Chemical Composition Element Specified / Typical Range (wt. %) C ≤0.08 Mn ≤2.00 Si ≤1.00 P ≤0.045 S ≤0.030 Cr 17.0–20.0 Ni 9.0–13.0 Mo — N ≤0.10 Nb+Ta ≥10×C; ≤1.00 Fe Balance

Mechanical Properties Property Minimum / Requirement Tensile Strength, min. 515 MPa Yield Strength, 0.2%, min. 205 MPa Elongation, min. 30% Hardness As required by the applicable fitting specification

Chemical and petrochemical process piping Oil and gas transmission and production systems Power generation and utility piping Food, beverage and pharmaceutical systems Water treatment and desalination Marine and offshore piping

Chemical Composition Element Specified / Typical Range (wt. %) C ≤0.08 Mn ≤2.00 Si ≤1.00 P ≤0.045 S ≤0.030 Cr 17.0–20.0 Ni 9.0–13.0 Mo — N ≤0.10 Nb+Ta ≥10×C; ≤1.00 Fe Balance

Mechanical Properties Property Minimum / Requirement Tensile Strength, min. 515 MPa Yield Strength, 0.2%, min. 205 MPa Elongation, min. 30% Hardness As required by the applicable fitting specification

Chemical and petrochemical process piping Oil and gas transmission and production systems Power generation and utility piping Food, beverage and pharmaceutical systems Water treatment and desalination Marine and offshore piping

347 Stainless Steel Elbow

Grade: 347

Elbow types:

90° Long Radius, 90° Short Radius, 45° Elbow, 180° Return, 3D / 5D Elbow

Standards:

ASME B16.9, EN 10253-4:2025, JIS B2312/2313 etc.

347 is a niobium-stabilized austenitic stainless steel developed for improved resistance to intergranular corrosion after welding and during elevated-temperature service. It has a chemistry broadly related to 304, with niobium added for stabilization. 347 fittings are commonly used in refinery, petrochemical, thermal and chemical-process piping where welded joints experience elevated temperatures or repeated thermal cycles.

Chemical Composition

Element	Specified / Typical Range (wt. %)
C	≤0.08
Mn	≤2.00
Si	≤1.00
P	≤0.045
S	≤0.030
Cr	17.0–20.0
Ni	9.0–13.0
Mo	—
N	≤0.10
Nb+Ta	≥10×C; ≤1.00
Fe	Balance

Mechanical Properties

Property	Minimum / Requirement
Tensile Strength, min.	515 MPa
Yield Strength, 0.2%, min.	205 MPa
Elongation, min.	30%
Hardness	As required by the applicable fitting specification

Chemical and petrochemical process piping
Oil and gas transmission and production systems
Power generation and utility piping
Food, beverage and pharmaceutical systems
Water treatment and desalination
Marine and offshore piping

Introduction

Specification

Chemical Composition

Element	Specified / Typical Range (wt. %)
C	≤0.08
Mn	≤2.00
Si	≤1.00
P	≤0.045
S	≤0.030
Cr	17.0–20.0
Ni	9.0–13.0
Mo	—
N	≤0.10
Nb+Ta	≥10×C; ≤1.00
Fe	Balance

Mechanical

Mechanical Properties

Property	Minimum / Requirement
Tensile Strength, min.	515 MPa
Yield Strength, 0.2%, min.	205 MPa
Elongation, min.	30%
Hardness	As required by the applicable fitting specification