Seamless Pipes For High Temperature

Seamless pipes for high temperature are a type of steel pipe specifically designed to withstand high-temperature environments.

High Temperature service Alloy Steel tube are known as Chrome Moly pipe.

Basically there are three types of High Temperature Steel Pipe:

High Temperature Carbon Steel pipe
High Temperature Alloy Steel pipe
High Temperature Stainless Steel tube

Seamless Pipes For High Temperature are produced without any welding or joining, which ensures that they have a homogeneous and consistent structure that can withstand thermal expansion and contraction without being deformed or ruptured.

Seamless pipes for high temperature typically have a chemical composition that includes chromium (Cr), molybdenum (Mo), and other alloying elements that enhance their resistance to high temperatures and corrosion. The exact chemical composition depends on the specific grade and application requirements.

Seamless pipes for high temperature are commonly used in various industries such as power generation, chemical processing, oil and gas, and mechanical engineering. They are often used in applications where high-temperature steam or fluids need to be transported, such as in boilers, heat exchangers, and superheaters.

The advantages of using seamless pipes for high temperature include:

High-temperature resistance: Seamless pipes for high temperature are capable of withstanding high temperatures and pressures without being deformed, fractured or corroded.
Corrosion resistance: Seamless pipes for high temperature have excellent corrosion resistance properties, which makes them suitable for use in harsh environments.
Safety: Seamless pipes for high temperature are reliable and safe, providing a secure means for transporting fluids at high temperatures and pressures.
Easy installation: Seamless pipes for high temperature are easy to install and can be easily integrated into existing piping systems, reducing downtime and maintenance costs.

Overall, seamless pipes for high temperature are an important component of industrial piping systems, providing reliable and efficient means for transporting fluids at high temperatures and pressures.

High Temperature Carbon Steel tube

ASTM A179, A192, A210 specification covers Carbon Steel Seamless tube for high-temperature service. These pipe are used heat exchangers, condensers, High Temperature Material should furnish to Specification A 530.

GB5310-2008 is applicable to seamless tubes for making steam boiler whose pressure is high or higher and seamless tubes used as pipelines.
ASTM A179 / A179M – 90a Standard Specification for Seamless Cold-Drawn Low-Carbon Steel Heat-Exchanger and Condenser Tubes
ASTM A192 / A192M Standard Specification for Seamless Carbon Steel Boiler Tubes for High-Pressure Service
ASTM A210/ASME SA210 Standard Specification for Seamless Medium-Carbon Steel Boiler and Superheater Tubes.

Chemical Compositions(%) of GB 5310

Steel Grade	C	Si	Mn	S	P	Cr	Mo	V	Ti	B	W	Ni	Al	Nb	N
Steel Grade	C	Si	Mn	S	P	Cr	Mo	V	Ti	B	W	Ni	Al	Nb	N
20G	0.17-0.23	0.17-0.37	0.35-0.65	0.015	0.025
20 MnG	0.17-0.24	0.17-0.37	0.70-1.00	0.015	0.025
25MnG	0.22-0.27	0.17-0.37	0.70-1.00	0.015	0.025
15MoG	0.12-0.20	0.17-0.37	0.40-0.80	0.015	0.025		0.25-0.35
20MnG	0.15-0.25	0.17-0.37	0.40-0.80	0.015	0.025		0.44-0.65
12CrMoG	0.08-0.15	0.17-0.37	0.40-0.70	0.015	0.025	0.40-0.70	0.40-0.55
15CrMoG	0.12-0.18	0.17-0.37	0.40-0.70	0.015	0.025	0.80-1.10	0.40-0.55
12Cr2MoG	0.08-0.15	≤0.60	0.40-0.60	0.015	0.025	2.00-2.50	0.90-1.13
12Cr1MoVG	0.08-0.15	0.17-0.37	0.40-0.70	0.010	0.025	0.90-1.20	0.25-0.35	0.15-0.30
12Cr2MoWVTiB	0.08-0.15	0.45-0.75	0.45-0.65	0.015	0.025	1.60-2.10	0.50-0.65	0.28-0.42	0.08-0.18	0.002-0.008	0.30-0.55
10Cr9Mo1VNbN	0.08-0.12	0.20-0.50	0.30-0.60	0.010	0.020	8.00-9.50	0.85-1.05	0.18-0.25				≤0.040	≤0.040	0.06-0.10	0.03-0.07

Manufacturing methods

Steel smelting method
High-quality carbon structural steel and alloy structural steel shall be smelted by electric furnace plus furnace refining, oxygen converter plus furnace refining or electroslag remelting method, and steel refined outside the furnace shall be subjected to vacuum degassing treatment.

10Cr9Mo1VNbN, 10Cr9MoW2VNbBN, 10Cr11MoW2VNbCu1BN, 11Cr9Mo1W1VNbBN and stainless (heat-resistant) steel should be smelted by electric furnace plus furnace refining or electroslag remelting. The steel refined outside the furnace should be vacuum degassed.

After consultation between the supplier and the buyer, and indicating in the contract, other higher-required smelting methods may be adopted. When the purchaser specifies a certain smelting method, it should be indicated in the contract.

Manufacturing methods and requirements for tube blanks
The tube blank can be produced by continuous casting, die casting or hot rolling (forging).
Continuous casting tube blanks shall comply with the provisions of YB/T 4149, in which the level of low-fold structural defects shall not exceed 1; the hot-rolled (forged) tube blanks shall comply with the provisions of YB/T ××××; It is carried out in accordance with the regulations for hot-rolled (forged) tube blanks.

Manufacturing method of steel pipe
Steel pipes shall be manufactured by hot rolling (extrusion, expansion) or cold drawing (rolling). Steel pipes of grade 08Cr18Ni11NbFG shall be manufactured by cold drawing (rolling) seamless method.

Delivery status

The steel pipe shall be delivered in a heat treated condition. The heat treatment system for steel pipes shall comply with the requirements of Table 4. The heat treatment system for steel pipes should be filled in the quality certificate.

Mechanical Properties of GB5310

Grade	Tensile strength (Mpa)	Yield point(Mpa) not less than	Elongation(%) not less than	Impact(J) not less than
20G	410-550	245	24/22	40/27
25MnG	485-640	275	20/18	40/27
15MoG	450-600	270	22/20	40/27
20MnG	415-665	220	22/20	40/27
12CrMoG	410-560	205	21/19	40/27
12Cr2MoG	450-600	280	22/20	40/27
12Cr1MoVG	470-640	255	21/19	40/27
12Cr2MoWVTiB	540-735	345	18	40/27
10Cr9Mo1VNb	≥585	415	20	40
1Cr18Ni9	≥520	206	35
1Cr19Ni11Nb	≥520	206	35

Chemical Components (%) of ASTM A179

C	Si	Mn	P	S	Mo	Cr	V
0.06-0.18	/	0.27-0.63	≤0.035	≤0.035	/	/	/

Mechanical Properties of ASTM A179

Tensile Strength (Mpa)	Yield Strength (Mpa)	Elongation (%)	Hardness (HRB)
≥325	≥180	≥35	≤72

Chemical Components (%) of ASTM A192

Element	Content, %
C	0.06~0.18
Mn	0.27~0.63
P	≤0.035
S	≤0.035
Si	≤0.25

Mechanical Properties of ASTM A192

Mechanical Property Requirements	Data
T.S. min ksi [MPa]	47 [325]
Y.S. min ksi [MPa]	26 [180]
El. in 2" min, %	35
Brinell Hardness max. HBW	137
Rockwell Hardness, max. HRBW	77

Chemical Components (%) of ASTM A210

Steel Grade	C	Si	Mn	S	P

A 210A1 SA-210A1	≤0.27	≥0.10	≤0.93	0.020	0.025
A 210C SA-210C	≤0.35	≥0.10	0.29-1.06	0.020	0.025

Mechanical Properties of ASTM A210

Grade	Tensile strength (Mpa)	Yield point(Mpa) not less than	Elongation(%) not less than	Impact(J) not less than	Hardness not less than
A210 A1/ SA-210A1	≥415	255		"	79HRB
A210C/ SA-210C	≥485	275		"	89HRB

The properties of ASTM A210 steel include two common variations. This page shows summary ranges across both of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare ASTM A210 steel to: wrought carbon or non-alloy steels (top), all iron alloys (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.

High Temperature Alloy Steel tube

ASTM A213, A209 specification covers Alloy Steel Seamless tube for high temperature service. These tube are suitable for bending and similar forming operations, and for fusion welding at high temperatures. High Temperature Alloy Steel tube are also considered as low Alloy Chrome Moly grades.

ASTM/ASME A/SA213 Gr. T2, T5, T5b, T5c, T11, T12, T17, T21, T22, T9, T91
ASTM/ASME A/SA335 Gr. P1, P2, P5, P11, P12, P22
EN10216-2 Gr. 10CrMo9-10,13CrMo4-5,EN10216-2,P195GH,P235GH,P265GH

High Temperature Stainless Steel tube

High temperature stainless steel tubing maintain their mechanical properties when exposed to elevated temperatures on either a short- or long-term basis.

High Pressure and Temperature Service Seamless Pipes are application for heating-pipelines, containers, coal-saving devices superheaters and reheaters of high temperature and high press boiler by the main standard:

Application:

heating-pipelines, containers, coal-saving devices superheaters and reheaters of high temperature and high press boiler(P>=9.8MPa, T>450oC)

Available Sizes:

O.D.: from 3/4 to 20 inch
W.T.: 0.102 to 4inch (2.6 to 100 mm)
Length: max 16000mm

Marking:

Pipes are supplied with marking according to standard and customer request.
Marking is paint on the ends of pipes.
The same data, as well as additional information per customer’s request, is indicated on the bundle’s tags.

Delivery:

Pipes are supplied in hexagonal bundles or round bundles tied with steel strip.
Weight of bundle – up to 5000 kg upon request of customer.
Each bundle is furnished with three tags.

High pressure seamless pipe hydrostatic testing and eddy current testing

First, high pressure seamless pipe quality problems

Boilers with high pressure seamless pipe is an important material for manufacturing boiler pipe, the quality of how it will be directly related to the the boiler manufacture of quality so that the quality of the installation and use of quality. High pressure seamless steel quality should by steel pipe factory to make a guarantee, but in the case of short supply, the use of high-pressure supplied to the boiler manufacturers seamless steel pipe always found some quality problems, it made boiler pressure components such as water wall tubes, convection tubes, superheater tubes, heat exchanger tubes leaking or burst pipes phenomenon have occurred, has become a big problem that plagued boiler product quality, this boiler manufacturers and users are opinions.

In the case of a seller’s market, the boiler manufacturer almost assume full responsibility for the material supply side, including; how to control the quality of the boiler tube is now a boiler manufacturers are increasingly concerned about the problem, the solution is no more than two : a root-by high pressure seamless steel pressure test; another high pressure seamless implementation of 100% eddy current testing.

Second, high pressure seamless pipe defects and injuries

Excellent metal materials in accordance with the point of view of materials science, chemical composition, physical properties, geometry should be continuous, pure and uniform. If these three are deficient or damaged by a metal material, it is considered defective. If the metallic material is a discontinuity exists in geometry (i.e. does not close or not dense or non-dense), for example, cracking, shrinkage, from the skin, the dimple, layered, pinholes, slag, etc. Scar (referred to as the injury) exists that the metal material, it does not include the discontinuous chemical composition or physical properties of discontinuous.

As can be seen from here, defects contains wounded. The boiler steel smelting and rolling process in the same possible defects and injuries. According to Steel Pipe Plant, boiler tube defects (here mainly refers to the injury), mainly in the surface, more than the inner surface and the outer surface. Raw material (billets), about 70% of these defects from billet enough oxygen blowing in the slag material, shrinkage and other remnants of folders, use it rolling steel pipe there may be transverse cracks, mezzanine, folding, heavy leather defects longitudinal cracks are mostly the strain caused by the rolling. If these defects or wounds in the high pressure seamless, it appears that the material is not continuous, the compactness of the material inside the damage in the hydrostatic test, there may be leaks, made of boiler pressure parts running is likely to leak or burst pipe. Because of this, in order to ensure the quality of boiler tube, whether Chinese or foreign boiler seamless steel tubes for standard defined as a process performance guarantee, the pipe should be out by the root for hydrostatic testing.

Third, the hydrostatic test of the boiler tube density test

Is generally believed that the purpose of hydrostatic testing two types: one is the hydrostatic testing of the craft, its purpose is to test materials (or components) for leaks, the sealing performance of the test material; another confirmatory hydrostatic test, the aim is to test the strength of the material (or member) whether sufficient.

From here we can see, the hydrostatic test of the boiler tube is the process of hydrostatic test, material density test, the test material is continuous and whether dense; it is not to verify the strength test. Seen from the strength of the material mechanics theory, seamless steel tubes are thin and long component, its small diameter, thin tube wall thickness thinner under a lot of pressure.