The Grade 8 Nuts with specified proof load values - coarse thread

The ISO 898-2:2013 Grade 8 specification covers carbon steel nuts ranging from M-6 to M-64 diameter. We use high carbon steel material and high alloy steel raw materials to achieve the required properties of grade 8. There are three popular grades in this standard 8, 10 and 12 which denote material hardness Strength and their respective mechanical properties.

8

Hex Nuts, Heavy Hex Nuts, Jam nuts, Lock Nuts & Thin Hex Nuts

Property class	Material and heat treatment	Chemical composition limit (cast analysis, %)a
		C		P	S	Mn
		min.	max.	max.	max.	min.
8	CARBON STEEL QUENCHED AND TEMPERED	-	0.58	0.048	0.058	0.30

Mechanical or physical property	Vickers hardness HV			Brinell hardness HB			Rockwell hardness HRC
	min.	max.	min.		max.	min.		max.
M5 ≤ D ≤ M16	200	302	190		287	-		30
M16 < D ≤ M39	233	353	221		336	-		36

Thread Size (D)	Pitch (P)	Proof Loada (N)
M12	1.75	74200
M14	2	101200
M16	2	138200
M18	2.5	176600
M20	2.5	225400
M22	2.5	278800
M24	3	324800
M27	3	422300
M30	3.5	516100
M33	3.5	638500
M36	4	751600
M39	4	897900