Overview of alloy steel pipe
An Alloy Steel Pipe is used in applications which require moderate corrosion resistance properties with good durability and at an economical cost. To simply put it, alloy pipes are preferred in those areas where carbon steel pipes may fail. There are two classes of alloy steels - high alloys and low alloy steels. Pipes that constitute low alloy steels have an alloying content that ranges below 5%. Whereas the alloying content of a high alloy steel would range between 5% to about 50%. Similar to most alloys the working pressure ability of an Alloy Steel Seamless Pipe is about 20% higher than a welded pipe. So in applications that have a higher working pressure as a prerequisite, the use of a seamless pipe is justified. Though stronger than a welded pipe, the cost is much higher. Furthermore, the risk of intergranular corrosion at the heat affected weld zone is more in a welded product. The visible difference between an Alloy Steel Welded Pipe and a seamless product is the latitudinal seam along the length of the pipe. However, today, with the advancement in technology, the seam present on the Alloy Steel ERW Pipe could considerably be reduced via means of a surface treatment, such that it remains invisible to human eyes.
Alloy Steel Tube & Pipe Specification (Seamless/ Welded/ ERW)
Specifications | ASTM A 335 ASME SA 335 |
Standard | 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 |
Types Of Alloy Steel Seamless Tubes
15cr mo alloy solid steel pipes
25crmo4 alloy steel pipe
36 inch ASTM A 335 Grade P11 alloy galvanized steel pipe
42CrMo/ SCM440 alloy steel seamless pipe
Alloy 20/21/33 steel pipe
40MM alloy steel pipe
ASTM A355 P22 Seamless Alloy Steel Pipe
ASTM A423 Alloy Steel Seamless Pipe
Galvanized low alloy coated steel pipe
Alloy Steel ERW Pipes Chemical Properties
Alloy Steel | |||||||
C | Cr | Mn | Mo | P | S | Si | |
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 Characteristics Alloy Steel Chrome moly Pipes
Tensile Strength, MPa | Yield Strength, MPa | Elongation, % |
415 min | 205 min | 30 min |
Outside Diameter & Tolerance of ASME SA335 Alloy Pipe
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 Grade Pipes 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] |
Alloy Steel Seamless Tubes Application Industries
● Off-Shore Oil Drilling Companies
● Power Generation
● Petrochemicals
● Gas Processing
● Specialty Chemicals
● Pharmaceuticals
● Pharmaceutical Equipment
● Chemical Equipment
● Sea Water Equipment
● Heat Exchangers
● Condensers
● Pulp and Paper Industry