Proof Loads for Screws

Proof loads – ISO metric coarse pitch thread:

Thread1) d	Nominal stress area As,nom [mm²]	Proof load Fp (As,nom × Sp,nom 4)) [N]
Thread1) d	Nominal stress area As,nom [mm²]	4.6	4.8	5.6	5.8	6.8	8.8	9.8	10.9	12.9/12.9
M3	5.03	1130	1560	1410	1910	2210	2920	3270	4180	4880
M3.5	6.78	1530	2100	1900	2580	2980	3940	4410	5630	6580
M4	8.78	1980	2720	2460	3340	3860	5100	5710	7290	8520
M5	14.2	3200	4400	3980	5400	6250	8230	9230	11800	13800
M6	20.1	4520	6230	5630	7640	8840	11600	13100	16700	19500
M7	28.9	6500	8960	8090	11000	12700	16800	18800	24000	28000
M8	36.6	82402)	11400	102002)	13900	16100	212002)	23800	304002)	35500
M10	58.0	130002)	18000	162002)	22000	25500	337002)	37700	481002)	56300
M12	84.3	19000	26100	23600	32000	37100	489003)	54800	70000	81800
M14	115	25900	35600	32200	43700	50600	667003)	74800	95500	112000
M16	157	35300	48700	44000	59700	69100	910003)	102000	130000	152000
M18	192	43200	59500	53800	73000	84500	115000	–	159000	186000
M20	245	55100	76000	68600	93100	108000	147000	–	203000	238000
M22	303	68200	93900	84800	115000	133000	182000	–	252000	294000
M24	353	79400	109000	98800	134000	155000	212000	–	293000	342000
M27	459	103000	142000	128000	174000	202000	275000	–	381000	445000
M30	561	126000	174000	157000	213000	247000	337000	–	466000	544000
M33	694	156000	215000	194000	264000	305000	416000	–	576000	673000
M36	817	184000	253000	229000	310000	359000	490000	–	678000	792000
M39	976	220000	303000	273000	371000	429000	586000	–	810000	947000

1 Where no thread pitch is indicated in a thread designation, coarse pitch is specified.
2 For fasteners with thread tolerance 6az per ISO 965-4, subject to hot dip galvanizing, reduced values per ISO 10684.
3 For structural bolting 50 700 N (for M12), 68 800 N (for M14) and 94 500 N (for M16).
4 Proof load stress and relation to non-proportional elongation, see mechanical and physical properties of screws, No. 5

Proof loads – ISO metric Fine pitch thread:

Thread d × P	Nominal stress area As,nom [mm²]	Proof load Fp (As,nom × Sp,nom) [N]
Thread d × P	Nominal stress area As,nom [mm²]	4.6	4.8	5.6	5.8	6.8	8.8	9.8	10.9	12.9/12.9
M8×1	39.2	8820	12200	11000	14900	17200	22700	25500	32500	38000
M10×1.25	61.2	13800	19000	17100	23300	26900	35500	39800	50800	59400
M10×1	64.5	14500	20000	18100	24500	28400	37400	41900	53500	62700
M12×1.25	92.1	20700	28600	25800	35000	40500	53400	59900	76400	89300
M12×1.5	88.1	19800	27300	24700	33500	38800	51100	57300	73100	85500
M14×1.5	125	28100	38800	35000	47500	55000	72500	81200	104000	121000
M16×1.5	167	37600	51800	46800	63500	73500	96900	109000	139000	162000
M18×1.5	216	48600	67000	60500	82100	95000	130000	–	179000	210000
M20×1.5	272	61200	84300	76200	103000	120000	163000	–	226000	264000
M22×1.5	333	74900	103000	93200	126000	146000	200000	–	276000	323000
M24×1.2	384	86400	119000	108000	146000	169000	230000	–	319000	372000
M27×2	496	112000	154000	139000	188000	218000	298000	–	412000	481000
M30×2	621	140000	192000	174000	236000	273000	373000	–	515000	602000
M33×2	761	171000	236000	213000	289000	335000	457000	–	632000	738000
M36×3	865	195000	268000	242000	329000	381000	519000	–	718000	839000
M39×3	1030	232000	319000	288000	391000	453000	618000	–	855000	999000