Technical Threads frequently receives requests for 304L and 316L fasteners. Often, these are referred to as a “specification”. Just like the straight grades of 304 and 316, the “L” isn’t a full specification– it’s just a more specific material. 304L fasteners and 316L fasteners can be provided to either ASTM A193/4, ASTM A320 for low temp service or ASTM F593/4.

The “L” in both 304L and 316L refers to low-carbon bolts. The carbon content is restricted to .03%, less than half the normal maximum that 304 and 316 can have.

We inventory a limited amount of “L” grade bolting in hex cap screws, studs and both finished and heavy pattern nuts. The material can be provided with certs calling out the “L” grade. If the project calls for a “L” stamp on the material, that can be provided.

The 304L/316L is used in the following environments and applications.
*Most commonly, to make chemical environments with washdown that requires 316L pipe, valves and fittings.
*In applications that require the fasteners to be welded for security after assembly (low carbon means the bolts are softer– it also means that it is easier to weld on).

Please call us today @ 317-215-4718 to discuss your low carbon stainless steel fastener application.