Alloy Steel P11 Seamless Pipe, ASTM A335 / ASME SA335, Chrome Moly

Product Description

What it is and the standard

ASTM A335 Grade P11 is seamless chrome-moly alloy steel pipe (1.25Cr-0.5Mo-Si) for high-temperature service. ASTM A335/A335M (active edition A335/A335M-26) covers seamless ferritic alloy-steel pipe in nominal and minimum wall, suitable for bending, flanging and fusion welding. ASME SA-335 is its counterpart in the ASME Boiler and Pressure Vessel Code Section II-A; mills certify the pipe to A335/SA-335.

Molybdenum raises high-temperature (creep) strength and chromium raises oxidation resistance. P11 is weldable; preheat and post-weld heat treatment may be needed to prevent cracking. Heat treatment is full or isothermal annealing, or normalizing and tempering, with tempering at 650 C (1200 F) minimum.

Grade, chemistry and equivalents

Mechanical properties (minimum): tensile strength 415 MPa (60 ksi), yield strength 205 MPa (30 ksi), elongation 30% longitudinal / 20% transverse.

• UNS: K11597
• ASME: SA-335 Gr. P11
• EN 10216-2: 13CrMo4-5 (1.7335) is the nearest European grade, not identical (1Cr-0.5Mo, lower Si)
• JIS G 3458: STPA23, comparable chemistry

Sizes and dimensions

Dimensions to ASME B36.10M. Typical range NPS 1/2 to 24 (15 NB to 600 NB), OD 21.3 mm to 610 mm, in Sch 10, 20, 30, 40, STD, 60, 80, XS, 100, 120, 140, 160 and XXS. In Sch 40, 80, 160 and XXS the wall runs from 2.77 mm (NPS 1/2 Sch 40) to 59.54 mm (NPS 24 Sch 160). Example: NPS 4 Sch 80 is 114.3 mm OD x 8.56 mm wall, 22.32 kg/m (B36.10M plain-end mass).

Hot finished or cold drawn. Plain ends or bevelled ends (37.5 degrees, for butt welding). Mill finish with dark blue-grey oxide scale, uncoated. Usual trade lengths are 6 m, 12 m or cut lengths. A size table with OD, wall and kg/m for Sch 40, 80, 160 and XXS is in the listing images.

Standards and tests

Tests required by ASTM A335:

• Hydrostatic test on each length
• Nondestructive examination of each pipe by a method permitted by the specification
• Tension test (transverse or longitudinal)
• Flattening test
• Hardness or bend test
• Chemical analysis to Table 1

Supplementary requirements S1 to S9, PMI, UT and third-party inspection apply only when ordered. Supply is usually against EN 10204 type 3.1 inspection certificates, which cover only the tests they report; type 3.2 adds endorsement by the purchaser's representative or an inspector designated by official regulations. If service will exceed 600 C (1100 F), state it in the enquiry.

Applications and industries

• Power station steam piping, high-temperature steam lines and steam headers
• Boiler superheater and reheater piping
• Refinery fired-heater transfer lines
• Refinery and petrochemical high-temperature process piping
• Heat exchangers, and pressure piping in HRSGs and process boilers
• Header and manifold fabrication

Industries: thermal and captive power plants, boiler manufacturers, oil refineries, petrochemical, fertilizer, sugar co-generation, chemical, EPC and piping contractors, HRSG and waste-heat boiler makers.

Supply from Allied Metal & Tubes

• Stockists and dealers of stainless steel pipes, tubes, sheets and plates, carbon steel seamless pipes, alloy steel pipes and other ferrous and non-ferrous metals
• Based in Khetwadi, Mumbai, Maharashtra; established 1993
• MSME registered; ISO 9001:2015 certified
• Main domestic market: all India
• IBR-certified pipe with Form III-A can be supplied for this range on request

FAQ

Is ASTM A335 P11 the same as ASME SA335 P11?
SA-335 is the ASME Section II-A counterpart of A335. Mills certify the pipe to A335/SA-335, and SA-335 is the designation referenced in ASME pressure codes.

Can you supply P11 pipe with IBR Form III-A?
Yes. IBR-certified pipe with Form III-A (Certificate of Manufacture and Test for Pipes) can be supplied for this range on request.

Are PMI and UT included with the mill certificate?
Not by default. A 3.1 certificate covers only the tests it reports; PMI, UT and third-party inspection must be ordered separately.