - the relative amount of light emitted or
reflected between and indication and its
background.
•Defect - a discontinuity that effects the usefulness
of a part or specimen.
•Developer - a finely divided material applied over
the surface of a part to help promote reverse
capillary action and thus bring out a penetrant
indication.
Hareesha N G, Dept of Aero Engg, DSCE 47
47. Glossary of Terms
•Discontinuity - any interruption in the normal
physical structure of a part or weld. It may or
may not affect the usefulness of a part.
•Dwell Time - the period of time that a penetrant
or developer must remain in contact with the
surface of a part under test.
•Emulsification Time - the time allowed for the
emulsifier to render the penetrant water
washable and thus allow the part to be washed.
•Emulsifier - a material applied over a film of
penetrant that renders it water washable.
Hareesha N G, Dept of Aero Engg, DSCE 48
48. Glossary of Terms
•Evaluation - the process of deciding as to the
severity of the condition after an indication has
been interpreted.
•False Indication - an indication caused by
improper processing; not caused by a relevant or
non-relevant condition.
•Flash Time - the time required for the solvent to
evaporate from the surface of a part when used
to preclean or remove excess penetrant.
•Fluorescent Dye - a dye which becomes
fluorescent (gives off light) when exposed to short
wave radiation such as ultraviolet light.
Hareesha N G, Dept of Aero Engg, DSCE 49
49. Glossary of Terms
•Indication - the visible evidence or penetrant
bleed-out on the surface of the specimen
•Interpretation - the process of evaluating an
indication in an attempt to determine the cause
and nature of the discontinuity.
•Non-Aqueous Developer - a developer in which
developing powder is applied as a suspension in a
quick drying solvent
•Penetrant - a liquid used in fluorescent or visible
dye penetrant inspection to penetrate into the
surface openings of parts inspected via these
methods
Hareesha N G, Dept of Aero Engg, DSCE 50
50. Glossary of Terms
•Relevant Indication - an indication that has been
determined not to be false or non-relevant - and
actual discontinuity
•Seeability - the characteristic of an indication that
enables it to be seen against the adverse conditions
of background, outside light, etc.
•Sensitivity - the ability of a penetrant to detect
surface openings. Higher sensitivity indicates
smaller discontinuities can be detected
•Ultraviolet Light (or Black Light) - light energy just
below the visible range of violet light (356
nanometers).
Hareesha N G, Dept of Aero Engg, DSCE 51
51. Glossary of Terms
•Viscosity - the resistance of a fluid to the motion
of its particles
•Washability - the property of a penetrant which
permits it to be cleaned from the surface of a part
by washing with water
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