Alloy Steel Seamless Pipe is produced with the help of a single billet and without any welds. Alloy Pipes are available in sizes of ½ to 26mm. Alloy Steel pipes are very durable and easy to maintain. The Alloy Steel Welded Pipe is designed by welding pieces of steel together longitudinally. Alloy pipes have an outer thickness of 0.3-50mm. They can be availed in a beveled or a plain end. The Seamless Alloy Steel Pipe is costlier than the welded pipe as it has 20% extra working pressure. Alloy Steel pipes are furthermore resistant to corrosion. The Alloy Pipe Price depends on the wall thickness and the size of the pipe.
A product made of alloy steel performs far better than one made of carbon steel. Although they are less expensive than stainless steel grades, they have poorer corrosion resistance than stainless steels but are more resistant than carbon steel pipes. We offer ASTM A335 Alloy Pipe and ASTM A213 Alloy Tube at the best price in China. To know more about Alloy Steel Pipes & Tubes contact us today!
What Are Alloy Steel Pipes & Tubes?
One of the main reasons behind the popularity of alloy steel is its better performance than carbon steel. If we compare them, the alloy steel pipe can resist corrosion better than carbon steel pipes. The Alloy Pipe is also cheaper than the stainless steel variant. There are two types of Alloy Steel Pipe Material, the high alloy, and the low alloy. The alloying content of high alloys ranges between 5% to 50%, whereas it is below 5% in low alloys. For example, the alloying content of Seamless Alloy Steel Pipe is almost 20% higher than its welded variant. Alloy seamless pipes are always preferred for high-pressure environments, even though the seamless Alloy Pipe price is higher.
The Advantage of Alloy Steel Seamless Pipes & Tubes for High-Pressure Applications
High alloy steels and low alloy steels are the two types of alloy steels. Low alloy steel pipes are made up of pipes with an alloying percentage of less than 5%. A high alloy steel's alloying content would be anything from 5% to roughly 50%. An Alloy Steel Seamless Pipe's working pressure capability is around 20% higher than a welded pipe, similar to most alloys. As a result, the use of a seamless pipe is justified in applications that require a higher working pressure. The cost is substantially more than a welded pipe, despite the fact that it is stronger.
Alloy Steel Seamless Pipes & Tubes are utilised in applications that demand moderate corrosion resistance, as well as good durability and a low cost. The High Temperature Alloy Steel Boiler Pipe is typically utilised in applications where the ambient temperature reaches 500°C. For example, when used on drilling rigs, hollow and thin-walled Alloy Steel Drill Pipe must be able to withstand pressure differentials that occur both inside and outside these Alloy Steel Seamless Pipe.
Types of Alloy Steel Pipes & Tubes
Alloy steel pipes and tubes are specialized components made from steel alloyed with elements like chromium and molybdenum, enhancing their strength, corrosion resistance, and high-temperature performance. They are categorized by manufacturing process (seamless or welded) and specific grades like ASTM A335 P-grades for pipes and ASTM A213 T-grades for tubes.
Alloy Steel Pipe Specification
| Specifications |
ASTM A 335 ASME SA 335 |
| Dimensions |
ASTM, ASME and API |
| Size |
1/8″NB TO 30″NB IN |
| Tubing Size |
1 / 2” OD up to 5” OD, customs diameters also available |
| Outer Diameter |
6-2500mm; WT:1-200mm |
| Schedule |
SCH20, SCH30, SCH40, STD, SCH80, XS, SCH60, SCH80, SCH120, SCH140, SCH160, XXS |
| Grade |
STM A335 Gr. P5, P9, P11, P12, P21, P22 & P91, ASTM A213 – T5, T9, T11, T12, T22, T91, ASTM A691 |
| Length |
Within 13500mm |
| Type |
Seamless / Fabricated |
| Form |
Round, Hydraulic Etc |
| Length |
Single Random, Double Random & Cut Length. |
| End |
Plain End, Beveled End, Treaded |
Alloy Steel Pipes Chemical Composition
| Grade |
C |
Cr |
Mn |
Mo |
P |
S |
Si |
| Alloy Steel |
0.05 – 0.15 |
1.00 – 1.50 |
0.30 – 0.60 |
0.44 – 0.65 |
0.025 max |
0.025 max |
0.50 – 1.00 |
Mechanical Properties of Alloy Steel Pipes
| Tensile Strength, MPa |
Yield Strength, MPa |
Elongation, % |
| 415 min |
205 min |
30 min |
Alloy Steel pipes Diameter & Tolerance
| ASTM A450 |
Hot rolled |
Outside Diameter, mm |
Tolerance, mm |
| OD≤101.6 |
+0.4/-0.8 |
| 101.6＜OD≤190.5 |
+0.4/-1.2 |
| 190.5＜OD≤228.6 |
+0.4/-1.6 |
| Cold Drawn |
Outside Diameter, mm |
Tolerance, mm |
| OD＜25.4 |
±0.10 |
| 25.4≤OD≤38.1 |
±0.15 |
| 38.1＜OD＜50.8 |
±0.20 |
| 50.8≤OD＜63.5 |
±0.25 |
| 63.5≤OD＜76.2 |
±0.30 |
| 76.2≤OD≤101.6 |
±0.38 |
| 101.6＜OD≤190.5 |
+0.38/-0.64 |
| 190.5＜OD≤228.6 |
+0.38/-1.14 |
| ASTM A530 & ASTM A335 |
NPS |
Outside Diameter, inch |
Tolerance, mm |
| 1/8≤OD≤1-1/2 |
±0.40 |
| 1-1/2＜OD≤4 |
±0.79 |
| 4＜OD≤8 |
+1.59/-0.79 |
| 8＜OD≤12 |
+2.38/-0.79 |
| OD>12 |
±1% |
Alloy Steel Pipe Thickness
Alloy steel pipes range in thickness from 0.3 to 50 mm, with welded pipes typically measuring 1.0 to 15.0 mm. Seamless alloy steel pipes, while pricier, offer 20% greater working pressure than welded variants.
| Size |
1/8 NB To 26NB IN |
| Standards |
ASTM A335, ASME SA 335 |
| Type |
Seamless |
| Specialized in |
Large Diameter Size |
| Schedule |
SCH20, SCH30, SCH40,STD,SCH80, XS, SCH60, SCH120, SCH140, SCH160, XXS, Upto 4" Wall Thick |
| Form |
Round, Square, Rectangular, Hydraulic,etc. |
| Length |
Single Random, Double Random & Cut Length |
| Tubing End |
Plain End, Beveled End, Treaded |
Heat Treatment of Alloy Steel Pipes and Tubes
Heat treatment is a crucial process in the manufacturing and performance enhancement of alloy steel pipes and tubes. It involves controlled heating and cooling to alter the physical and mechanical properties of the steel without changing its shape. This process improves strength, hardness, ductility, toughness, and resistance to wear and corrosion.
Typical Heat Treatment Parameters for Alloy Steel Pipe Grades (ASTM A335 P-Grades & Equivalents)
| Grade |
Heat Treatment Type(s) Commonly Used for Supply/Processing |
Normalizing Temperature Range °F [°C] (Min, unless range given) |
Subcritical Annealing or Tempering Temperature Range °F [°C] (Min, unless range given) |
| P1 |
Normalize & Temper; Full Anneal |
1600 - 1750 [870 - 955] |
1150 - 1350 [620 - 730] |
| P2 |
Normalize & Temper; Full Anneal |
1650 - 1800 [900 - 980] |
1150 - 1350 [620 - 730] |
| P5, P5b |
Normalize & Temper; Full Anneal |
1650 [900] |
1250 [675] |
| P5c |
Normalize & Temper; Full Anneal |
1650 [900] |
1250 [675] (Titanium Stabilized) |
| P9 |
Normalize & Temper; Full Anneal |
1650 [900] |
1250 [675] |
| P11 |
Normalize & Temper; Full Anneal |
1650 [900] |
1200 - 1400 [650 - 760] |
| P12 |
Normalize & Temper; Full Anneal |
1650 [900] |
1200 - 1400 [650 - 760] |
| P22 |
Normalize & Temper; Full Anneal |
1650 [900] |
1250 - 1400 [675 - 760] |
| P23 (CSEF) |
Normalize & Temper |
1900 - 1975 [1040 - 1080] |
1350 - 1470 [730 - 800] |
| P91 (CSEF) |
Normalize & Temper |
1900 - 1975 [1040 - 1080] |
1350 - 1470 [730 - 800] (Min. 1350 [730]) |
| P92 (CSEF) |
Normalize & Temper |
1900 - 2012 [1040 - 1100] |
1350 - 1490 [730 - 810] (Min. 1350 [730]) |
Typical Heat Treatment Parameters for Alloy Steel Tube Grades (ASTM A213 T-Grades)
| ASTM A213 Grade |
Heat Treatment Type(s) Commonly Used for Supply/Processing |
Normalizing Temperature Range °F [°C] (Min, unless range given) |
Subcritical Annealing or Tempering Temperature Range °F [°C] (Min, unless range given) |
| T1 |
Normalize & Temper; Full Anneal |
1600 - 1750 [870 - 955] |
1150 - 1350 [620 - 730] |
| T2 |
Normalize & Temper; Full Anneal |
1650 - 1800 [900 - 980] |
1150 - 1350 [620 - 730] |
| T5, T5b |
Normalize & Temper; Full Anneal |
1650 [900] |
1250 [675] |
| T5c |
Normalize & Temper; Full Anneal |
1650 [900] |
1250 [675] (Titanium Stabilized) |
| T9 |
Normalize & Temper; Full Anneal |
1650 [900] |
1250 [675] |
| T11 |
Normalize & Temper; Full Anneal |
1650 [900] |
1200 - 1400 [650 - 760] |
| T12 |
Normalize & Temper; Full Anneal |
1650 [900] |
1200 - 1400 [650 - 760] |
| T22 |
Normalize & Temper; Full Anneal |
1650 [900] |
1250 - 1400 [675 - 760] |
| T23 (CSEF) |
Normalize & Temper |
1900 - 1975 [1040 - 1080] |
1350 - 1470 [730 - 800] |
| T91 (CSEF) |
Normalize & Temper |
1900 - 1975 [1040 - 1080] |
1350 - 1470 [730 - 800] (Min. 1350 [730]) |
| T92 (CSEF) |
Normalize & Temper |
1900 - 2012 [1040 - 1100] |
1350 - 1490 [730 - 810] (Min. 1350 [730]) |
Manufacturing Processes for Alloy Steel Pipes & Tubes: Seamless and Welded
Alloy Steel Seamless Pipes & Tubes
Our Alloy Steel Seamless Pipes and Alloy Steel Seamless Tubes are manufactured by piercing a solid high-quality alloy steel billet and then meticulously rolling or drawing it to precise final dimensions. This process ensures a homogenous structure without any weld seams.
These Seamless alloy steel pipe products offer uniform strength and excellent pressure integrity. They are generally the preferred choice for High-pressure alloy steel seamless pipe applications and other critical services where the absence of a weld seam is paramount for safety and reliability. The inherent structural integrity of a Seamless alloy steel tube, including Chrome moly seamless tube grades, makes them ideal for extreme conditions.
Welded Alloy Steel Pipes & Tubes (ERW, EFW, SAW):
Welded Alloy Steel Pipes & Tubes are produced by forming a flat alloy steel strip or plate into a cylindrical shape and then joining the seam using advanced welding techniques.
Modern welding methods such as ERW (Electric Resistance Welding), EFW (Electric Fusion Welding), and SAW (Submerged Arc Welding) are employed to produce high-quality, strong welds with consistent properties.
Welded options can often be more cost-effective, particularly for larger diameters, and are suitable for many applications where the specific benefits of Alloy Steel Seamless Pipes are not a critical design requirement.
The optimal choice between Alloy Steel Seamless Pipes & Tubes and their welded counterparts depends on specific application requirements, including design pressure, operating temperature, the nature of the corrosive environment, and overall project budget.
Applications & Industries Served by Alloy Steel Pipes & Tubes
The robust and versatile properties of Alloy Steel Pipes & Tubes, including our high-quality Alloy Steel Seamless Pipes and Alloy Steel Seamless Tubes, make them indispensable across a wide spectrum of demanding industries:
- Power Generation: Critical components such as main steam lines, reheater and superheater tubes (often Seamless alloy steel tube like Chrome moly seamless tube grades), boiler components, and feedwater heaters in fossil fuel, nuclear, and combined cycle power plants. High-pressure alloy steel seamless pipe is essential here.
- Oil & Gas: Exploration and production (OCTG), refining processes requiring Alloy Steel Seamless Pipes for high-temperature and corrosive services, transportation pipelines for sour gas and high-pressure fluids, and downhole equipment.
- Petrochemical & Chemical Processing: Reactor tubes, furnace components, process piping carrying high-temperature and corrosive chemicals, and heat exchangers often utilize durable Alloy Steel Seamless Tubes.
- Automotive & Aerospace: High-strength structural components, engine parts requiring superior heat resistance, and specialized exhaust systems.
- Heavy Machinery & Construction: Hydraulic systems demanding High-pressure alloy steel seamless pipe, high-strength structural members, and wear-resistant components.
- Shipbuilding & Marine: High-pressure piping systems and structural components exposed to corrosive saltwater environments, often utilizing specialized Alloy Steel Seamless Tubes.
