Better late than never 😂

Answer to "I have a couple questions. What is the scale of the cracks shown? (I assume the the medium enlarges the scale of the cracks) and why are the magnetic field lines perpendicular to the electromagnets? It is my understanding that magnetic field lines propagate outward from what is normal to the surface of the magnet": You can estimate the length of the cracks based on the approximate length of the test specimen (approx. 200 mm). Unfortunately, you cannot measure the width or depth of the cracks. As regards the magnetic field lines, the entire experimental setup is not shown. The electromagnets are outside the video window, but this is a more complex issue.

Answer to "What method is used to demagnetize the ferromagnetic material after the magnetic particle inspection?" By using an alternating magnetic field in the machine, that is not switched off abruptly, but slowly (let us say within a second). The remaining magnetism is very low in the end.

Answer to "Is there any risk of getting electric shock while pouring the ferrite suspension on the workpiece while current is flowing through it?": No, there is no risk. Although the electric current is very high in this case (around 1000 to 2000 Ampere), the voltage is very low, around 5 to 10 Volts.

Call Illinois Tool Works to find a dealer.

Answer to "There have been no new tests/videos in a few years, did you run out of material to destroy? Your videos explain a lot that I have read or heard about over the years. Make some more videos please. Idiots are making videos on KZfaq, your videos are an antidote for those.": Thanks for the praise and the encouragement. New videos concerning classical materials science will probably be started within a year or two. The problem is the effort to produce them - and my current work in materials research.

I appreciate that you taking the time to reply. Thanks.

Answer to "is the tail stock electrically connected to the earth?": The metal cases around some of its parts are connected to the earth. The electric poles for the workpiece are not connected to the earth, but fully insulated. This prevents accidental shortcuts towards the metallic parts of the machine. The voltage between the poles is very low, just a few volts.

Answer to "What may be the maximum possible dimension of specimen that can be inspected using Magnetic Particle Testing?": The dimensions of the specimen are not limited, so you can also test extremely large specimens. However, you do not bring the specimen to the testing machine, but do it the other way around: You bring a comparatively compact mobile testing equipment to the specimen.

Answer to "I just started doing this at my job. Still fairly new to it. How would i know the difference between a legit deep crack and one that is more of a surface defect? Not sure if you guys will understand what im trying to say lol": This one of the problems of MPI, the depth of a crack cannot be measured reasonably.

Answer to "Hello i saw there it shown both vertical and longitudinal defect . My question does ure machine can produce 2 type curent flow and magnetic/coil flow in 1 shot so u can found 2 direction of those defect? Thks from Indonesia": We have only used one magnetisation direction at a time in the video. Nevertheless, you can often see defects that extend almost in the direction of the magnetic field, because in most cases the magnetic field does not run exactly along the defects and therefore has a component perpendicular to the defects. A trick to show all defects is to use both types of magnetisation in quick succession.

thank you in advance

The particles they use to show the crack and inspect it , only go onto the defect and never on the rest of the part because of a magnetic leakage and the particles will only run to the magnetic leak

mohd mahmood hussain what are you talking about??

+WingedBull1 job joiner

Class does not give certification. After that you need, I think, 210 hourS for level I and 640 for level II. The reason is the powers that be in ASNT figure that in those hours you will have seen enough to do that level job. I've got about 22,000 hours and would occasionally see something new - and rejectionable - in gas turbine blades.

Answer to "Could you manually turn the test piece 90 degrees instead of switching the machine to current-flow mode? Would that accomplish the same thing?" Yes absolutely. Sometimes it is easier to rotate the specimen by 90 degrees (which in our case would have been an option), sometimes it is more practical to use the current flow method (for example, for long cylindrical specimens or tubes).

@@MaterialsScience2000 Ok, that really helps me clarify things. Thank you for your reply!

John Lopez Why?

mag particle is a shortened version.. it's called magnetic particle.

Lol it’s the Same thing .

Answer to "what is that fluid that she pours on that metal?": The fluid is a suspension of - magnetic particles (often particles of pure iron), - a fluorescent dye and - a wetting agent (dish-washing liquid for example) in water.

Answer to "are there any fire hazards associated with this technique": No, mainly because no combustible materials are required.

Answer to "Why these cracks are visible in UV rays ?": A UV fluorescent agent was added to the test suspension. The UV fluorescent agent covers the magnetic particles and fluoresces brightly under UV light.

What does she need protecting from?

The heavy 🪨 axx bar or the kerosene that fxxxing eats flesh or her stank axx breath or your stank axx breath

Answer to "How much current used for MPI" In the current flow method we typically apply about 1000 to 2000 amps for our comparatively large specimens.

Answer to "I don't see crystal clear how the longitudinal magnetization is achieved. The circular mag is seen because the test piece is in contact with poles. I used to see long. mag using coils. Thanks in advance.": The magnetization in longitudinal direction was achieved by two electromagnets, one on the left side of the sample, and one on the right side, causing the magnetic field to flow in longitudinal direction >> from the left magnet >> through the specimen and then >> to the right magnet.

SergeantTubesocks The one that I used at my last job was taking off a Navy ship from the sixties, don't feel bad!!