NEDRA Rulebook Tables

Table 1: Simple Two-Bolt Strap Hold-down on Flat Surface
			Grade 1			Grade 5			Grade 8
Nominal Size (inch)	Tensile Area (inch^2)	Stress Concentration Factor	Strength (ksi)	Load (lbf)	Battery (lb)	Strength (ksi)	Load (lbf)	Battery (lb)	Strength (ksi)	Load (lbf)	Battery (lb)
#8	0.014	3.85	85.0	309.1	15.5	120.0	436.4	21.8
#10	0.0175	3.85	85.0	386.4	19.3	120.0	545.5	27.3
1/4	0.0318	3.85	33	272.6	13.6	85.0	702.1	35.1	120.0	991.2	49.6
5/16	0.0524	3.85	33	449.1	22.5	85.0	1156.9	57.8	120.0	1633.2	81.7
3/8	0.0775	3.85	33	664.3	33.2	85.0	1711.0	85.6	120.0	2415.6	120.8
7/16	0.106	3.85	33	908.6	45.4	85.0	2340.3	117.0	120.0	3303.9	165.2
1/2	0.1419	3.85	33	1216.3	60.8	85.0	3132.9	156.6	120.0	4422.9	221.1
9/16	0.182	3.85	33	1560.0	78.0	85.0	4018.2	200.9	120.0	5672.7	283.6
5/8	0.226	3.85	33	1937.1	96.9	85.0	4989.6	249.5	120.0	7044.2	352.2

Table 2: Maxiumum Battery Weights

Strap Sizes for Grade 1 Bolt Steel 6061-T4 Aluminum

Nominal Bolt Size (inch) Tensile Stress Area (inch^2) Stress Conc. Factor Grade 1 Strengh (ksi) Max Load (lbf) Head Circum. (inch) Max Force per Inch Strap Str (ksi) Strap Thickness (inch) Min Strap Width (inch) Strap Cross Section (inch^2) Strap Str (ksi) Strap Thickness (inch) Min Strap Width (inch) Strap Cross Section (inch^2)

#8 0.014 3.85 33 120.0 0.901 133.1587 33 0.0155 0.936 0.01454 20 0.0256 0.936 0.024

#10 0.0175 3.85 33 150.0 1.04876 143.026 33 0.0167 1.0896 0.018 20 0.0275 1.0896 0.03

1/4 0.0318 3.85 33 272.6 1.37 198.41 33 0.0231 1.427 0.033 20 0.038 1.427 0.0545

5/16 0.0524 3.85 33 449.1 1.57 286.078 33 0.033 1.631 0.054 20 0.055 1.631 0.0898

3/8 0.0775 3.85 33 664.3 1.766 376.099 33 0.0439 1.835 0.0805 20 0.0724 1.835 0.133

7/16 0.106 3.85 33 908.6 1.9625 462.966 33 0.054 2.03896 0.110 20 0.0891 2.03896 0.1817

1/2 0.1419 3.85 33 1216.3 2.355 516.470 33 0.060 2.4468 0.147 20 0.0994 2.447 0.243

9/16 0.182 3.85 33 1560.0 2.55 611.465 33 0.071 2.65 0.189 20 0.1177 2.65 0.312

5/8 0.226 3.85 33 1937.1 2.944 658.053 33 0.07677 3.058 0.2348 20 0.127 3.058 0.387

Strap Sizes for Grade 5 Bolt Steel 6061-T4 Aluminum

Nominal Bolt Size (inch) Tensile Stress Area (inch^2) Stress Conc Factor Grade 5 Strengh (ksi) Max Load (lbf) Head Circum (inch) Max Force per Inch Strap Str (ksi) Strap Thickness (inch) Min Strap Width (inch) Strap Cross Section (inch^2) Strap Str (ksi) Strap Thickness (inch) Min Strap Width (inch) Strap Cross Section (inch^2)

#8 0.014 3.85 85 309.1 0.901 342.985 33 0.040 0.936 0.037 20 0.066 0.936 0.0618

#10 0.0175 3.85 85 386.4 1.04876 368.400 33 0.0430 1.0896 0.0468 20 0.071 1.090 0.077

1/4 0.0318 3.85 85 702.1 1.374 511.067 33 0.0596 1.427 0.085 20 0.0983 1.427 0.140

5/16 0.052 3.85 85 1156.9 1.57 736.868 33 0.0860 1.631 0.140 20 0.142 1.631 0.231

3/8 0.0775 3.85 85 1711.0 1.766 968.741 33 0.113 1.835 0.2074 20 0.186 1.835 0.342

7/16 0.106 3.85 85 2340.3 1.9625 1192.489 33 0.139 2.03896 0.284 20 0.2296 2.03896 0.468

1/2 0.1419 3.85 85 3132.9 2.355 1330.300 33 0.155 2.447 0.379 20 0.256 2.447 0.6266

9/16 0.182 3.85 85 4018.2 2.551 1574.986 33 0.1837 2.650 0.487 20 0.303 2.650 0.804

5/8 0.226 3.85 85 4989.6 2.944 1694.984 33 0.198 3.058 0.6048 20 0.326 3.058 0.998

Strap Sizes for Grade 8 Bolt Steel 6061-T4 Aluminum

Nominal Bolt Size (inch) Tensile Stress Area (inch^2) Stress Conc Factor Grade 8 Strengh (ksi) Max Load (lbf) Head Circum (inch) Max Force per Inch Strap Str (ksi) Strap Thickness (inch) Min Strap Width (inch) Strap Cross Section (inch^2) Strap Str (ksi) Strap Thickness (inch) Min Strap Width (inch) Strap Cross Section (inch^2)

#8 0.014 3.85 120 436.4 0.90118 484.213627 33 0.0565 0.936 0.0529 20 0.0932 0.9363 0.08727

#10 0.0175 3.85 120 545.5 1.0488 520.0947 33 0.0607 1.0896 0.066 20 0.100 1.0896 0.1091

1/4 0.0318 3.85 120 991.2 1.374 721.5060 33 0.084 1.427 0.120 20 0.1389 1.427 0.198

5/16 0.0524 3.85 120 1633.2 1.57 1040.285 33 0.121 1.631 0.198 20 0.200 1.631 0.3266

3/8 0.0775 3.85 120 2415.6 1.766 1367.634 33 0.1596 1.835 0.293 20 0.263 1.835 0.483

7/16 0.106 3.85 120 3303.9 1.9625 1683.514 33 0.196 2.039 0.400 20 0.324 2.039 0.661

1/2 0.1419 3.85 120 4422.9 2.355 1878.071 33 0.219 2.447 0.536 20 0.362 2.447 0.885

9/16 0.182 3.85 120 5672.7 2.551 2223.509 33 0.259 2.651 0.688 20 0.428 2.651 1.135

5/8 0.226 3.85 120 7044.2 2.944 2392.9192 33 0.2792 3.058 0.854 20 0.4606 3.058 1.409

Table 2: Maxiumum Battery Weights
Strap Sizes for Grade 1 Bolt	Steel	6061-T4 Aluminum
Nominal Bolt Size (inch)	Tensile Stress Area (inch^2)	Stress Conc. Factor	Grade 1 Strengh (ksi)	Max Load (lbf)	Head Circum. (inch)	Max Force per Inch	Strap Str (ksi)	Strap Thickness (inch)	Min Strap Width (inch)	Strap Cross Section (inch^2)	Strap Str (ksi)	Strap Thickness (inch)	Min Strap Width (inch)	Strap Cross Section (inch^2)
#8	0.014	3.85	33	120.0	0.901	133.1587	33	0.0155	0.936	0.01454	20	0.0256	0.936	0.024
#10	0.0175	3.85	33	150.0	1.04876	143.026	33	0.0167	1.0896	0.018	20	0.0275	1.0896	0.03
1/4	0.0318	3.85	33	272.6	1.37	198.41	33	0.0231	1.427	0.033	20	0.038	1.427	0.0545
5/16	0.0524	3.85	33	449.1	1.57	286.078	33	0.033	1.631	0.054	20	0.055	1.631	0.0898
3/8	0.0775	3.85	33	664.3	1.766	376.099	33	0.0439	1.835	0.0805	20	0.0724	1.835	0.133
7/16	0.106	3.85	33	908.6	1.9625	462.966	33	0.054	2.03896	0.110	20	0.0891	2.03896	0.1817
1/2	0.1419	3.85	33	1216.3	2.355	516.470	33	0.060	2.4468	0.147	20	0.0994	2.447	0.243
9/16	0.182	3.85	33	1560.0	2.55	611.465	33	0.071	2.65	0.189	20	0.1177	2.65	0.312
5/8	0.226	3.85	33	1937.1	2.944	658.053	33	0.07677	3.058	0.2348	20	0.127	3.058	0.387
Strap Sizes for Grade 5 Bolt	Steel	6061-T4 Aluminum
Nominal Bolt Size (inch)	Tensile Stress Area (inch^2)	Stress Conc Factor	Grade 5 Strengh (ksi)	Max Load (lbf)	Head Circum (inch)	Max Force per Inch	Strap Str (ksi)	Strap Thickness (inch)	Min Strap Width (inch)	Strap Cross Section (inch^2)	Strap Str (ksi)	Strap Thickness (inch)	Min Strap Width (inch)	Strap Cross Section (inch^2)
#8	0.014	3.85	85	309.1	0.901	342.985	33	0.040	0.936	0.037	20	0.066	0.936	0.0618
#10	0.0175	3.85	85	386.4	1.04876	368.400	33	0.0430	1.0896	0.0468	20	0.071	1.090	0.077
1/4	0.0318	3.85	85	702.1	1.374	511.067	33	0.0596	1.427	0.085	20	0.0983	1.427	0.140
5/16	0.052	3.85	85	1156.9	1.57	736.868	33	0.0860	1.631	0.140	20	0.142	1.631	0.231
3/8	0.0775	3.85	85	1711.0	1.766	968.741	33	0.113	1.835	0.2074	20	0.186	1.835	0.342
7/16	0.106	3.85	85	2340.3	1.9625	1192.489	33	0.139	2.03896	0.284	20	0.2296	2.03896	0.468
1/2	0.1419	3.85	85	3132.9	2.355	1330.300	33	0.155	2.447	0.379	20	0.256	2.447	0.6266
9/16	0.182	3.85	85	4018.2	2.551	1574.986	33	0.1837	2.650	0.487	20	0.303	2.650	0.804
5/8	0.226	3.85	85	4989.6	2.944	1694.984	33	0.198	3.058	0.6048	20	0.326	3.058	0.998
Strap Sizes for Grade 8 Bolt	Steel	6061-T4 Aluminum
Nominal Bolt Size (inch)	Tensile Stress Area (inch^2)	Stress Conc Factor	Grade 8 Strengh (ksi)	Max Load (lbf)	Head Circum (inch)	Max Force per Inch	Strap Str (ksi)	Strap Thickness (inch)	Min Strap Width (inch)	Strap Cross Section (inch^2)	Strap Str (ksi)	Strap Thickness (inch)	Min Strap Width (inch)	Strap Cross Section (inch^2)
#8	0.014	3.85	120	436.4	0.90118	484.213627	33	0.0565	0.936	0.0529	20	0.0932	0.9363	0.08727
#10	0.0175	3.85	120	545.5	1.0488	520.0947	33	0.0607	1.0896	0.066	20	0.100	1.0896	0.1091
1/4	0.0318	3.85	120	991.2	1.374	721.5060	33	0.084	1.427	0.120	20	0.1389	1.427	0.198
5/16	0.0524	3.85	120	1633.2	1.57	1040.285	33	0.121	1.631	0.198	20	0.200	1.631	0.3266
3/8	0.0775	3.85	120	2415.6	1.766	1367.634	33	0.1596	1.835	0.293	20	0.263	1.835	0.483
7/16	0.106	3.85	120	3303.9	1.9625	1683.514	33	0.196	2.039	0.400	20	0.324	2.039	0.661
1/2	0.1419	3.85	120	4422.9	2.355	1878.071	33	0.219	2.447	0.536	20	0.362	2.447	0.885
9/16	0.182	3.85	120	5672.7	2.551	2223.509	33	0.259	2.651	0.688	20	0.428	2.651	1.135
5/8	0.226	3.85	120	7044.2	2.944	2392.9192	33	0.2792	3.058	0.854	20	0.4606	3.058	1.409

Table 3: Hold-down Bolt Size for Rack or Box-Mounted Box
			Grade 1			Grade 5			Grade 8
Nominal Size (inch)	Tensile Area (inch^2)	Stress Concentration Factor	Strength (ksi)	Load (lbf)	Battery (lb)	Strength (ksi)	Load (lbf)	Battery (lb)	Strength (ksi)	Load (lbf)	Battery (lb)
#8	0.014	3.85	33	120.0	15.0	85.0	309.1	38.6	120.0	436.4	54.5
#10	0.0175	3.85	33	150.0	18.8	85.0	386.4	48.3	120.0	545.5	68.2
1/4	0.0318	3.85	33	272.6	34.1	85.0	702.1	87.8	120.0	991.2	123.9
5/16	0.0524	3.85	33	449.1	56.1	85.0	1156.9	144.6	120.0	1633.2	204.2
3/8	0.0775	3.85	33	664.3	83.0	85.0	1711.0	213.9	120.0	2415.6	301.9
7/16	0.106	3.85	33	908.6	113.6	85.0	2340.3	292.5	120.0	3303.9	413.0
1/2	0.1419	3.85	33	1216.3	152.0	85.0	3132.9	391.6	120.0	4422.9	552.9
9/16	0.182	3.85	33	1560.0	195.0	85.0	4018.2	502.3	120.0	5672.7	709.1
5/8	0.226	3.85	33	1937.1	242.1	85.0	4989.6	623.7	120.0	7044.2	880.5