Execution standard reference

ASME B18.2.1 Hex cap screws — inch series (Table 6 profile)

ASME B18.2.1 Table 6 hex cap screw dimensional profile, inch series.

boltEdition: 2012Current standardDimensions available

Dimensional reference

Shows dimensions already stored in the standard library. Missing values are not filled automatically.

ASME B18.2.1 dimensional reference

Hex cap screws — inch series (Table 6 profile)

Standardized drawing

dThread size	nominalDiameterInd · Basic Major Diameter (in)	tpiTPI · Threads Per Inch	threadSeriesThread Series	threadClassThread Class	dMaxd max · Body Diameter Max (in)	dMind min · Body Diameter Min (in)	sAcross flats · mm	sMins · Width Across Flats (min) (in)	eAcross corners · mm	eMaxe · Width Across Corners (max) (in)	kHead height · mm	kMink · Head Height (min) (in)	wrenchingHeightMinJ · Wrenching Height (min) (in)	threadLengthLe6LT · Nominal Thread Length (L≤6 in) (in)	threadLengthGt6LT · Nominal Thread Length (L>6 in) (in)
1/4-20 UNC	0.25	20	UNC	2A	0.25	0.245	0.438	0.428	0.488	0.505	0.163	0.15	0.106	0.75	1
1/4-28 UNF	0.25	28	UNF	2A	0.25	0.245	0.438	0.428	0.488	0.505	0.163	0.15	0.106	0.75	1
5/16-18 UNC	0.3125	18	UNC	2A	0.3125	0.306	0.5	0.489	0.557	0.577	0.211	0.195	0.14	0.875	1.125
5/16-24 UNF	0.3125	24	UNF	2A	0.3125	0.306	0.5	0.489	0.557	0.577	0.211	0.195	0.14	0.875	1.125
3/8-16 UNC	0.375	16	UNC	2A	0.375	0.369	0.562	0.551	0.628	0.65	0.243	0.226	0.16	1	1.25
3/8-24 UNF	0.375	24	UNF	2A	0.375	0.369	0.562	0.551	0.628	0.65	0.243	0.226	0.16	1	1.25
7/16-14 UNC	0.4375	14	UNC	2A	0.4375	0.4305	0.625	0.612	0.698	0.722	0.291	0.272	0.195	1.125	1.375
7/16-20 UNF	0.4375	20	UNF	2A	0.4375	0.4305	0.625	0.612	0.698	0.722	0.291	0.272	0.195	1.125	1.375
1/2-13 UNC	0.5	13	UNC	2A	0.5	0.493	0.75	0.736	0.84	0.866	0.323	0.302	0.215	1.25	1.5
1/2-20 UNF	0.5	20	UNF	2A	0.5	0.493	0.75	0.736	0.84	0.866	0.323	0.302	0.215	1.25	1.5
9/16-12 UNC	0.5625	12	UNC	2A	0.5625	0.5545	0.812	0.798	0.91	0.938	0.371	0.348	0.25	1.375	1.625
9/16-18 UNF	0.5625	18	UNF	2A	0.5625	0.5545	0.812	0.798	0.91	0.938	0.371	0.348	0.25	1.375	1.625
5/8-11 UNC	0.625	11	UNC	2A	0.625	0.617	0.938	0.922	1.051	1.083	0.403	0.378	0.269	1.5	1.75
5/8-18 UNF	0.625	18	UNF	2A	0.625	0.617	0.938	0.922	1.051	1.083	0.403	0.378	0.269	1.5	1.75
3/4-10 UNC	0.75	10	UNC	2A	0.75	0.741	1.125	1.1	1.254	1.299	0.483	0.455	0.324	1.75	2
3/4-16 UNF	0.75	16	UNF	2A	0.75	0.741	1.125	1.1	1.254	1.299	0.483	0.455	0.324	1.75	2
7/8-9 UNC	0.875	9	UNC	2A	0.875	0.866	1.312	1.285	1.465	1.516	0.563	0.531	0.378	2	2.25
7/8-14 UNF	0.875	14	UNF	2A	0.875	0.866	1.312	1.285	1.465	1.516	0.563	0.531	0.378	2	2.25
1-8 UNC	1	8	UNC	2A	1	0.99	1.5	1.469	1.675	1.732	0.627	0.591	0.416	2.25	2.5
1-12 UNF	1	12	UNF	2A	1	0.99	1.5	1.469	1.675	1.732	0.627	0.591	0.416	2.25	2.5
1-1/8-7 UNC	1.125	7	UNC	2A	1.125	1.114	1.688	1.631	1.859	1.949	0.718	0.658	0.461	2.5	2.75
1-1/8-12 UNF	1.125	12	UNF	2A	1.125	1.114	1.688	1.631	1.859	1.949	0.718	0.658	0.461	2.5	2.75
1-1/4-7 UNC	1.25	7	UNC	2A	1.25	1.239	1.875	1.812	2.066	2.165	0.813	0.749	0.53	2.75	3
1-1/4-12 UNF	1.25	12	UNF	2A	1.25	1.239	1.875	1.812	2.066	2.165	0.813	0.749	0.53	2.75	3
1-3/8-6 UNC	1.375	6	UNC	2A	1.375	1.363	2.062	1.994	2.273	2.382	0.878	0.81	0.569	3	3.25
1-3/8-12 UNF	1.375	12	UNF	2A	1.375	1.363	2.062	1.994	2.273	2.382	0.878	0.81	0.569	3	3.25
1-1/2-6 UNC	1.5	6	UNC	2A	1.5	1.488	2.25	2.175	2.48	2.598	0.974	0.902	0.64	3.25	3.5
1-1/2-12 UNF	1.5	12	UNF	2A	1.5	1.488	2.25	2.175	2.48	2.598	0.974	0.902	0.64	3.25	3.5

d1/4-20 UNC

nominalDiameterIn0.25

tpi20

threadSeriesUNC

More dimensions

threadClass2A

dMax0.25

dMin0.245

s · mm0.438

sMin0.428

e · mm0.488

eMax0.505

k · mm0.163

kMin0.15

wrenchingHeightMin0.106

threadLengthLe60.75

threadLengthGt61

d1/4-28 UNF

nominalDiameterIn0.25

tpi28

threadSeriesUNF

More dimensions

threadClass2A

dMax0.25

dMin0.245

s · mm0.438

sMin0.428

e · mm0.488

eMax0.505

k · mm0.163

kMin0.15

wrenchingHeightMin0.106

threadLengthLe60.75

threadLengthGt61

d5/16-18 UNC

nominalDiameterIn0.3125

tpi18

threadSeriesUNC

More dimensions

threadClass2A

dMax0.3125

dMin0.306

s · mm0.5

sMin0.489

e · mm0.557

eMax0.577

k · mm0.211

kMin0.195

wrenchingHeightMin0.14

threadLengthLe60.875

threadLengthGt61.125

d5/16-24 UNF

nominalDiameterIn0.3125

tpi24

threadSeriesUNF

More dimensions

threadClass2A

dMax0.3125

dMin0.306

s · mm0.5

sMin0.489

e · mm0.557

eMax0.577

k · mm0.211

kMin0.195

wrenchingHeightMin0.14

threadLengthLe60.875

threadLengthGt61.125

d3/8-16 UNC

nominalDiameterIn0.375

tpi16

threadSeriesUNC

More dimensions

threadClass2A

dMax0.375

dMin0.369

s · mm0.562

sMin0.551

e · mm0.628

eMax0.65

k · mm0.243

kMin0.226

wrenchingHeightMin0.16

threadLengthLe61

threadLengthGt61.25

d3/8-24 UNF

nominalDiameterIn0.375

tpi24

threadSeriesUNF

More dimensions

threadClass2A

dMax0.375

dMin0.369

s · mm0.562

sMin0.551

e · mm0.628

eMax0.65

k · mm0.243

kMin0.226

wrenchingHeightMin0.16

threadLengthLe61

threadLengthGt61.25

用于英制六角头螺钉选型、产品建立、TDS和报价。材料性能仍须按订单指定的ASTM材料标准及真实文件确认。

Available products

Hexagon Head Bolt, SAE J429 Grade 5, UNC

Carbon Steel

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