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

1. Presented by
Md. Arman Hossain
SAJ Industrial & Inspection Company

2. Introduction of DPT
 Dye penetrant inspection (DPI), also called liquid penetrate
inspection (LPI) or penetrant testing (PT), is a widely applied and
low-cost inspection method for all non-porous materials (metals,
plastics, or ceramics)

3. What is DPT
Liquid penetrant testing is a method that is used to reveal
surface breaking flaws by bleed-out of a colored or
fluorescent dye from the flaw.

4. History of DPT
 The oil and whiting method used in the railroad industry
in the early 1900s was the first recognized use of the
principles of penetrants to detect cracks. The oil and
whiting method used an oil solvent for cleaning followed
by the application of a whiting or chalk coating, which
absorbed oil from the cracks revealing their locations. Soon
a dye was added to the liquid. By the 1940s, fluorescent or
visible dye was added to the oil used to penetrate test
objects

5. Advantage of DPT
 Sensitive to small surface discontinuities
 Can inspect metal and non-metal
 Works on complex geometric shapes
 Visual, real-world results
 portable
 Liquid penetrant testing materials are individually very affordable
 Its relatively easy to use

6. Disadvantage or Lamination of DPT
 Only sensitive to surface-breaking defects
 Surface must be clean properly
 Can not inspect porous meter metal generally
 No depth sizing
 User dependent
 Some rubber and plastics may be affected by penetrant material

7. Porous metal
Porous metal is a metal which has large volume of pore or voids.

8. Application metal of DPT

9. Usage material in DPT
1. Cleaner
2. Penetrant
3. Developer
4. Black light for fluorescent method
Cleaner : is a remover .it is use to clean the test surface or
remove the surface from oil,dust,rust and other contaminant.

10. Penetrant
penetrant means which have penetrate ability .dye penetrant penetrate into
discontinuity of specimen by capillary action. which produces contrasting
indications against the white developer background
Capillary action is the ability of a liquid to flow in narrow spaces without the
assistance.it occur cause of adhesion and cohesion.

11. Vcn

12. Classification of penetrant
Penetrant are three types –
1.Visible dye penetrant
2.Fluorescent dye penetrant
3.Duel sensitivity penetrant
Each types of penetrant is again classified into tree groups
according to their removal process.
1.Sovlent removal penetrant
2.Water washable penetrant
3.Post emulsifiable penetrant

13. Visible penetrant
This types of penetrant visible in normal light and
containing visible colour. normally red colour.

14. Fluorescent penetrant
Fluorescent penetrant : this types of penetrant is colourless and
not visible in normal light. require ultraviolet or black light to
visible the penetrant.

15. Duel sensitivity penetrant:
this types of penetrant combines of visible penetrant
and fluorescent penetrant . indication can be visible
under normal light also black light.

16. Water washable penetrant
Water washable penetrant is Remove by water . It is in-built in emulsifier
and easily washable in water.
Suitable for rough surface or thread .Poor reliability for wide and shallow
discontinuity

17. Solvent removable penetrant
This type of penetrant is remove by solvent.
Main advantage of this type of penetrant is portability and
excellent for checking a large part remote area

18. Post Emulsifiable penetrant
Emulsifier apply on this type of penetrant .emulsifier react
with penetrant and make it water washable . then apply water
to remove penetrant.

19. Emulsifier
Emulsifier is a one type of detergent agent . which react with penetrant
and make penetrant water washable.
There are two types of emulsifier , that are-
1.lipophilic-oil based detergent
2.hydrophilic-water based detergent

20. Developer
Developer is highly absorbent, the penetrant is drawn out
from the discontinuity by it blotting action .
The developer are basically are two types
1. Dry developer
2. Wet developer-wet developer are two types
a) aqueous developer-
I. Water suspension type
II. Water soluble type
a) Non-aqueous developer

21. Dry developer
Dry developers are white, fluffy high absorbent powders that can be
applied to a thoroughly dry surface.
It’s usually used on fluorescent penetrant.

22. Aqueous wet developer
this types of developer is water based developer .
Water suspension :a suspension of absorptive white powder suspend in water ,
water soluble : a water –soluble absorptive white powder in water .
the water suspension type developer requires agitation during use . the water
soluble developer need not require agitation.
Water soluble type water suspension type

23. Non-aqueous developer
Non-aqueous developer is a suspension of absorptive white powder in
solvent . prior to application requires agitation.

24. black light
black light is the ultraviolet light . which supply the light of wavelength
365 nm . the ultraviolet light wavelength is below the visible light
wavelength.
The intensity of black light should be minimum 1000mw/cm2

25. Classification of DPT
 Depend on portability
1. Portable dye penetrant testing
2. Stationary dye penetrant testing
Portable DPT Stationary DPT

26. Dye penetrant testing naturally are classified according to the penetrant
medium .
Depend on the penetrant medium dye penetrant testing are
1. Visible dye penetrant testing
2. Fluorescent dye penetrant testing
3. Dual sensitivity dye penetrant testing
Each system classified into 3 method according to remove process-
1. Water washable dye penetrant testing
2. Solvent removable dye penetrant testing
3. Post emulsifiable dye penetrant testing

27. Principle of DPT
penetrant to be drawn into a "clean" surface breaking flaw by capillary
action. After dwell time excess surface penetrant is removed and
developer applied. It draw out the penetrant from the flaw by blotter
action.

28. During DPT inspection ,we have to follow some step .this step are-
1. Pre –cleaning of the test part
2. Application of penetrant and wait for dwell time
3. Removal of excess penetrant from test surface
4. Apply developer
5. Inspection and evaluation of indication
6. Post clean

29. Pre-clean
Apply penetrant
remove
Apply
developer
Post clean
Fig : Flow chart for Visible and Fluorescent Dye Penetrant Testing
alkaline steam
Apply water washable penetrant
Solvent washVapor degrease
Paint stripperMechanical wash detergentUltrasonic wash
Water wash Water washSolvent wipe-off
dry
Apply removerApply emulsifier
Dry
Apply solvent removable penetrant Apply post emulsifiable penetrant
Aqueous developer
Developer(dry or
non-aqueous
Dry
Developer(dry or
non-aqueous)
inspect
DetergentWater rinse
Dry
Mechanical wash
Dry
Vapour degrease Solvent soak Ultrasonic clean
Dry

30. step water washable dye solvent removable dye post emulsifiable dye
penetrant system penetrant system penetrant system
pre clean apply solvent or others apply solvent or others apply solvent or others
Apply penetrant and apply water washable dye apply solvent removable dye apply post emulsifiable dye
wait for dwell time. Penetrant Penetrant Penetrant
apply emulsifier or remover
Remove excess apply water apply solvent remover apply water
Penetrant
Dry aqueous Dry aqueous
Developer Developer
Apply Developer
Dry or non- Dry apply dry or non-aqueous developer Dry or non- Dry
aqueous dev. aqueous dev.
Inspection inspection Inspection inspection
Post cleaning apply solvent remover or other Apply solvent remover or other apply solvent remover or other

31. Indication in DPT
Penetrant indication are classified into three group
1.True indication-true indication presence cause of true discontinuity of
the part.
2.Irrelevant indication- this type of indication is not form due to true
discontinuity of the part
3.False indication- it also not form due to true discontinuity.

32. True indication
Linear indication Round indication

33. Irrelevant indication
cv
Arc strike
Mechanical damage
spatter

34. Sometimes it is necessary to record the indication for use in the report
and inspection record for future reference, this recording can be
accomplished by any other following -
Photography-
Recording or indication

35. sketch
fbb

36. Thanks
to
everybody