Carbon Steel


The standards of A694 are more rigorous than the more common SA105N and SA350LF2 grades, providing more robust specifications for high-pressure fluid transmission in oil and gas piping systems. The increased demands on the physical properties of the steel create a stronger metal throughout the pressure range, from low to high temperature services.

Each grade in the A694 specification is assigned a number correlating to the minimum yield strength (in ksi units) required for that grade; GradeF52 for example requires a minimum Yield Strength of 52 ksi.


This is a mild Carbon Steel that is not only one of the most common of the Carbon steels, but also one of the most common steels in the world. It is hard, not brittle or ductile, and has a low price point. SA105N is very common throughout many industries, and is even used with stainless Steel piping systems with the aid oflap joint End Rings

We stock large diameter (18” – 42”) SLIP-ON, Lap Joint, Weld Neck, and Blind Flanges in SA105N, in class 150 and 300, and can also source a variety of sizes and classes for longer lead times, from 12” to 60”.

SA350 LF2

This is a grade of Carbon Steel intended primarily for low-temperature service and requires notch toughness testing. Very similar to SA105N, this material is used in more industrial applications such as the oil and gas industries.

We can supply large diameter Flanges of all types in SA350LF2, from 18” to 60”, in a wide variety of pressure classes.

Chemical composition
A350 LF2Si0.15~0.3
Mechanical properties
Tensile Strength, ksi [MPa]70-95 [485-655]
Yield Strength, Min., ksi [MPa]36 [250]
A350LF2 CL1Elongation - 2 in. [50mm] / 4D, Min., %30 / 22
Reduction of Area, Min., %40.00
Brinell Hardness, max187