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Comparison between A106-B, A672-C70/Cl.22, A53-B and API 5L-B

March 5, 2002

Thomas J.C. Eun

Pipe Materials

Materials A106-B A672-C70/Cl22 A53-B API 5L-B

Subject Seamless carbon steel pipe

for high-temperature service

Electric-fusion-welded (EFW)

steel pipe for high-pressure

service at moderate

temperatures

Pipe, steel, black and hot-

dipped, zinc-coated, welded

and seamless

Seamless and welded line

pipes

1. SCOPE • This specification covers

seamless carbon steel pipe

for high-temperature

(Consideration should be

given to possible

graphitization of the material

at the high temperatures at

which it may be used.)

• NPS ⅛ to NPS 48

inclusive, with nominal wall

thickness as given in ASME

B36.10.

� Fabricated from pressure-

vessel quality plate

� Heat treatment may or may not

be required to attain the

desired properties or to comply

with applicable code

requirements.

� The specification nominally

covers NPS 16 (405mm) in

outside diameter or larger with

wall thickness up to 3 in. (75

mm), inclusive.

� NPS ⅛ to NPS 26 inclusive � It covers seamless and weld

steel line pipe.

� The purpose of this

specification is to provide

standards for pipe suitable for

use in conveying gas, water,

and oil in both oil and natural

gas industries.

2. Applied

Temperature

-29 to 427℃ -49 to 427℃ -29 to 427℃ -29 to 427℃

3. Referenced

Documents

ASTM A520 specification for

supplementary requirements

for seamless and electric-

resistance-welded carbon steel

tubular products for high-

temperature service

conforming to ISO

recommendations for boiler

construction.

ASTM A516-60 specification for

pressure vessel plates, carbon

steel, for moderate-and lower-

temperature service

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Pipe Materials

Materials A106-B A672-C70/Cl22 A53-B API 5L-B

Subject Seamless carbon steel pipe

for high-temperature service

Electric-fusion-welded (EFW)

steel pipe for high-pressure

service at moderate

temperatures

Pipe, steel, black and hot-

dipped, zinc-coated, welded

and seamless

Seamless and welded line

pipes

4. Process � Made by killed steel

� Pipe NPS 1½ and under

may be either hot finished or

cold drawn

Unless otherwise specified,

pipe NPS 2 and over shall be

furnished hot finished.

� Made by killed steel and fine

grain practice

� The joints shall be double

welded, full penetration welds.

� RT : Full

Types and Grades;

� Type F: Furnace butt welded

(EFW), continuous welded

Grade A

� Type E ; Electric-resistance

welded (ERW), Grades A and B

– UT & MT to be done for NPS

2 and larger

� Type S; Seamless, Grade A

and B

Types;

EFW, ERW, and Seamless

5. Heat

Treatment

� Hot-finished pipe need not

be heat treated.

� Cold-drawn pipe shall be

heat treated after the final

cold draw pass at a

temperature of 1200℉(650℃) or higher.

� Not required normalizing

� Base Metal: As rolled (for 40

mm thickness and under),

normalized, and stress relieved

� Products: Class 22 shall be

uniformly heated within the

post-weld heat-treatment

temperature range indicated in

Table 2 for a minimum of 1

h/in. of thickness or 1 h,

whichever is greater.

� The weld seam of ERW pipe in

grade B shall be heat treated

after welding to min. of

1,000°F(540°C).

Pipe furnished to this

specification may be as-rolled,

normalized, normalized and

tempered, sub-critically stress

relieved, or sub-critically age

hardened.

6. Mechanical Properties

Ts, min psi

(MPa)

60,000 (415) 70,000-90,000 (485-620) 60,000 (415)

60,000 (415)

Ys, min psi

(MPa)

35,000(240) 38,000 (260) 35,000 (240)

35,000 (240)

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Pipe Materials

Materials A106-B A672-C70/Cl22 A53-B API 5L-B

Subject Seamless carbon steel pipe

for high-temperature service

Electric-fusion-welded (EFW)

steel pipe for high-pressure

service at moderate

temperatures

Pipe, steel, black and hot-

dipped, zinc-coated, welded

and seamless

Seamless and welded line

pipes

7. Chemical Composition, product analysis

Seamless ERW Seamless ERW

C, maxA 0.30 0.27~0.31 as per thickness 0.30 0.30 0.27 0.26

Mn 0.29 ~ 1.06 0.79~1.30 as per thickness 1.20 max 1.20 max 1.15 max 1.15 max

P, max 0.035 0.035 0.050 0.050 0.030 0.030

S, max 0.035 0.035 0.045 0.045 0.030 0.030

Si, min 0.10 0.13~0.45

Cr, maxB 0.40 0.40

Cu, maxB 0.40 0.40

Mo, max 0.15 0.15

Ni, maxB 0.40 0.40

V, maxB 0.08

These five

elements

combined shall

not exceed1%.

0.08

Notes A

; For each reduction of 0.01%

below the specified carbon

max., an increase of 0.06% Mn

above the specified max, will

be permitted up to a max. of

1.35%.

Cb, V, Ti, or combinations

thereof, may be used by

agreement between purchaser

and manufacturer.

8. Results

Remark &

Notes by

Thomas Eun

Even if it is for high

temperature, it can be

extended its using range due to

improving the toughness by

grain refinement, austenitic

size five and over.

It will be additionally required the

grain refinement, austenitic size

five and over to improve the

toughness.

� Sometimes, min. 0.1 % Si is additionally required in the

equipment/piping specifications of the purchaser. This silicon will

be helpful to keep killed condition more or less, not sufficient and

also to prevent to a certain extent the graphitization of the material

at the high temperatures and hydrogen attack/ SSC/ HIC.

� Normalizing is often required by the purchaser’s specifications.

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Pipe Materials

Materials A106-B A672-C70/Cl22 A53-B API 5L-B

Subject Seamless carbon steel pipe

for high-temperature service

Electric-fusion-welded (EFW)

steel pipe for high-pressure

service at moderate

temperatures

Pipe, steel, black and hot-

dipped, zinc-coated, welded

and seamless

Seamless and welded line

pipes

Results A106-B has excellent

properties in moderate and

high temperature service

because of hot finishing,

chemical composition and

additional requirements,

A672-C70/Cl.22 has excellent

properties for high- pressure

service at moderate temperature.

They are not in fully killed condition.

Conclusion for

Deviation From

30” Sch.10

SA672-C70/Cl.22

to API 5L-B

The main difference between both materials is Strength, De-oxygen Treatment (Killing), and NDE. Normally API 5L-B is not recommended

in Hydrocarbon Process area (including Suncor Standards) due to the quality and safety. Especially there are a lot of brittle failure cases for

non-impact tested and non-killed steels in low temperature environment (-40°F to 32°F).

I would like to agree the deviation only for utility and offsite lines but hydrocarbon process area.