SS 316L Seamless Pipe - Stainless Steel ASTM A312 TP316L

Product Description

What It Is: ASTM A312 TP316L Seamless Pipe

SS 316L seamless pipe to ASTM A312/A312M grade TP316L (UNS S31603) and ASME SA-312, the designation referenced in ASME pressure codes. A312 covers austenitic stainless steel pipe for high-temperature and general corrosive service. Seamless pipe has no welding at any stage. It is hot finished or cold finished (cold drawn), then solution annealed at 1040 C minimum and rapidly cooled. 316L is the low-carbon version of 316, so it resists sensitisation. It is used in heavy welded sections (about 5 mm and over) without post-weld annealing.

Grade and Equivalents

Chemistry (%): C 0.035 max, Mn 2.00 max, P 0.045 max, S 0.030 max, Si 1.00 max, Cr 16.0-18.0, Ni 10.0-14.0, Mo 2.0-3.0.
Mechanical (min): tensile 485 MPa (70 ksi), yield 170 MPa (25 ksi), elongation in 50 mm 35% longitudinal, 25% transverse.

Molybdenum gives the same pitting and crevice resistance in chlorides as 316. The grade cannot be hardened by heat treatment and has excellent toughness down to cryogenic temperatures. Its scaling limit in air is 925 C for continuous service and 870 C for intermittent service. This is not a pressure-design limit.

Sizes and Dimensions

Dimensions are to ASME B36.19M: NPS 1/2 to NPS 24 (OD 21.3 mm to 610 mm) in Sch 10S, 40S and 80S. The standard also lists Sch 5S. A312 allows other dimensions, and heavier walls such as Sch 160 and XXS are taken from ASME B36.10M. Ends are plain (PE). Under A312, unless otherwise specified, NPS 1/8 to NPS 8 come in lengths up to 7.3 m (permissible range 4.6-7.3 m). Cut lengths can be ordered. The full size table (OD, wall and kg/m for each schedule) is in the listing images. Common Sch 40S sizes:

Standards and Tests

Tests required by A312:

• Tension test, transverse or longitudinal: 1 per lot of up to 100 pipes, 2 for larger lots
• Flattening test on 5% of pipe from each heat-treated lot
• Hydrostatic test or nondestructive electric test on each pipe
• Chemical analysis to A312 Table 1

These tests are done only when ordered: intergranular corrosion test to ASTM A262 Practice E (A312 Supplementary Requirement S7), PMI, ultrasonic examination (UT) and third-party inspection to EN 10204 3.2.

Applications and Industries

• Heavy-gauge welded chemical process piping
• Cryogenic piping
• Pharmaceutical and food process lines
• Heat exchangers

Industries: chemical and petrochemical, pharmaceutical, food and beverage, LNG and cryogenic.

Supply from Allied Metal & Tubes

Allied Metal & Tubes, Khetwadi, Mumbai, Maharashtra, was established in 1993. The company is a stockist and dealer of stainless steel pipes, tubes, sheets and plates, carbon steel seamless pipes, alloy steel pipes and other ferrous and non-ferrous metals. It is MSME registered and ISO 9001:2015 certified, and its main domestic market is all of India. Send your size, schedule, length and quantity for a quote.

FAQ

What is the difference between 316 and 316L pipe?
316L has C 0.035% max and a lower minimum strength: 485/170 MPa, against 515/205 MPa for 316. Dual-certified 316/316L pipe meets both grades, but it may be unacceptable for high-temperature service.

How do I calculate SS 316L pipe weight?
The Indian trade formula is kg/m = (OD - WT) x WT x 0.02491, with OD and WT in mm. This is a 304 factor, so for 316L the result is about 0.6% low. The table weights use 7980 kg/m.

Which test certificate comes with the pipe?
EN 10204 3.1 mill test certificates are the usual supply basis. A 3.1 certificate covers only the tests it reports, so IGC, PMI, UT and third-party 3.2 inspection must be specified on the order.