Alloy Steel Pipes and Tubes manufacturer and Supplier in India

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Alloy steel pipes and tubes are made from a combination of iron and alloying elements like chromium, molybdenum, nickel, vanadium, etc. to enhance strength, resistance to heat, toughness and resistance to corrosion. They are made in seamless, welded, ERW and fabricated forms for high pressure and high temperature applications in demanding industrial environments. These all the materials are manufactured according to the user requirements in different grades such as P5, P9, P11, P12, P21, P22 and P91. They have excellent mechanical properties and long service life which makes them a preferred material choice for critical process systems. Kalpataru Piping is one of the reliable manufacturers and suppliers of Alloy Steel Pipes and Tubes in India and supplies the precision engineered product in various grades, size, schedule and custom specification with a tight quality control, quick delivery globally.

Specifications of Alloy Steel Pipes and Tubes

Parameter / Feature	Specification Details
Material Specifications	ASTM A335, ASME SA335
Dimensional Standards	ASTM, ASME, and API
Commonly Supplied Grades	ASTM A335: Gr. P5, P9, P11, P12, P21, P22, P91 ASTM A213: T5, T9, T11, T12, T22, T91
Pipe Size Range	1/8″ NB to 30″ NB
Tubing Size Range	1/2” OD up to 5” OD (Custom diameters also available)
Outer Diameter (OD)	6 mm – 2500 mm
Wall Thickness (WT)	1 mm – 200 mm
Schedules	SCH 20, SCH 30, SCH 40, STD, SCH 60, SCH 80, XS, SCH 120, SCH 140, SCH160, XXS
Manufacturing Types	Seamless / Fabricated
Available Forms	Round, Square, Rectangular, Hydraulic etc
Standard Lengths	Within 13500 mm (Single Random, Double Random & Cut Length)
End Finishes	Plain End, Beveled End, Threaded

Chemical Composition of Alloy Steel Pipes and Tubes

Grade	UNS Number	Carbon (C)	Manganese (Mn)	Phosphorus (P)	Sulfur (S)	Silicon (Si)	Chromium (Cr)	Molybdenum (Mo)
P1	K11522	0.10 ~ 0.20	0.30 ~ 0.80	0.025 max	0.025 max	0.10 ~ 0.50	—	0.44 ~ 0.65
P2	K11547	0.10 ~ 0.20	0.30 ~ 0.61	0.025 max	0.025 max	0.10 ~ 0.30	0.50 ~ 0.81	0.44 ~ 0.65
P5	K41545	0.15 max	0.30 ~ 0.60	0.025 max	0.025 max	0.50 max	4.00 ~ 6.00	0.44 ~ 0.65
P5b	K51545	0.15 max	0.30 ~ 0.60	0.025 max	0.025 max	1.00 ~ 2.00	4.00 ~ 6.00	0.44 ~ 0.65
P5c	K41245	0.12 max	0.30 ~ 0.60	0.025 max	0.025 max	0.50 max	4.00 ~ 6.00	0.44 ~ 0.65
P9	S50400	0.15 max	0.30 ~ 0.60	0.025 max	0.025 max	0.50 ~ 1.00	8.00 ~ 10.00	0.44 ~ 0.65
P11	K11597	0.05 ~ 0.15	0.30 ~ 0.61	0.025 max	0.025 max	0.50 ~ 1.00	1.00 ~ 1.50	0.44 ~ 0.65
P12	K11562	0.05 ~ 0.15	0.30 ~ 0.60	0.025 max	0.025 max	0.50 max	0.80 ~ 1.25	0.44 ~ 0.65
P15	K11578	0.05 ~ 0.15	0.30 ~ 0.60	0.025 max	0.025 max	1.15 ~ 1.65	—	0.44 ~ 0.65
P21	K31545	0.05 ~ 0.15	0.30 ~ 0.60	0.025 max	0.025 max	0.50 max	2.65 ~ 3.35	0.80 ~ 1.60
P22	K21590	0.05 ~ 0.15	0.30 ~ 0.60	0.025 max	0.025 max	0.50 max	1.90 ~ 2.60	0.87 ~ 1.13
P91	K91560	0.08 ~ 0.12	0.30 ~ 0.60	0.020 max	0.010 max	0.20 ~ 0.50	8.00 ~ 9.50	0.85 ~ 1.05
P92	K92460	0.07 ~ 0.13	0.30 ~ 0.60	0.020 max	0.010 max	0.50 max	8.50 ~ 9.50	0.30 ~ 0.60

Mechanical Properties of Alloy Steel Pipes and Tubes

Grade Class	Tensile Strength (Min)	Yield Strength (Min)	Elongation (Min)
P1 to P22 (Standard Ferritic)	415 MPa	205 MPa	30%
P91 (Creep-Resistant Class)	585 MPa	415 MPa	20%
P92 (High-Strength CSEF Class)	620 MPa	440 MPa	20%

Equivalent Grades of Alloy Steel Pipes and Tubes

ASTM / ASME Grade	European (EN 10216-2) Equivalent	German (DIN 17175) Equivalent	Japanese (JIS G3462) Equivalent
ASTM A335 P5	X11CrMo5	12CrMo195	STBA 25
ASTM A335 P11	13CrMo4-5	13CrMo44	STBA 23
ASTM A335 P22	10CrMo9-10	10CrMo910	STBA 24
ASTM A335 P91	X10CrMoVNb9-1	—	STBA 26
ASTM A335 P92	X10CrMoVNb9-2	— (No direct equivalent)	STBA 29

Heat Treatment Chart of Alloy Steel Pipes and Tubes

Grade	Heat Treatment Type	Normalizing Temperature Range °F [°C]	Subcritical Annealing / Tempering Temperature Range °F [°C]
P5 (b, c)	Full or Isothermal Anneal	—	—
	Normalize and Temper	—	1250 [675] min
	Subcritical Anneal (P5c only)	—	1325 – 1375 [715 – 745]
P9	Full or Isothermal Anneal	—	—
	Normalize and Temper	—	1250 [675] min
P11	Full or Isothermal Anneal	—	—
	Normalize and Temper	—	1200 [650] min
P22	Full or Isothermal Anneal	—	—
	Normalize and Temper	—	1250 [675] min
P91	Normalize and Temper	1900 – 1975 [1040 – 1080]	1350 – 1470 [730 – 800]
	Quench and Temper	1900 – 1975 [1040 – 1080]	1350 – 1470 [730 – 800]

Wall Thickness Chart of Alloy Steel Pipes and Tubes

OD to Wall Thickness Ratio	Additional Permitted Ovality Tolerance
OD / WT Ratio ≥ 250	4.0% of nominal OD
OD / WT Ratio 100 to 250	3.0% of nominal OD
OD / WT Ratio 50 to 100	2.0% of nominal OD
OD / WT Ratio < 50	Under standard limits

Types of Alloy Steel Pipes and Tubes

Alloy Steel P9 Pipes and Alloy Steel P9 Tubes

Alloy Steel P11 Pipes and Alloy Steel P11 Tubes

Alloy Steel P12 Pipes and Alloy Steel P22 Tubes

Alloy Steel P22 Pipes and Alloy Steel P22 Tubes

Alloy Steel P91 Pipes and Alloy Steel P91 Tubes

Quality Testing and Inspection of Alloy Steel Pipes and Tubes

Alloy Tubing and Piping produced by Kalpataru Piping go through rigorous metallurgical and mechanical verification processes:

Positive Material Identification (PMI):
In-house results XRF test for chemical composition percentages prior to finishing.
Hydrostatic Pressure Testing:
Continuous water-pressure holds to confirm structural wall integrity.
Ultrasonic / Eddy Current Examinations:
Non-destructive high-resolution inspection of sub-surface cracking and/or micro-fissures.
Mechanical Proof Testing:
Coupon tests of tensile, yield, flattening and flaring.
Third-Party Witness:
Inspection services provided on request by global inspection/assessment organisations such as TUV, DNV, SGS, BV, Lloyds, etc.

Different Usage of Alloy Steel Pipes and Tubes

Grade Group	Primary Use Cases	Peak Operating Temp
P1, P2	General low-temperature process lines, mild-steam utility lines.	Under 450 °C (840 °F)
P5, P9	Petroleum refineries, catalytic crackers, sulfurous environments.	Up to 600 °C (1110 °F)
P11, P12	Superheaters, industrial boiler piping, chemical reactors.	Up to 560 °C (1040 °F)
P22	Main steam lines, power generation reheat systems.	Up to 580 °C (1075 °F)
P91, P92	Ultra-supercritical power plants, extreme high-pressure headers.	Up to 650 °C (1200 °F)

Frequently Asked Questions

What are alloy steel pipes and tubes?

Alloy steel pipes and tubes are steel products containing alloying elements like chromium, molybdenum, and nickel to improve strength, heat resistance, and corrosion resistance.

What are alloy steel pipes used for?

Alloy steel pipes are used in power plants, oil and gas, petrochemical, chemical processing, boilers, heat exchangers, and high-pressure piping systems.

What is the difference between alloy steel pipes and carbon steel pipes?

Alloy steel pipes contain additional alloying elements for better strength, heat resistance, and corrosion resistance, while carbon steel pipes mainly contain carbon and are used for general applications.

What are the advantages of alloy steel pipes and tubes?

Alloy steel pipes and tubes offer high strength, excellent heat resistance, good corrosion resistance, long service life, and reliable performance in demanding environments.

What is the difference between ASTM A335 and ASTM A213 alloy steel?

ASTM A335 covers seamless alloy steel pipes for high-temperature service, while ASTM A213 covers seamless alloy steel boiler, superheater, and heat exchanger tubes.

Are alloy steel pipes suitable for high-temperature applications?

Yes, alloy steel pipes are specifically designed to withstand high temperatures and pressures, making them ideal for boilers, power plants, and refineries.