This is a presentation i often use to introduce particle colliders to university students.
64-yogini with their 64-bhairava
Full description
Full description
Issue 64-65
Descripción completa
Full description
mitsubishi
TEMA 64 INGLÉS
Issue 64-65Description complète
Particle Reinforce Composite
CONTENT PART 1 • Overview Test Methods • Basis of test methods • Execution of of ex examina inatio tions • Detec tectab table typ type of of ffaaults • Limits of of ap application
CONTENT PART 2 • Planning of NDT • Conten tent of of te test pr procedures • Evaluation of of re results • Reco Record rdin ingg of of tes tests ts and and res resul ults ts • Applicable NDT Rules
Magnetic Particle Testing (MT) • Principle: • Mate Materi rial alss mus mustt be be ferr ferrom omag agne netiticc • Str Stray ay flux flux of of a magn magneti eticc field field gener generate atess line liness of of force, which emerge from the surface when passing a discontinuity • Discon Discontin tinuit uitie iess will will be be visib visible le by accu accumu mulat latio ionn of ferromagnetic ferromagnetic particles
Generation of a Flux Indication
Test Methods
Contrast Test surface and mag. particles together Test should provide high contrast.Appropriate particle colours should be chosen, e.g. black, red, grey. With fluorescent particles, max. fluorescence brightness should be selected. Remark: Thin surface coating (background paint “white”) together with black mag. Particles provide very good contrast. poor contrast Strong background disturbance
Distribution of Field Lines in the Material
Magnetic Field Types Alternating Current:
•
Penetration depth 2-3 mm from surface
•
Small influence of surface shape
•
Required magnetic force is smaller (lower weight of equipment
•
Scope of application:
•
Welds, gear-tooth
•
Magnetic Field Types
Direct current:
•
Deeper penetration
•
Insufficient magnetisation at cross section changes, edges
•
Scope of application:
•
Stationary equipment
•
Depth Penetration of Magnetic Fields Surface flaw
A.C magnetic field skin-effect, penetration small. Flaw depth max. 2-3 mm with f=50 hZ
Subsurface flaws
D.C Magnetic field entire cross section magnetized, greater depth penetration. Flaw depth max.5-8 mm
Standard Magnetic Particle Testing Yoke Magnetization
Yoke Magnetisation
a:
Soft iron core
b:
Magnetic field lines
c:
Magnetic coil
d:
Flux indication
e:
Stray flux
f:
Defect
Magnetisation Direction
Standard Equipment
Application of Cross Yoke Magnet
MT of a circumferential weld.
Right – Hand - Rule
I=
Current
H = Magnetic Field Streng (magnetic field lines) B = Magnetic Induction
The right hand rule define the relation between curent, magnetic induction and the direction of the magnetic field lines.
Direct Fluxing
Application of Direct Fluxing
Magnetisation by prods
Application of Direct Fluxing
Coil Magnetisation
Application of Coil Magnetisation
Threading Bar Technique
Induction Fluxing
Testing Accessories • Indication capability of the testing fluid • Defect recognition • Suspension evaluation • After a setting time of 30 minutes the required concentration must be obtained.
Test Block MTUC – No.3
• To check magnetic powder suspensions for their efficiency • Regular control
Berthold Test Block • For determination of the field direction • Minimum angle between field – and crack direction 30o
Field Strength Meter • Determination of field strength • 20 to 65 A/cm or (2,0 to 6,5 kA/m) • Control of demagnetisation • Maximum allowable residual field intensity • Max. 4A/cm (0,4 kA/m)
Light Intensity Meter UV Intensity Meter
Luxmeter
Detectable Flaw Sizes
Defects Indication Surface flaws
Subsurface defects
Irrelevant Indications Development of stray-flux with strong magnetization
Cross-section changes, edges
Irrelevant Indications
Local Permeability Change
MT of 2,5% Ni-Steel, austenitic welded, rechecked by PT
Evaluation of Discontinuities
Form of indication (linear, round)
Size of indications
Quantity of indications
Location, direction and Orientation of indications
Magnetic Particle Standards • Standards for performance of tests: • DIN EN 1290 “Magnetic Particle Examination of Welds” • ASME Sec. V, Subsection A, Article 7 “Magnetic Particle Examination” • ASME E-709 “Standard Recommended Practice for Magnetic Particle Examination” • DGZfP Richtline EMO “Performance of magnetic particle examinations” (EN ISO 9934-1)
Evaluation Standards • AD-Merkblatt HP 5/3 Anlage 1 “Non Destructive testing of welded connections” (Pressure vessels) • DIN-EN 1291 “Magnetic Particle Examination of Welds – Evaluation Criteria” • Germanischer Lloyd II/3 Chapter 2 Sec.4 “Non Destructive testing of welds”
Acceptance Criteria
mperfections in Welded Joints in Steel ccording to EN 25817
