NDT LIQUID PENETRANT TESTING

NDT LIQUID PENETRANT TESTING – QUESTIONS

1.Which of the following liquid penetrants would require the shortest penetrant dwell time?

1. One with low viscosity
2. One with high viscosity
3. One with a medium viscosity
4. Viscosity has no effect on dwell time

2.Which of the following emuslifiers will diffuse into oil based penetrants at the fastest rate?

1. One with a viscosity of 100 centistokes
2. One with a viscosity of 30 centistokes
3. One with a viscosity of 60 centistokes
4. Viscosity does not affect diffusion rate

3.Aluminium comparatpr blocks which are used for comparison tests are re cracked at which of the following temperatures after initial use?

1. 900 degrees farenheit
2. 800 degrees celsius
3. 900 degrees celsius
4. 800 degress farenheit

4.What is the benefit of using visible dye penetrant over a fluorescent penetrant?

1. It is easier to remove the excess background
2. Greater sensitivity is obtained
3. No special lighting is required
4. All the above are benefits

5.Flash point relates to which of the following?

1. Temperature at which vapour spontaneously ignites
2. Temperature at which liquid spontaneously ignites
3. Temperature at which a liquid ignites in the presence of a small flame
4. Temperature at which the vapours given off from a liquid ignite in the presence of a small flame

6.Which of the following is also known as a self -emulsifiable penetrant?

1. Solvent removable
2. Water washable
3. Post emulsifiable
4. Oil based penetrant

7.The ‘Cleveland open cup test’ is a test for which of the following?

1. Specific Gravity
2. Viscosity
3. Chemical inertness
4. Flash point

8.Which of the following is considered to be the most sensitive developer when used with a fluorescent post emulsifiable penetrant?

1. Dry Powder
2. Aqueous soluble
3. Non aqueous wet
4. Aqueous suspnedible

9.For what purpose is a refractometer used in liquid pentrant inspection?

1. Checking specific gravity of lipophilic emulsifier
2. Checking sensitivity of water soluble wet developer
3. Checking concentration of hyrdrophilic remover
4. Checking particle enisty of dry powder

10.Water will at some time contaminate liquid penetrant but hopefully with oil based penetrant this water will not mix and fall to the bottom of the tank. For this to occur how does the specific gravity of pentrant compare to that of water?

1. It normally has a specific gravity more than one
2. It normally has a specific gravity more than water
3. It normally has a specific gravity less than one
4. Specific gravity has nothing to do with density

 Answer:

1. One with low viscosity
2. One with a viscosity of 30 centistokes
3. 800 degress farenheit
4. No special lighting is required
5. Temperature at which the vapours given off from a liquid ignite in the presence of a small flame
6. Water washable
7. Flash point
8. Non aqueous wet
9. Checking concentration of hyrdrophilic remover
10. It normally has a specific gravity less than one