Objective 04: Metal Specifications Flashcards Preview

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Flashcards in Objective 04: Metal Specifications Deck (20)
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Who determines which metals may be used to construct pressure vessels, pressure piping, and process piping systems?



From whom does ASME adopt material specifications?



After development of ASME codes, who approves them?



When can an unidentified metal be used in a plant application?



Who determines material specification and selection in plant application?

Design Engineer


Why should materials only be ordered from reputable suppliers?

To avoid counterfeit products that are inferior


What are the 6 categories of metals?

1. Low Carbon Steel (carbon content <0.30%)
2. Medium Carbon Steel (carbon content 0.30-0.60%)
3. High Carbon Steel (carbon content 0.60-1.5%)
4. Cast Iron (carbon content 2-6%)
5. Alloy Steels
6. Non-Ferrous Metals


What are Non-Ferrous Metals in use?

1. Copper
2. Aluminum
3. Brass
4. Nickel
5. Tungsten
6. Zirconium


What metal is most piping in a power plant made of?

Low carbon or alloy steel


How is metal chosen for a particular job?

Based on safety and metal survivability to ensure the metal can withstand the most extreme environment it will be used in and still retain a factor of safety.


What does an engineering piping schedule call for?

ASTM "A" or "B" number material of specified grade, dimension, and schedule


ASTM "A" Material

Carbon Steels and Alloys


ASTM "B" Material

Non-Ferrous Metals


Material Test Reports (MTRs)/Certificates of Testing

Comprehensive chemical and physical analysis of the metal used to manufacture the pipe or fitting that are made available by the vendor to the puchaser upon request


Where do MTRs originate?

The smelter where the metal was made


Heat Number

Identification number for each batch of metal (or alloy) and all the products made from that batch that follows products made from these materials throughout their lieftime, including being copied unto lengths of pipe cut from the original length


What information do MTRs contain?

1. Pipe or Fitting Identification
2. Heat Number of the metal
3. Chemical Composition
4. ASME or ASTM Specification Number
5. Grade
6. Schedule
7. Tensile Strength
8. Yield Point of Metal
9. Results of Specialized Testing, e.g. Charpy Test
10. Any Heat Treatment Process the part underwent


What is the process by which ASME specifies which metals may be used to construct pressure vessels, pressure piping, and process piping systems?

1. ASME adopts material specifications developed by ASTM
2. ASME lists the reviewed and approved materials in the ASME BPVC
3. ASME codes are approved by ANSI


For whom are the extensive complexity of ASME codes regarding material specifications intended?

Professional engineers who design power and processing plants


Why should power engineers be familiar with basic metal specifications?

May have to monitor the suitability of the materials used. The chief power engineer may be responsible for purchasing piping, fittings, and equipment to replace or repair plant systems.