July 8, 2021: Pharmaceutical Interview Questions and Answers

1. What is the composition of SS 304, SS 304L, SS 316, and SS 316L?

Following are the composition of SS 304, SS 304L, SS 316, and SS 316L

2. What is the meaning of Suffix L in SS 316L and SS 304L?

Suffix L for SS 316 and SS 304 represents low carbon content. Standard grade consists of ≤ 0.08 % carbon and low carbon grade consists of ≤ 0.03 % carbon content.

3. What are the different types of stainless steel in terms of material composition?

4. What is Hastelloy?

Hastelloy is a nickel-molybdenum-chromium superalloy with an addition of tungsten designed to have excellent corrosion resistance in a wide range of severe environments. The high nickel and molybdenum contents make the nickel steel alloy especially resistant to pitting and crevice corrosion in reducing environments while chromium conveys resistance to oxidizing media. The low carbon content minimizes carbide precipitation during welding to maintain corrosion resistance in as-welded structures. This nickel alloy is resistant to the formation of grain boundary precipitates in the weld heat-affected zone, thus making it suitable for most chemical process application in an as welded condition.

Source: megamex.com

5. In what applications is Hastelloy used?

i. Pharmaceutical and food processing equipment
ii. Chemical processing components like heat exchangers, reaction vessels, evaporators, and transfer piping
iii. Sour gas wells
iv. Waste treatment