ISO 3506-2

ISO 3506-2 Hex Nuts, High Nuts

Related Specifications

Scope

ISO 3506-2 specification concludes the mechanical and physical properties of nuts, with coarse pitch thread and fine pitch thread, made of corrosion-resistant stainless steels, when tested at the ambient temperature range of 10 °C to 35 °C. iso 3506-2 specifies property classes in relation to austenitic, martensitic, ferritic and duplex (austenitic-ferritic) steel grades for nuts. ISO 3506-2 Specification is applicable to nuts with coarse pitch thread M5 to M39, and fine pitch thread M8×1 to M39×3 with diameter/pitch combinations in accordance with ISO 261 and ISO 262.

Designation

Stainless Steel Grades
A1 to A5 & A8 for Austenitic
C1, C3 & C4 for Martensitic
F1 for Ferritic
D2, D4, D6 & D8 for duplex (austenitic-ferritic)
added by a digit which specifies the range of chemical compositions within this stainless steel group

Property Classes
45 for 450 Mpa Tensile Min
50 for 500 Mpa Tensile Min
60 for 600 Mpa Tensile Min
70 for 700 Mpa Tensile Min
80 for 800 Mpa Tensile Min
100 for 100 Mpa Tensile Min
110 for 110 Mpa Tensile Min

Common Designations

Type Of Steel/Alloy	Grade	Steel Number	Steel Designation	UNS	Trade Name
Resulfurized austenitic	A1	1.4305	X8CrNiS18-9	S30300	303
Resulfurized austenitic	A1	1.4570	X6CrNiCuS18-9-2	–	303Cu
General purpose austenitic	A2L	1.4307	X2CrNi18-9	S30403	304L
	A2L	1.4306	X2CrNi19-11	S30403	304L
	A2L	1.4311	X2CrNiN18-9	S30453	304LN
	A2	1.4301	X5CrNi18-10	S30400	304
	A2	1.4567	X3CrNiCu18-9-4	S30430	304Cu
	A2	1.4560	X3CrNiCu19-9-2	–	304Cu
	A2	1.4303	X4CrNi18-12	S30500	305
	A3	1.455	X6CrNiNb18-10	S34700	347
	A3	1.4541	X6CrNiTi18-10	S32100	321
	–	1.4615	X3CrMnNiCu15-8-5-3	–	201Cu
	–	1.4310	X10CrNi18-8	S30100	301
Molybdenum containing austenitic	A4	1.4401	X5CrNiMo17-12-2	S31600	316
	A4L	1.4404	X2CrNiMo17-12-2	S31603	316L
	A4L	1.4406	X2CrNiMoN17-11-2	S31653	316LN
	A4L	1.4432	X2CrNiMo17-12-3	S31603	316L
	A4L	1.4435	X2CrNiMo18-14-3	S31603	316L
	A4	1.4436	X3CrNiMo17-13-3	S31600	316
	A4	1.4578	X3CrNiCuMo17-11-3-2	–	–
	A5	1.4571	X6CrNiMoTi17-12-2	S31635	316Ti
High molybdenum super-austenitic	A8	1.4478	X2NiCrMoN25-21-7	N08367	AL-6XN
	A8	1.4529	X1NiCrMoCuN25-20-7	N08926	926
	A8	1.4547	X1CrNiMoCuN20-18-7	S31254	F44
Highly alloyed austenitic for special purposes	S	1.4986	X7CrNiMoBNb16-16	–	–
	–	1.4539	X1NiCrMoCu25-20-5	N08904	904L
	–	1.4841	X15CrNiSi25-21	S31400	314
	–	1.4828	X15CrNiSi20-12	–	309
	–	1.4845	X8CrNi25-21	S31008	310S
High manganese super-austenitic	–	1.4020	X13CrMnNiN18-13-2	S24100	XM28
High manganese super-austenitic	–	1.4378	X6CrMnNiN18-13-3	S24000	XM29
General purpose martensitic	C1	1.4006	X12Cr13	S41000	410
	C1	1.4000	X6Cr13	S41008	410S
	C1, CH0	1.4021	X20Cr13	S42000	420
	C1, CH1	1.4028	X30Cr13	S42000	420
	C1	1.4034	X46Cr13	S42000	420
	–	1.4003	X2CrNi12	S41003	410L
High Chromium Martensitic	–	1.4542	X5CrNiCuNb16-4	S17400	17-4PH
	–	1.4418	X4CrNiMo16-5-1	–	SS2387
	–	1.4122	X39CrMo17-1	–	–
Resulfurised martensitic	C4	1.4005	X12CrS13	S41600	416
Resulfurised martensitic	C4	1.4029	X29CrS13	S42020	420F
Ferritic	F1	1.4016	X6Cr17	S43000	430
	F1	1.4511	X3CrNb17	–	430Nb
	F1	1.4113	X6CrMo17-1	S43400	434
	F1	1.4526	X6CrMoNb17-1	S43600	436
	F1	1.4509	X2CrTiNb18	S43940	441
	F1	1.4521	X2CrMoTi18-2	S44400	444
Resulfurised ferritic	–	1.4004	X7CrS17	S43020	430F
Resulfurised ferritic	–	1.4104	X14CrMoS17	S43020	430F
Duplex	D2	1.4482	X2CrMnNiMoN21-5-3	S32001	2001
	D2	1.4362	X2CrNiN23-4	S32304	2304
	D4	1.4162	X2CrMnNiN21-5-1	S32101	2101
	D4	1.4062	X2CrNiN22-2	S32202	2202
	D6	1.4462	X2CrNiMoN22-5-3	S31803, S32205	31803, 2205
	D6	1.4481	X2CrNiMoN25-7-3	S31260	SUS329J4L
	D8	1.4410	X2CrNiMoN25-7-4	S32750	2507
	D8	1.4501	X2CrNiMoCuWN25-7-4	S32760	Zeron 100
	D8	1.4507	X2CrNiMoCuN25-6-3	S32520	Ferralium

ISO 3506-2 Property class combination of nuts to bolts, screws and studs

Property class of bolts, screws and studs	Minimum property class of the mating nuts
Property class of bolts, screws and studs	Regular and high nuts (style 1 and style 2)	Thin nuts (style 0)
45	45	22
50	50	25
60	60	30
70	70	35
80	80	40
100	100	50
110	110	55

Chemical Requirements

Stainless steel grade		Chemical composition ^a (cast analysis, mass fraction in %) ^b										Other elements and notes
Stainless steel grade		C	Si	Mn	P	S	Cr	Mo	Ni	Cu	N	Other elements and notes
Austenitic	A1	0,12	1,00	6,5	20	0,15 to 0,35	16,0 to 19,0	0,70	5,0 to 10,0	1,75 to 2,25	–	^c,d,e
	A2	0,10	1,00	2,00	50	30	15,0 to 20,0	– ^f	8,0 to 19,0	4,0	–	^g,h
	A3	0,08	1,00	2,00	45	30	17,0 to 19,0	– ^f	9,0 to 12,0	1,00	–	5C ≤ Ti ≤ 0,80 and/or 10C ≤ Nb ≤ 1,00
	A4	0,08	1,00	2,00	45	30	16,0 to 18,5	2,00 to 3,00	10,0 to 15,0	4,0	–	^h,i
	A5	0,08	1,00	2,00	45	30	16,0 to 18,5	2,00 to 3,00	10,5 to 14,0	1,00	–	5C ≤ Ti ≤ 0,80 and/or 10C ≤ Nb ≤ 1,00 ⁱ
	A8	30	1,00	2,00	40	30	19,0 to 22,0	6,0 to 7,0	17,5 to 26,0	1,50	–	–
Martensitic	C1	0,09 to 0,15	1,00	1,00	50	30	11,5 to 14,0	–	1,00	–	–	ⁱ
	C3	0,17 to 0,25	1,00	1,00	40	30	16,0 to 18,0	–	1,50 to 2,50	–	–	–
	C4	0,08 to 0,15	1,00	1,50	60	0,15 to 0,35	12,0 to 14,0	0,60	1,00	–	–	^c,i
Ferritic	F1	0,08	1,00	1,00	40	30	15,0 to 18,0	– ^f	1,00	–	–	^j
Duplex	D2	40	1,00	6,0	40	30	19,0 to 24,0	0,10 to 1,00	1,50 to 5,5	3,00	0,05 to 0,20	Cr+3,3Mo + 16N ≤ 24,0 ^k
	D4	40	1,00	6,0	40	30	21,0 to 25,0	0,10 to 2,00	1,00 to 5,5	3,00	0,05 to 0,30	24,0 < Cr+3,3Mo + 16N ^k
	D6	30	1,00	2,00	40	15	21,0 to 23,0	2,50 to 3,5	4,5 to 6,5	–	0,08 to 0,35	–
	D8	30	1,00	2,00	35	15	24,0 to 26,0	3,00 to 4,5	6,0 to 8,0	2,50	0,20 to 0,35	W ≤ 1,00
^a According to material standards, values are maximum unless otherwise indicated and the number of digits shown is in accordance with usual rules; see e.g. EN 10088 (all parts). ^b In case of dispute, product analysis applies. ^c Selenium can be used to replace sulphur; however, restrictions may apply to its use. ^d If the nickel content is below 8,0 %, the minimum manganese content shall be 5,0 %. ^e There is no minimum limit to the copper content provided that the nickel content is greater than 8,0 %. ^f Molybdenum may be present at the discretion of the manufacturer. However, if for some applications limiting of the molybdenum content is essential, this shall be stated at the time of ordering by the purchaser. ^g If the chromium content is below 17,0 %, the minimum nickel content should be 12,0 %. ^h For austenitic stainless steels having a maximum carbon content of 0,030 %, nitrogen may be present but shall not exceed 0,22 %. ⁱ At the discretion of the manufacturer the carbon content may be higher as necessary in order to obtain the specified mechanical properties for larger diameters, but shall not exceed 0,12 % for austenitic steels. ^j Titanium and/or niobium may be included to improve corrosion resistance. ^k This formula is used solely for the purpose of classifying duplex steels in accordance with this document (it is not intended to be used as a selection criterion for corrosion resistance)

Mechanical Requirements

Mechanical properties (Austenitic and Duplex Steel)

Stainless steel grade		Regular nuts and high nuts (style 1 and style 2)		Thin nuts (style 0)
Stainless steel grade		Property class designation and symbol	Stress under proof load ^a S_p MPa	Property class designation and symbol	Stress under proof load ^b S_p MPa
Austenitic	A1 A2 A3	50	500	25	250
		70	700	35	350
		80	800	40	400
	A4 A5	50	500	25	250
		70	700	35	350
		80	800	40	400
		100	1000	50	500
	A8	70	700	35	350
		80	800	40	400
		100	1000	50	500
Duplex	D2 D4 D6 D8	70	700	35	350
		80	800	40	400
		100	1000	50	500
^a Proof load values for regular and high nuts (full loadability) are specified for coarse pitch thread and fine pitch thread. ^b Proof load values for thin nuts (reduced loadability) are specified for coarse pitch thread and fine pitch thread.

Mechanical properties (Martensitic and Ferritic Steel)

Stainless steel grade		Regular nuts and high nuts (style 1 and style 2)		Thin nuts (style 0)		All nuts
		Property class designation and symbol	Stress under proof load ^a S_p	Property class designation and symbol	Stress under proof load ^b S_p	Hardness min. to max.
		Property class designation and symbol	MPa	Property class designation and symbol	MPa	HV	HRC	HBW
Martensitic	C1	50	500	25	250	155 to 220	–	147 to 209
		70	700	35	350	220 to 330	20 to 34	209 to 314
		110 c	1100	055 c	550	350 to 440	36 to 45	–
	C3	80	800	40	400	240 to 340	21 to 35	228 to 323
	C4	50	500	25	250	155 to 220	–	147 to 209
	C4	70	700	35	350	220 to 330	20 to 34	209 to 314
Ferritic	F1^d	45	450	22	225	135 to 220	–	128 to 209
Ferritic	F1^d	60	600	30	300	180 to 285	–	171 to 271
^a Proof load values for regular and high nuts (full loadability) are specified for coarse pitch thread and fine pitch thread. ^b Proof load values for thin nuts (reduced loadability) are specified for coarse pitch thread and fine pitch thread. ^c Hardened and tempered at a minimum tempering temperature of 275 °C. ^d Only for nominal thread diameters D ≤ 24 mm.

Proof load values for regular and high nuts with coarse pitch thread (full loadability)

Thread D×P	Nominal stress area A_s,nom	Proof load, F_pf ^a N
		Austenitic and duplex steels				Martensitic steels				Ferritic steels
		50^b	70	80	100	50	70	80	110	45	60
M5	14,2	7100	9930	11350	14190	7100	9930	11350	15610	6390	8510
M6	20,1	10070	14090	16100	20130	10070	14090	16100	22140	9060	12080
M7	28,9	14430	20210	23090	28860	14430	20210	23090	31750	12990	17320
M8	36,6	18310	25630	29290	36610	18310	25630	29290	40270	16480	21970
M10	58,0	29000	40600	46400	57990	29000	40600	46400	63790	26100	34800
M12	84,3	42140	58990	67420	84270	42140	58990	67420	92700	37920	50560
M14	115	57720	80810	92360	115500	57720	80810	92360	127000	51950	69270
M16	157	78340	109700	125400	156700	78340	109700	125400	172400	70510	94010
M18	192	96240	134800	154000	192500	96240	134800	154000	211800	86620	115500
M20	245	122400	171400	195900	244800	122400	171400	195900	269300	110200	146900
M22	303	151700	212400	242800	303400	151700	212400	242800	333800	136600	182100
M24	353	176300	246800	282100	352600	176300	246800	282100	387800	158700	211600
M27	459	229800	321600	367600	459500	229800	321600	367600	505400	–	–
M30	561	280300	392500	448500	560600	280300	392500	448500	616700	–	–
M33	694	346800	485500	554900	693600	346800	485500	554900	763000	–	–
M36	817	408400	571800	653400	816800	408400	571800	653400	898400	–	–
M39	976	487900	683100	780700	975800	487900	683100	780700	1073400	–	–
^a Proof load values have been calculated from the exact figures of A_s,nom as specified in ISO 3506-1 and rounded to the next upper 10 N up to 100 000 N,and to the next 100 N above. ^b Property class 50 refers to the austenitic grades A1 to A5 only

Proof load values for regular and high nuts with fine pitch thread (full loadability)

Thread D×P	Nominal stress area A_s,nom	Minimum ultimate tensile load, F_mf ^a N
		Austenitic and duplex steels				Martensitic steels				Ferritic steels
		50^b	70	80	100	50	70	80	110	45	60
M8×1	39,2	19590	27420	31340	39170	19590	27420	31340	43090	17630	23510
M10×1,25	61,2	30600	42840	48960	61200	30600	42840	48960	67320	27540	36720
M10×1	64,5	32250	45150	51600	64500	32250	45150	51600	70950	29030	38700
M12×1,5	88,1	44070	61690	70510	88130	44070	61690	70510	96940	39660	52880
M12×1,25	92,1	46040	64460	73660	92080	46040	64460	73660	101300	41440	55250
M14×1,5	125	62280	87190	99640	124600	62280	87190	99640	137100	56050	74730
M16×1,5	167	83630	117100	133800	167300	83630	117100	133800	184000	75270	100400
M18×1,5	216	108200	151400	173000	216300	108200	151400	173000	237900	97310	129800
M20×2	258	129000	180600	206400	258000	129000	180600	206400	283800	116100	154800
M20×1,5	272	135800	190100	217300	271600	135800	190100	217300	298700	122200	163000
M22×1,5	333	166600	233200	266500	333100	166600	233200	266500	366400	149900	199900
M24×2	384	192300	269100	307600	384500	192300	269100	307600	422900	173000	230700
M27×2	496	247900	347100	396600	495800	247900	347100	396600	545400	–	–
M30×2	621	310700	434900	497000	621300	310700	434900	497000	683400	–	–
M33×2	761	380400	532600	608700	760800	380400	532600	608700	836900	–	–
M36×3	865	432500	605500	692000	865000	432500	605500	692000	951500	–	–
M39×3	1030	514200	719900	822800	1028400	514200	719900	822800	1131300	–	–
^a Proof load values have been calculated from the exact figures of A_s,nom as specified in ISO 3506-1 and rounded to the next upper 10 N up to 100 000 N and to the next 100 N above. ^b Property class 50 refers to the austenitic grades A1 to A5 only

Proof load values for thin nuts with coarse pitch thread (reduced loadability)

Thread D×P	Nominal stress area A_s,nom	Proof load, F_pf ^a N
		Austenitic and duplex steels				Martensitic steels				Ferritic steels
		025 ^b	35	40	50	25	35	40	55	22	30
M5	14,2	3550	4970	5680	7100	3550	4970	5680	7810	3200	4260
M6	20,1	5040	7050	8050	10070	5040	7050	8050	11070	4530	6040
M7	28,9	7220	10110	11550	14430	7220	10110	11550	15880	6500	8660
M8	36,6	9160	12820	14650	18310	9160	12820	14650	20140	8240	10990
M10	58,0	14500	20300	23200	29000	14500	20300	23200	31900	13050	17400
M12	84,3	21070	29500	33710	42140	21070	29500	33710	46350	18960	25280
M14	115	28860	40410	46180	57720	28860	40410	46180	63500	25980	34640
M16	157	39170	54840	62670	78340	39170	54840	62670	86170	35260	47010
M18	192	48120	67370	76990	96240	48120	67370	76990	105900	43310	57750
M20	245	61200	85680	97920	122400	61200	85680	97920	134700	55080	73440
M22	303	75850	106200	121400	151700	75850	106200	121400	166900	68270	91020
M24	353	88130	123400	141100	176300	88130	123400	141100	193900	79320	105800
M27	459	114900	160800	183800	229800	114900	160800	183800	252700	–	–
M30	561	140200	196300	224300	280300	140200	196300	224300	308400	–	–
M33	694	173400	242800	277500	346800	173400	242800	277500	381500	–	–
M36	817	204200	285900	326700	408400	204200	285900	326700	449200	–	–
M39	976	244000	341600	390400	487900	244000	341600	390400	536700	–	–
^a Proof load values have been calculated from the exact figures of A_s,nom as specified in ISO 3506-1 and rounded to the next upper 10 N up to 100 000 Nand to the next 100 N above. ^b Property class 025 refers to the austenitic grades A1 to A5 only

Proof load values for thin nuts with fine pitch thread (reduced loadability)

Thread D×P	Nominal stress area A_s,nom	Proof load, F_pf^a N
		Austenitic and duplex steels				Martensitic steels				Ferritic steels
		025^b	35	40	50	25	35	40	55	22	30
M8×1	39,2	9800	13710	15670	19590	9800	13710	15670	21550	8820	11760
M10×1,25	61,2	15300	21420	24480	30600	15300	21420	24480	33660	13770	18360
M10×1	64,5	16130	22580	25800	32250	16130	22580	25800	35480	14520	19350
M12×1,5	88,1	22040	30850	35260	44070	22040	30850	35260	48470	19830	26440
M12×1,25	92,1	23020	32230	36830	46040	23020	32230	36830	50640	20720	27630
M14×1,5	125	31140	43600	49820	62280	31140	43600	49820	68510	28030	37370
M16×1,5	167	41820	58540	66900	83630	41820	58540	66900	91990	37640	50180
M18×1,5	216	54060	75690	86500	108200	54060	75690	86500	119000	48660	64880
M20×2	258	64500	90300	103200	129000	64500	90300	103200	141900	58050	77400
M20×1,5	272	67880	95030	108700	135800	67880	95030	108700	149400	61090	81460
M22×1,5	333	83270	116600	133300	166600	83270	116600	133300	183200	74940	99920
M24×2	384	96110	134600	153800	192300	96110	134600	153800	211500	86500	115400
M27×2	496	124000	173600	198300	247900	124000	173600	198300	272700	–	–
M30×2	621	155400	217500	248500	310700	155400	217500	248500	341700	–	–
M33×2	761	190200	266300	304400	380400	190200	266300	304400	418500	–	–
M36×3	865	216300	302800	346000	432500	216300	302800	346000	475800	–	–
M39×3	1030	257100	360000	411400	514200	257100	360000	411400	565700	–	–
^a Proof load values have been calculated from the exact figures of A_s,nom as specified in ISO 3506-1 and rounded to the next upper 10 N up to 100 000 Nand to the next 100 N above. ^b Property class 025 refers to the austenitic grades A1 to A5 only.

Coating Specifications

Regular and high nuts of grades and property classes C1-70, C3-80 and C4-70, and thin nuts of grades and property classes C1-035, C3-040 and C4-035 shall be quenched and tempered.
Regular and high nuts of grade and property class C1-110 and thin nuts of grade and property class C1- 055 shall be quenched and tempered, with a minimum tempering temperature of 275 °C

Renowned Brands

Nominal Dimensions

Thread D	Width across flats _S	Minimum height of hexagon nuts
		Regular nut (style 1)		High nut (style 2)
		m _min	m _min/D	m _min	m _min/D
M5	8	4,40	0,88	4,80	0,96
M6	10	4,90	0,82	5,40	0,90
M7	11	6,14	0,88	6,84	0,98
M8	13	6,44	0,81	7,14	0,90
M10	16	8,04	0,80	8,94	0,89
M12	18	10,37	0,86	11,57	0,96
M14	21	12,10	0,86	13,40	0,96
M16	24	14,10	0,88	15,70	0,98
M18	27	15,10	0,84	16,90	0,94
M20	30	16,90	0,85	19,00	0,95
M22	34	18,10	0,82	20,50	0,93
M24	36	20,20	0,84	22,60	0,94
M27	41	22,50	0,83	25,40	0,94
M30	46	24,30	0,81	27,30	0,91
M33	50	27,40	0,83	30,90	0,94
M36	55	29,40	0,82	33,10	0,92
M39	60	31,80	0,82	35,90	0,92

Marking

Property class marking (Regular and High nuts)

Property Class	Marking
ISO 3506-2 Class 45	TB 45
ISO 3506-2 Class 50	TB 50
ISO 3506-2 Class 60	TB 60
ISO 3506-2 Class 70	TB 70
ISO 3506-2 Class 80	TB 80
ISO 3506-2 Class 100	TB 100
ISO 3506-2 Class 110	TB 110

Property class marking (Thin nuts)

Property Class	Marking
ISO 3506-2 Class 45	TB 022
ISO 3506-2 Class 50	TB 025
ISO 3506-2 Class 60	TB 030
ISO 3506-2 Class 70	TB 035
ISO 3506-2 Class 80	TB 040
ISO 3506-2 Class 100	TB 050
ISO 3506-2 Class 110	TB 055

Product

Precision Components

Contract Manufacturing

Fastener

Resources

materials

Technical