Seamless Alloy Pipe Overview

 

We are dedicated to the production of high performance alloy seamless steel pipes. They contain various alloy elements such as silicon, chromium, manganese, and nickel. With their high chromium content, our alloy seamless steel pipes offer excellent high-temperature resistance, low-temperature resistance, and corrosion resistance. Therefore, they are widely used in the petroleum, chemical, power, and boiler industries.

We are specialized in manufacturing seamless steel pipes. The product specifications range from an outer diameter of Ф6mm to Ф114mm and a wall thickness of 0.8mm to 10mm. The main materials include high-quality carbon steel, alloy steel, low-temperature steel, corrosion-resistant steel, stainless steel, and nickel-based alloys, etc. The product types are cold-rolled seamless steel pipes, cold-drawn seamless steel pipes, and extra-long seamless coiled pipes. All products are manufactured in accordance with national standards, ASTM standards, European standards, enterprise standards, and customer requirements. And our annual output of various seamless steel pipes is 38,000 tons. Feel free to contac us.

Seamless Alloy Pipe Specification

Product Name	Seamless Alloy Pipe
Types	High – temp seamless ferritic alloy steel pipes, Ferritic and austenitic alloy steel tubes for boilers, superheaters and heat – exchangers
Standards	ASTM A335, ASTM A213
Dimensions	Diameter: 16 – 1016mm Thickness: 2 – 120mm
Steel Grades	P5, P9, P11, P12, P22, P91, P92 T5, T9, T11, T12, T22, T91
Surface Treatment	Oiled or black – painted for rust prevention
Application Fields	Industrial boilers, power plants, nuclear plants

Seamless Alloy Pipe Chemical Composition

ASTM A335 Seamless Alloy Pipe Chemical Composition

CHEMICAL	LIMITS	C	Mn	P	S	Si	Cr	Mo
ASTM A335 P5	MIN		0.30				4.0	0.44
	MAX	0.15	0.60	0.025	0.025	0.50	6.0	0.65
ASTM A335 P9	MIN		0.30			0.25	8.0	0.9
	MAX	0.15	0.60	0.025	0.025	1.00	10.0	1.1
ASTM A335 P11	MIN	0.05	0.30			0.50	1.00	0.44
	MAX	0.15	0.60	0.025	0.025	1.00	1.50	0.65
ASTM A335 P22	MIN	0.05	0.30				1.90	0.87
	MAX	0.15	0.60	0.025	0.025	0.50	2.60	1.13

ASTM A213 Seamless Alloy Pipe Chemical Composition

CHEMICAL	LIMITS	C	Mn	P	S	Si	Cr	Mo
ASTM A213 T5	MIN		0.30				4.00	0.450
	MAX	0.150	0.60	0.025	0.025	0.50	6.00	0.650
ASTM A213 T9	MIN		0.30			0.25	8.00	0.900
	MAX	0.150	0.60	0.025	0.025	1.00	10.00	1.100
ASTM A213 T11	MIN	0.050	0.30			0.50	1.00	0.440
	MAX	0.150	0.60	0.025	0.025	1.00	1.50	0.650
ASTM A213T12	MIN	0.050	0.30				0.80	0.440
	MAX	0.150	0.61	0.025	0.025	0.50	1.25	0.650
ASTM A213 T21	MIN	0.050	0.30				2.65	0.800
	MAX	0.150	0.60	0.025	0.025	0.50	3.35	1.060
ASTM A213 T22	MIN	0.050	0.30				1.90	0.870
	MAX	0.150	0.60	0.025	0.025	0.50	2.60	1.130
ASTM A213 T91	MIN	0.070	0.30			0.20	8.00	0.850
	MAX	0.140	0.60	0.020	0.010	0.50	9.50	1.050

Seamless Alloy Pipe Chemical Composition Tolerances

Element	Specified Element Limit (%, inclusive)	Tolerance Over Maximum Limit or Under Minimum Limit for Size Ranges Shown (%)
		100 in² (645 cm²) or less	Over 100 to 200 in² (645 to 1290 cm², inclusive)
Carbon	to 0.30	0.01	0.02
	over 0.30 to 0.75	0.02	0.03
	over 0.75	0.03	0.04
Manganese	to 0.90	0.03	0.04
	over 0.90 to 2.10	0.04	0.05
Phosphorus	over max, only	0.005	0.010
Sulfur	to 0.060	0.005	0.010
Silicon	to 0.35	0.02	0.02
	over 0.35 to 2.20	0.05	0.06
Nickel	to 1.00	0.03	0.03
	over 1.00 to 2.00	0.05	0.05
	over 2.00 to 5.30	0.07	0.07
	over 5.30 to 10.00	0.10	0.10
Chromium	to 0.90	0.03	0.04
	over 0.90 to 2.10	0.05	0.06
	over 2.10 to 3.99	0.10	0.10
Molybdenum	to 0.20	0.01	0.01
	over 0.20 to 0.40	0.02	0.03
	over 0.40 to 1.15	0.03	0.04
Vanadium	to 0.10	0.01	0.01
	over 0.10 to 0.25	0.02	0.02
	over 0.25 to 0.50	0.03	0.03
	min value specified, check under min limit	0.01	0.01
Tungsten	to 1.00	0.04	0.05
	over 1.00 to 4.00	0.08	0.09
Aluminum	up to 0.10	0.03	–
	over 0.10 to 0.20	0.04	–
	over 0.20 to 0.30	0.05	–
	over 0.30 to 0.80	0.07	–
	over 0.80 to 1.80	0.10	–

Seamless Alloy Pipe Manufacturing Process

We manufacture alloy seamless steel pipes with high quality materials. The production process mainly including steps such as piercing, hot rolling, cold rolling, or cold drawing:

• First, steel ingots or solid tube billets are pierced to form hollow shells.
• Then, the hollow shells are heated and hot – rolled to a certain specification.
• Next, cold rolling or cold drawing is followed to improve the precision and performance of the pipes.
• Throughout the entire process, the addition and control of alloy elements are crucial steps, which directly affect the performance and service life of the pipes.

Rolled round billets → Examination → Cut off → Heating → Piercing → Elongating → Slight – tension reducing → Straightening → Crop end cutting off → Visual inspection → Ndt → Hydrostatic test → Marking

Seamless Alloy Pipe Features

1. Excellent Corrosion Resistance:

Our alloy seamless steel pipes have multiple alloy elements added, such as chromium and molybdenum. These elements can significantly improve the pipes’ corrosion resistance and extend their service life.

2. Good High-temperature Resistance:

The alloy seamless steel pipes we manufacture have excellent high-temperature resistance. They can be used for a long time in high-temperature environments without being easily deformed or cracked. They are widely applied in high-temperature industrial fields such as petroleum, chemical industry, and electric power.

3. High Strength:

The strength of the alloy seamless steel pipes we produce is much higher than that of ordinary steel pipes. They can withstand greater pressure and tensile force. They are widely used in fields such as petroleum drilling and bridge construction.

4. High Precision:

The production process of our alloy seamless steel pipes is rigorous. They are manufactured with high precision, have no joints, and feature a good surface finish. These pipes are widely applied in fields such as precision instruments and aerospace.

ASTM A335 Seamless Alloy Pipe Mechanical Properties

MATERIAL	ASTM A335 P5	ASTM A335 P9	ASTM A335 P11	ASTM A335 P12	ASTM A335 P22	ASTM A335 P91
T.S (MPA)	415 min	415 min	415 min	415 min	415 min	620 min
Y.S (MPA)	205 min	205 min	205 min	205 min	205 min	415 min
EL %	30 min	30 min	30 min	30 min	30 min	20 min

Seamless Alloy Pipe Heat Treatment

P5, P9, P11, and P22
Grade	Heat Treatment Type	Normalizing Temperature Range F [C]	Subcritical Annealing or Tempering Temperature 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]
P22	Full or Isothermal Anneal
	Normalize and Temper	*****	1250 [675]
P91	Normalize and Temper	1900-1975 [1040 – 1080]	1350-1470 [730 – 800]
	Quench and Temper	1900-1975 [1040 – 1080]	1350-1470 [730 – 800]

Seamless Alloy Pipe Application

• Oil and Gas Industry
• Power Generation
• Chemical and Petrochemical Plants
• Aerospace Industry
• Automotive Industry
• Marine Industry
• Heat Exchanger and Boiler Tubes
• Industrial Equipment and Machinery