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Min. ultimate tensile strength and yield strength – UNC threads

Min. ultimate tensile strength, N, UNC thread
Steel – UNC thread

Thread	Number of threads per inch	Nominal stress area mm²	Property class
Thread	Number of threads per inch	Nominal stress area mm²	4.8 415 N/mm²	5.8 510 N/mm²	8.8 827 N/mm²	10.9 1034 N/mm²	12.9 1239 N/mm²
1/4	20	20.5	8500	10450	16950	21200	25400
5/16	18	33.8	14000	17250	27950	34950	41900
3/8	16	50	20700	25500	41350	51700	62000
7/16	14	68.6	28400	34900	56750	70900	85100
1/2	13	91.5	37900	46700	75700	94600	113500
9/16	12	117	48400	59700	96800	121000	145100
5/8	11	146	60400	74400	120700	151000	181000
3/4	10	216	89400	110200	178600	223300	267800
7/8	9	298	123400	152000	246400	308100	369500
1	8	391	161900	199400	323400	404300	484800
1 1/8	7	492	203700	250900	406900	508700	610100
1 1/4	7	625	258700	318700	516900	646200	775000
1 3/8	6	745	308400	380000	616100	770030	923800
1 1/2	6	907	375500	462600	750100	937800	1124700

Nominal yield strength, N, UNC thread

Steel – UNC thread

Thread	Number of threads per inch	Nominal stress area mm²	Property class
Thread	Number of threads per inch	Nominal stress area mm²	4.8 248 N/mm²	5.8 393 N/mm²	8.8 634 N/mm²	10.9 896 N/mm²	12.9 1117 N/mm²
1/4	20	20.5	5080	8060	13000	18400	12900
5/16	18	33.8	8380	13300	21400	30300	37800
3/8	16	50	12400	19700	31700	44800	55900
7/16	14	68.6	17000	27000	43500	61500	76600
1/2	13	91.5	22700	36000	58000	82000	102000
9/16	12	117	29000	46000	74200	105000	131000
5/8	11	146	36200	57400	92600	131000	163000
3/4	10	216	53600	84900	137000	194000	241000
7/8	9	298	73900	11700	189000	267000	333000
1	8	391	97000	154000	248000	350000	437000
1 1/8	7	492	122000	193000	312000	441000	550000
1 1/4	7	625	155000	246000	396000	560000	698000
1 3/8	6	745	185000	293000	472000	667500	832000
1 1/2	6	907	225000	356000	575000	813000	10130000