Objective 04: Metal Specifications

Question 1

Who determines which metals may be used to construct pressure vessels, pressure piping, and process piping systems?

Answer 1

ASME

Question 2

From whom does ASME adopt material specifications?

Answer 2

ASTM

Question 3

After development of ASME codes, who approves them?

Answer 3

ANSI

Question 4

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

Answer 4

Never

Question 5

Who determines material specification and selection in plant application?

Answer 5

Design Engineer

Question 6

Why should materials only be ordered from reputable suppliers?

Answer 6

To avoid counterfeit products that are inferior

Question 7

What are the 6 categories of metals?

Answer 7

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

Question 8

What are Non-Ferrous Metals in use?

Answer 8

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

Question 9

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

Answer 9

Low carbon or alloy steel

Question 10

How is metal chosen for a particular job?

Answer 10

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.

Question 11

What does an engineering piping schedule call for?

Answer 11

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

Question 12

ASTM “A” Material

Answer 12

Carbon Steels and Alloys

Question 13

ASTM “B” Material

Answer 13

Non-Ferrous Metals

Question 14

Material Test Reports (MTRs)/Certificates of Testing

Answer 14

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

Question 15

Where do MTRs originate?

Answer 15

The smelter where the metal was made

Question 16

Heat Number

Answer 16

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

Question 17

What information do MTRs contain?

Answer 17

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

Question 18

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

Answer 18

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

Question 19

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

Answer 19

Professional engineers who design power and processing plants

Question 20

Why should power engineers be familiar with basic metal specifications?

Answer 20

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.