ASTM A335 alloy steel pipe is an alloy steel pipe produced in accordance with the A335 standard established by the American Society for Testing and Materials (ASTM). This standard covers the specifications for seamless ferritic alloy steel pipes suitable for high temperature service. The ASTM A335 standard specifies a variety of ferritic steel grades, which generally do not exceed 10% chromium content and belong to the range of medium and low alloy steels. Different grades correspond to different chemical compositions to meet the needs under different working conditions.

ASTM A335 alloy steel pipe has high strength and good toughness, and can withstand stress under high temperature and high pressure environments. Under high temperature environment, the alloy steel pipe can maintain good mechanical properties. With the increase of temperature, the decrease in its strength and toughness is relatively small, and it has good high temperature endurance strength and creep properties. This enables it to operate stably for a long time under high temperature and high pressure working conditions, such as the steam piping system of thermal power plants, and is not prone to deformation and rupture.

ASTM A335 alloy steel pipe is widely used in high temperature piping systems in industries such as petroleum, chemical industry, and electric power due to its excellent high temperature resistance and good mechanical properties.

What does ASTM mean in piping?

ASTM International was first formed in 1898 by a group of scientists and engineers, led by US chemist, Charles Dudley. It was first formed in order to combat the frequent rail breaks that were disturbing the railroad industry.

The group originally developed a standard of steel that had to be adhered to if it was going to be used to fabricate train track rails and that is how the standards started.

ASTM currently has more than 30,000 members, there are 12,500 Global ASTM standards I operation globally and more than 140 countries use the standards and participate with them.

ASTM international has spent many years researching, examining, testing and defining a wide range of materials for the oil and gas industry.

The properties of the materials in question depend mainly on their chemical make-up and how it reacts and performs in different environments. Design temperatures and pressure as well as methods of manufacture of pipes, fittings, flanges, valves, nuts and bolts are also taken into consideration.

What is alloy steel pipe?

Alloy steel pipes are made from alloyed steel, a form of steel that contains various elements in varying proportions to give it certain desired characteristics. It usually consists of carbon plus any other element like Nickel, Manganese, Silicon or Chromium. This addition can improve the mechanical properties of these pipes, such as strength and corrosion resistance, and provide enhanced physical properties they may require for specific applications. These alloyed steels are available in different grades, allowing them to be used for various purposes across multiple industries due to their versatility and unique composition.

ASTM A335 Alloy steel pipes are highly specialized and popular in the industrial world. This composition gives them exceptional strength, durability, and resistance to corrosion. These pipes have various applications ranging from automotive to construction industries due to their ability to withstand high temperatures and pressures. Also, these steel pipes offer cost-effective solutions compared to other materials like stainless steel or carbon steel. With their superior properties and versatility, it’s not surprising that they are widely used in different industries worldwide.

What is ASTM A335 material?

ASTM A335 Pipe (ASME S/A335, Chorme-Moly) is a seamless ferritic Alloy-Steel Pipe for high temperature service.

A335 is often called chrome moly pipe because of the chemical makeup of Molybdenum (Mo) and Chromium (Cr). Molybdenum increases the strength of steel as well as the elastic limit, resistance to wear, impact qualities, and hardenability. Moly increases the resistance to softening, restrains grain growth and makes chromium steel less susceptible to embrittlement. Moly is the most effective single additive that increases high temperature creep strength. It also enhances the corrosion resistance of steel, and inhibits pitting. Chromium (or chrome) is the essential constituent of stainless steel. Any steel with 12% or more Chrome is considered stainless.

ASTM A335 Alloy Steel Pipe Specification

Processing Method:	Seamless and Welded
Size Range	1/8” – 48” / DN6 – 1200
Thickness Schedule	SCH 20- SCH 160, XXS
Length	6m or 12 m or Random
Standard	ASME B36.10
Surface Treatment	Blasting and Painting, Epoxy Powder FBE, 2PE, 3PE Coating
Material Grade	ASTM A335 P11 / P12 / P 5 / P9 / P91 / P92, A213 T11 / T12 / T22 / T5 / T9 / T91 / T92. 15CrMoG, 12Cr1MoVG, 12Cr5Mo, 1Cr5Mo, Cr9Mo, 10CrMo910, 12CrMo4-5

ASTM A335 Standard Scope

This specification2 covers nominal wall and minimum wall seamless ferritic alloy-steel pipe intended for hightemperature service. Pipe ordered to this specification shall be suitable for bending, flanging (vanstoning), and similar forming operations, and for fusion welding. Selection will depend upon design, service conditions, mechanical properties, and high-temperature characteristics.

 Heat Treatment:

All pipe shall be reheated for heat treatment and heat treated in accordance with the requirements of Table 2.

ASTM A335 Alloy Steel Pipe Chemical Composition

Grade		P-5	P-9	P-11	P-12	P-22	P-91	P-91 shall also include the following:
Element	UNS Designation	K41545	S50400	K11597	K11562	K21590	K91560
Carbon		0.15 max	0.15 max	0.05 – 0.15	0.05 – 0.15	0.05 – 0.15	0.08 – 0.12	V at 0.18 – 0.25
Manganese		0.30 – 0.60	0.30 – 0.60	0.30 – 0.60	0.30 – 0.61	0.30 – 0.60	0.30 – 0.60	N at 0.030 – 0.070
Phosphorous, max		0.025	0.025	0.025	0.025	0.025	0.02	Ni at 0.40 max
Sulfur, max		0.025	0.025	0.025	0.025	0.025	0.01	Al at 0.02 max
Silicon		0.50 max	0.25 – 1.00	0.50 – 1.00	0.50 max	0.50 max	0.20 -0.50	Cb at 0.06 – 0.10
Chromium		4.00 – 6.00	8.00 – 10.00	1.00 – 1.50	0.80-1.25	1.90 – 2.60	8.00 – 9.50	Ti at 0.01 max
Molybdenum		0.45 -0.65	0.90 – 1.10	0.44 – 0.65	0.44-0.65	0.87 – 1.13	0.85 – 1.05	Zr at 0.01 max

Tensile Requirements of Alloy Steel Seamless Pipes 

Seamless
	P-5	P-9	P-11	P-12	P-22	P-91
Tensile Strength, min., psi
ksi	60	60	60	60	60	85
MPa	415	415	415	415	415	585
Yield Strength, min., psi
ksi	30	30	30	32	30	60
MPa	205	205	205	220	205	415

Heat Treatment Requirements of Alloy Steel Seamless Pipes 

Grade	Heat Treatment Type	Normalizing Temperature Range F [C]	Subcritical Annealing or Tempering Temperature,min or range°F [°C]
P5 (b,c)	Full or isothermal Anneal	*****
	Normalize and Temper	*****	1250 [675]
	Subcritical Anneal (P5c only)	*****	1325 – 1375 [715 – 745]
P9	Full or isothermal Anneal	*****
	Normalize and Temper	*****	1250 [675]
P11	Full or isothermal Anneal	*****
	Normalize and Temper	*****	1200 [650]
P12	Full or isothermal anneal or	*****
	normalize and temper or	*****	1200 [650]
	subcritical anneal	*****	1200–1300 [650–705]
P22	Full or isothermal anneal or	*****
	Normalize and Temper	*****	1250 [675]
P91	normalize and temper or	1900-1975 [1040 – 1080]	1350-1470 [730 – 800]
	Quench and Temper	1900-1975 [1040 – 1080]	1350-1470 [730 – 800]

What is the material equivalent of A335?

Pipes / Tubes
Material number	EN	ASTM
Alloyed heat-resistant
1.5415     15 Mo 3	16Mo3	A 335 Grade P1
1.7335     13 CrMo 4 4	13CrMo4–5	A 335 Grade P12
1.7380     10 CrMo 9 10	10CrMo9–10	A 335 Grade P22
1.7362     12 CrMo 19 5	X11CrMo5	A 335 Grade P5
1.4903     –	X10CrMoVNb9–1	A 335 Grade P91

ASTM A335 Alloy Steel Pipe Dimension

ASTM A335 Alloy Steel Pipe specifications are mainly applicable to sizes ranging from 1/8” to 48” (DN6 to DN1200). The wall thickness of these steel pipes must comply with ASME B36.10 standards, and the wall thickness grades are SCH 10, SCH 20, SCH 40, STD, XS, SCH 100, SCH 120, SCH 160, XXS.

Elongation Requirements of Alloy Steel Seamless Pipes 
 

Calculated Minimum Elongation Values
Elongation in 2 in. or 50 mm, min %
Wall Thickness		P5, P9, P11,P12, P22,		P91
in.	mm	Longitudinal	Transverse	Longitudinal
5/16 (0.312)	8	30	20	20
9/32 (0.281)	7.2	28	19	19
1/4 (0.250)	6.4	27	18	18
7/32 (0.219)	5.6	26		17
3/16 (0.188)	4.8	24		16
5/32 (0.156)	4	22		15
7/8 (0.125)	3.2	21		14
3/32 (0.094)	2.4	20		13
1/18 (0.062)	1.6	18		12

Permissible Variations in Outside Diameter of Alloy Steel Pipes

1) For pipe ordered to NPS [DN] or outside diameter, variations in outside diameter shall not exceed those specified .

2) For pipe ordered to inside diameter, the inside diameter shall not vary more than +/- 1 % from the specified inside diameter.

NPS [DN] Designator	Over		Under
	in.	mm	in.	mm
1/8 to 1 1/2 [6 to 40], incl.	1/64 (0.015)	0.4	1/64 (0.015)	0.4
Over 1 1/2 to 4 [40 to 100], incl.	1/32 (0.031)	0.79	1/32 (0.031)	0.79
Over 4 to 8 [100 to 200], incl.	1/16 (0.062)	1.59	1/32 (0.031)	0.79
Over 8 to 12 [200 to 300], incl.	3/32 (0.093)	2.38	1/32 (0.031)	0.79
Over 12 [300]	+/- 1% of the specified outside diameter

ASTM A335 Alloy Steel Pipe Required Markings on Each Length

(On Tags attached to each Bundle in case of Bundled Pipe) Markings will adhere to prescribed specifications in A 999/A999M and be: Rolled, Stamped, or Stenciled (Mfrs. Option)

In addition, markings will include:	Marking to indicate the test method(s)
Length of pipe	Hydrostatic	Nondestructive	Marking
Schedule Number	YES	NO	Test Pressure
Heat Number or Manufacturer’s number by which heat can be identified	NO	YES	NDE
An Additional Symbol “S” if the pipe conforms to any Supplementary Requirements	NO	NO	NH
S1 – Product Analysis	YES	YES	Test Pressure/NDE
S2 – Transverse Tension Test
S3 – Flattening Test
S4 – Metal Structure and Etching Tests
S5 – Photomicrographs
S6 – Photomicrographs for Individual Pieces
S7 – Alternative Heat Treatment – Grade P91 (type 1 and 2)

What is the difference between ASTM A333 and A335?

Scope of application:

A335-This specification covers seamless ferritic alloy-steel pipe for high-temperature service.

A333-This specification covers wall seamless and welded carbon and alloy steel pipe intended for use at low temperatures.

Corresponding grade:

ASTM A333: Grade 1, Grade 3, Grade 4, Grade 6, Grade 7, Grade 8, Grade 9, Grade 10, Grade 11

ASTM A335: P1, P2, P5,P9, P11, P12, P21, P22, P23, P24, P91, P92

Non-destructive power measurement:

ASTM A333 requires non-destructive electrical measurements, manufacturer-selected non-destructive test types, manufacturer-selected non-destructive electrical tests or hydrostatic tests, or both

ASTM A335 requires non-destructive electrical measurements, selected by the manufacturer for non-destructive electrical measurements

hydrostatic test:

ASTM A333 requires a hydrostatic test, selected by the manufacturer for non-destructive or hydrostatic testing, or both

ASTM A335 requires hydrostatic testing, which can be replaced by a non-destructive electrical test, at the manufacturer’s discretion

Reference Documents

ASTM A999/A 999M Specification for General requirements for Alloy and Stainless Steel Pipe.

ASTM E 213 Practice for Ultrasonic Examination of metal Pipe and Tubing

ASTM E 309 Practice for Eddy-Current Examination of Steel Tubular Products Using Magnetic Saturation

ASTM E 381 Method of Macroetch testing Steel Bars, Billets, Blooms, and Forgings

ASTM E 570 Practice for Flux Leakage Examination of Ferromagnetic Steel Tubular Products

ASME B26.10M Welded and Seamless Wrought Steel Pipe

Ordering Information

Orders for material under this specification should include the following, as required, to describe the desired material adequately:

1. Quantity (feet, metres, or number of lengths),

2. Name of material (seamless alloy steel pipe),

3. Grade (Table 1),

4. Manufacture (hot-finished or cold-drawn),

5. Size using one of the following

6. NPS and schedule number

7. Outside diameter and nominal wall thickness

8. Outside diameter and minimum wall thickness

9. Inside diameter and nominal wall thickness, and

10. Inside diameter and minimum wall thickness.

11. Length (specific or random),

12. End finish (Ends Section of Specification A999/ A999M),

ASTM A335 Alloy Steel Pipe Exported Countries

We Export ASTM A335 Alloy Steel Pipe to Saudi Arabia, United Arab Emirates, Qatar, Bahrain, Oman, Kuwait, Turkey, Egypt, Yemen , Syria, Jordan, Cyprus, Singapore, Malaysia, Indonesia, Thailand, Vietnam, South Korea, Japan, Sri Lanka, Maldives, Bangladesh, Cambodia, Argentina, Bolivia, Brazil, Venezuela, Colombia, Ecuador, Guyana, Paraguay, Uruguay, United States Of America, Canada, Mexico, Panama, Jamaica, Bahamas, Denmark, Norway, Germany, France,Italy, United Kingdom, Spain, Belgium, Greece, Czech Republic, Portugal, Hungary, Albania, Austria, Finland, Ireland, Croatia, Malta, Nigeria, Algeria, Angola, South Africa, Libya, Egypt, Sudan,  Europe, Africa, Asia, North America, South America, Middle East.etc