ASTM A192,ASME SA192
Standard Specification for Seamless Carbon Steel Boiler Tubes for High-Pressure Service


1 Scope
1.1 This standard applies to seamless carbon steel boilers and superheater tubes with minimum wall thickness for rolling.
1.2 The general dimensions and thickness of the pipe provided by the standard are: outer diameter 1/2~7in. (12.7~177.8mm), minimum wall thickness 0.085~ l.00in. (2.2~25.4mm). Pipes of other sizes are also available, but these pipes are to comply with all other requirements of this standard.
1.3 Mechanical performance requirements are not applicable to pipes with an inner diameter of less than 1/8 in. (3.2 mm) or a thickness of less than 0.015 in. (0.4 mm).
1.4 When these products are used in the ISO Boiler Construction Recommended Practices, the requirements of this standard are supplemented and replaced by the requirements of the A520 standard.
1.5 Values ​​expressed in inches per inch or SI units shall be considered as standard values. In this standard, SI units are shown in parentheses. Since the values ​​of the two unit systems are not exactly equal, the two unit systems must be used independently. If mixed, it will lead to inconsistency with this standard. Unless the standard number with the “M” mark is used in the order, it will be used in units of inches.

 
2 reference standard
2.1 ASTM Standard:
A450/A450M carbon steel, ferritic alloy steel and austenitic alloy steel pipe for General requirements.
A 520 complies with the requirements of ISO boiler construction recommendations for high temperature carbon steel seamless and resistance welded tubular products.
 

3 general requirements
3.1 The materials provided in accordance with this standard shall comply with the requirements of the current version A 450/A 450M, unless otherwise specified herein.
 

4 Ordering Information
4.1 The ordering unit that meets the requirements of this standard shall include the following items as needed to fully explain the required materials:
4.1, 1 quantity (feet, meter or number of roots).
4.1.2 Material name (seamless tube).
4.1.3 Manufacturing (hot finishing or cold drawing).
4.1.4 size (outer diameter and minimum wall thickness).
4.1.5 length (fixed or indefinite).
4.1.6 Selective requirements (Section 8).
4.1.7 Required test report (see section A) of the A 450/A 450M standard.
4.1.8 Standard number.
4.1.9 Special requirements.

5 manufacturing
5.1 Pipes are manufactured by seamless pipe making method, which can be hot rolled or cold drawn according to specified requirements.

6 Heat treatment
6.1 Hot rolled tubes do not require heat treatment. After the cold drawing, the cold drawn tube shall be heat treated at 1200 °F (650 °C) or higher.
 
 
7 Chemical composition

Material	Chemical Composition(%)
	C	Si	Mn	P	S
ASTM A192	0.06~0.18	≤0.25	0.27~0.63	≤0.035	≤0.035

8 finished product analysis
8.1 When the buyer orders the order, the supplier shall perform the analysis of the finished product, the size of which exceeds 3 in. (76.2 mm)); take one tube per 100 pairs, the size is less than or equal to 3 in. (76.2 mm). Take one pipe for every 250; if the pipe is the same furnace, take one pipe for each furnace for analysis. Its chemical composition should meet the requirements of the regulations.
8.2 If the original finished product is unqualified, add two billets or tubes for retesting. For the problematic element, both retests must meet the requirements of the standard. Otherwise, the furnace or the batch (note) all remaining materials should be rejected, or the manufacturer is willing to perform individual acceptance tests for each billet or tube. Billets or tubes that do not meet the standard requirements should be rejected.
 
Note: For tubes with a size of 3 in. (76.2 mm) or less, each batch consists of 250 tubes; for sizes larger than 3 im (76.2_), 100 tubes per batch, before cutting the cut length.
 
 
9 Mechanical Properties
9.1 The hardness of the pipe shall not exceed the following values.

Brinell hardness (wall thickness greater than or equal to 0.200 in. (5.1mm)	Rockwell hardness (wall thickness is less than 0.200 in. (5.1mm)
137 HB	77 HRB

Material	Mechanical property
	Tensile Strength(MPa)	Yield Strength(MPa)	Elongation δ(%)	Hardness (HRB)
ASTM A192	≥325	≥180	≥35%	≤77

10 required mechanical properties test
10.1 Flattening test - Take 2 tubes per batch or the rest, and perform a flattening test on each sample at each end.
10.2 Flare test—Two tubes are taken from each batch or the remainder, and a flare test is performed on each sample at each end. These two pipes should be different from the two taken for the flattening test.
10.3 Hardness test - A Brinell or Rockwell hardness test is performed on a sample of 2 tubes per batch. The term “batch” applies to all tubes of the same furnace, the same nominal diameter, and the same wall thickness before cutting. When the final heat treatment is carried out in a periodic furnace, a batch of all the tubes including only the same size and the same heat number are heat-treated under the same heat treatment furnace. When the final heat treatment is carried out in a continuous furnace, the batch includes the same Dimensions, same calories, and all tubes with the same temperature, the same heating time and furnace speed in the same furnace.
10.4 Hydrostatic test—Each pipe shall be tested for water pressure or may be replaced by a non-destructive test when specified by the purchaser.
 
 
11 molding operation
11.1 The pipes inserted into the boiler shall be capable of withstanding expansion and curling without cracks or hair lines. The superheater tubes shall be capable of withstanding all forging, welding and bending processes that must be applied without defects.
 
 
12 product logo
12.1 In addition to the markings specified in the A 450/A 450M standard, the marking shall include the words that the pipe is hot finished or cold finished.