Duplex Steel Fasteners

Duplex steel fasteners combine the structural features of austenitic and ferritic stainless steels with excellent mechanical strength and superior corrosion resistance. Metracore Alloys is a leading global  Industrial Fasteners manufacturer, engineering and supplying one of the largest inventories of high-performance duplex components for severe environments. We offer a product portfolio of precision machined duplex steel bolts, hefty hex nuts, lug nuts, acorn lug nuts, hardened steel washers and self-tapping steel screws. These solutions are custom designed and provide reliability for highly corrosive operations.

Duplex Steel Fasteners, Duplex Fasteners, Duplex Stainless Steel Fasteners, Duplex Steel Bolts, Duplex Bolts, Duplex Nuts, Duplex Lug Nuts

Our duplex stainless steel fasteners are available in a wide range of dimensional sizes, thread profiles and surface finishes and are designed to address the common industrial difficulties of stress corrosion cracking, cyclic fatigue and surface wear. The controlled microstructural chemistry offers improved tensile strength and localized toughness such that these parts may endure intense structural pressure and high heat loads without yielding. This makes them very well suited for important structural connections and high stress mechanical systems.

Duplex fasteners are extensively employed in maritime, chemical and oil applications where the safety is of prime importance. They withstand extreme salinity pitting and hazardous chloride environments. Metracore Alloys is a trusted Industrial Steel Fastener manufacturer. Precision CNC machining, controlled forging, and calibrated solution annealing remove microstructural flaws and tighten high pressure transport line dimensions.

Duplex Acorn Lug Nuts, Duplex Steel Washers, Duplex Steel Screws, Duplex Fasteners Suppliers, Duplex Steel Fasteners Manufacturers

Material test certificates (MTC) ensure every production lot meets ASTM and ASME quality, safety, and testing standards. Wooden containers, hefty cartons, and anti-corrosion wrapping protect thread geometry during shipping.

Maximize your equipment lifespan today.

Contact Metracore Alloys for a Technical Quote on your next bulk structural project.

Duplex Steel Fasteners Specification

Standard

Standard

ASTM A479 / ASME SA479

Dimensions

Dimensions

DIN 931, 933, 934, 7991, 976, 125, ASME B18.2.1, B18.3

Size

Sizes in Stock

M3 – M56 | 3/6″ to 2″ | Custom Sizes

Process

Standard

IS, ANSI, ASTM DIN, ISO, JIS, GB, ASME, BS, UNI

Types

Threads available

BSF, UNF METRIC, UNC, UNEF, BSW or as required

Class / Process

Threads Configuration

ASME B1.1 2A/3A – 2B/3B Inch Unified Threads and B1.13M 6h-6G Metric Coarse Threads

fasterner-forms

Forms

Hex, Threading, Square, Round as per Gauge Etc.

Flange Thread

Head

Hex, Square, Round, Hex flange, Flat, T-head & Triangular etc.

Types of Duplex Steel Fasteners

bolt

Duplex Steel Bolt

nut

Duplex Steel Nuts

screws

Duplex Steel Screws

washers

Duplex Steel Washers

stud-bolts

Duplex Steel Stud Bolt

Threaded Rod

Duplex Steel Threaded Rod

Anchor Bolt

Duplex Steel Anchor Bolt

hex-bolt

Duplex Steel
Hex Bolt

hex-nut

Duplex Steel
Hex Nut

Reach out to Metracore Alloys for reliable Duplex Steel Fasteners solutions

Technical Details of Duplex Steel Fasteners

Dimensions of Duplex Steel Bolts Fasteners

Nominal Size Of D Diameter Of Body   ASTM A193 Head Thickness   ASTM A193 Flats Acro   ASTM A193 Corners Acro  
  D (MAXIMUM) D (MINIMUM) H (MAXIMUM) H (MINIMUM) F (MAXIMUM) F (MINIMUM) C (MAXIMUM) C (MINIMUM)
m10 10.00 9.78 6.63 6.17 17.00 15.73 18.48 17.77
m12 12.00 11.73 7.76 4.24 19.00 17.73 20.78 20.03
m14 14.00 13.73 9.09 8.51 22.00 20.67 24.25 23.35
m16 16.00 15.73 10.32 9.68 24.00 23.67 27.71 26.75
m20 20.00 19.67 12.88 12.12 30.00 29.16 34.64 32.95
m24 24.00 23.67 15.44 14.56 36.00 35.00 41.57 39.55
m30 30.00 29.67 19.48 17.92 46.00 45.00 53.12 50.85
m36 36.00 35.61 23.38 21.63 55.00 53.80 63.51 60.79
m42 42.00 41.38 26.97 25.03 65.00 62.90 75.06 71.71
m48 48.00 47.38 31.07 28.93 75.00 72.60 86.60 82.76
m56 56.00 55.26 36.2 33.80 85.00 82.20 98.15 93.71
m64 64.00 63.26 41.32 38.68 95.00 91.80 109.70 104.65
m72 72.00 71.26 46.45 43.55 105.00 101.40 121.24 115.60
m80 80.00 79.26 51.58 48.42 115.00 111.00 132.72 126.54
m90 90.00 89.13 57.74 54.26 130.00 125.50 150.11 143.07
m100 90.00 99.13 63.9 60.10 145.00 140.00 167.43 159.60
Nominal Size Of Thread Diameter F G H
Across Flats
Width
Across Corners
Width
Thickness Row
Basic Maximum Minimum Maximum Minimum Basic Maximum Minimum
1/4 .2500 7/16 .438 .428 .505 .488 7/32 .226 .212
5/16 .3125 1/2 .500 .489 .577 .557 17/64 .273 .258
3/8 .3750 9/16 .562 .551 .650 .628 21/64 .337 .479
7/16 .4375 11/16 .688 .675 .794 .768 3/8 .385 .365
1/2 .5000 3/4 .750 .736 .866 .840 7/16 .448 .427
9/16 .5625 7/8 .875 .861 1.010 .982 31/64 .496 .473
5/8 .6250 15/16 .938 .922 1.083 1.051 35/64 .559 .535
3/4 .7500 1-1/8 1.125 1.088 1.299 1.240 41/64 .665 .617
7/8 .8750 1-5/16 1.312 1.269 1.516 1.447 3/4 .776 .724
1 1.0000 1-1/2 1.500 1.450 1.732 1.653 55/64 .887 .831
1-1/8 1.1250 1-11/16 1.688 1.631 1.949 1.859 31/32 .999 .939
1-3/8 1.3750 2-1/16 2.062 1.994 2.382 2.273 1-11/64 1.206 1.138
1-1/2 1.500 2-1/4 2.250 2.175 2.598 2.480 1-9/32 1.ASTM A194 GR. 8 1.245
1-5/8 1.6250 2-7/16 2.438 2.356 2.815 2.686 1-25/64 1.429 1.353
1-3/4 1.7500 2-5/8 2.625 2.538 3.031 2.893 1-1/2 1.540 1.460
2 2.0000 3 3.000 2.900 3.464 3.306 1-23/32 1.763 1.675
2-1/4 2.2500 3-3/8 3.375 3.263 3.897 3.719 1-15/16 1.986 1.890
2-1/2 2.5000 3-3/4 3.750 3.625 4.330 4.133 2-5/32 2.209 2.105
2-3/4 2.7500 4-1/8 4.125 3.988 4.763 4.546 2-3/8 2.431 2.319
Bolt Size USS SAE
ID (in.) OD (in.) Thickness ID (in.) OD (in.) Thickness
5/32 (#8) 0.188 0.438 .036/.065
1/8 (#6) 0.156 0.375 .036/.065
7/32 (#12) 0.250 0.562 .051/.080
3/16 (#10) 0.250 0.560 .036/.065 0.220 0.500 .036/.065
1/4 (#14) 0.312 0.734 .051/.080 0.281 0.625 .051/.080
3/8 0.438 1.000 .064/.104 0.406 0.812 .051/.080
5/16 0.375 0.875 .064/.104 0.344 0.688 .051/.080
7/16 0.500 1.250 .064/.104 0.469 0.922 .051/.080
9/16 0.625 1.469 .086/.132 0.594 1.156 .074/.121
1/2 0.562 1.375 .086/.132 0.531 1.062 .074/.121
5/8 0.688 1.750 .108/.160 0.656 1.312 .074/.121
7/8 0.938 2.250 .136/.192 0.938 1.750 .108/.160
3/4 0.812 2.000 .122/.177 0.812 1.469 .108/.160
1 1.062 2.500 .136/.192 1.062 2.000 .108/.160
1 1/4 1.375 3.000 .136/.192 1.375 2.500 .136/.192
1 1/8 1.250 2.750 .136/.192 1.250 2.250 .108/.160
1 3/8 1.500 3.250 .153/.213 1.500 2.750 .136/.213
3 3.125 5.500 .249/.327
1 5/8 1.750 3.750 .153/.213
1 1/2 1.625 3.500 .153/.213 1.625 3.000 .153/.213
1 3/4 1.875 4.000 .153/.213
2 2.125 4.500 .153/.213
1 7/8 2.000 4.250 .153/.213
2 1/2 2.625 5.000 .210/.280
2 1/4 2.375 4.750 .320/.248
2 3/4 2.875 5.250 .228/.410S
APPROX WEIGHT IN K.G. PER 1000 PIECE

Size

M10

M12

M16

M18

M20

M22

M24

M27

M30

M33

M36

M39

M42

M45

M48

M52

M56

M60

M64

M72

50

40.60

57.02

107.00

139.00

178.25

222.00

265.00

390.00

513.25

648.00

795.00

55

43.70

61.42

114.00

147.00

188.50

235.00

283.00

410.00

538.50

676.00

835.00

60

46.80

65.82

121.00

155.00

198.75

248.00

301.00

430.00

563.75

704.00

875.00

1087.00

65

49.90

70.22

128.00

163.00

209.00

261.00

319.00

450.00

589.00

732.00

915.00

1134.00

70

53.00

74.62

136.00

171.00

219.25

274.00

337.00

470.00

614.25

760.00

955.00

1181.00

1390.00

75

56.10

79.02

144.00

179.00

229.50

287.00

355.00

490.00

639.50

788.00

995.00

1228.00

1445.00

80

59.20

83.42

152.00

187.00

239.75

300.00

373.00

510.00

664.75

821.00

1035.00

1275.00

1500.00

1900.00

85

62.30

87.82

160.00

195.00

250.00

313.00

391.00

531.00

690.00

854.00

1075.00

1322.00

1555.00

1945.00

90

65.40

92.22

168.00

203.00

260.25

326.00

409.00

552.00

716.50

887.00

1115.00

1369.00

1610.00

1990.00

2220.00

95

68.50

96.62

176.00

211.00

270.50

339.00

427.00

573.00

743.00

920.00

1155.00

1416.00

1665.00

2035.00

2290.00

100

71.60

101.02

184.00

219.00

280.75

352.00

445.00

594.00

769.50

953.00

1195.00

1463.00

1720.00

2080.00

2360.00

2640.00

3400.00

110

77.80

110.00

200.00

237.00

301.25

377.00

481.00

636.00

824.75

1023.00

1250.00

1530.00

1824.00

2170.00

2500.00

2810.00

3590.00

4240.00

4910.00

120

84.00

119.00

216.00

253.00

321.75

402.00

517.00

678.00

880.00

1093.00

1330.00

1620.00

1928.00

2260.00

2640.00

2980.00

3780.00

4460.00

5160.00

6820.00

130

90.20

127.80

232.00

269.00

342.25

427.00

553.00

720.00

935.25

1163.00

1410.00

1710.00

2032.00

2350.00

2780.00

3150.00

3970.00

4680.00

5410.00

7130.00

140

96.40

136.60

248.00

285.00

362.75

452.00

589.00

762.00

990.25

1233.00

1490.00

1800.00

2136.00

2440.00

2920.00

3320.00

4160.00

4900.00

5660.00

7440.00

150

102.60

145.40

264.00

301.00

383.25

477.00

625.00

804.00

1045.75

1303.00

1570.00

1890.00

2240.00

2530.00

3060.00

3490.00

4350.00

5120.00

5910.00

7750.00

160

108.80

154.20

280.00

317.00

403.75

502.00

661.00

846.00

1101.00

1373.00

1650.00

1980.00

2344.00

2620.00

3200.00

3660.00

4540.00

5340.00

6160.00

8060.00

170

115.00

163.00

296.00

333.00

424.25

527.00

697.00

888.00

1156.25

1443.00

1730.00

2070.00

2448.00

2710.00

3340.00

3830.00

4730.00

5560.00

6410.00

8370.00

180

121.20

172.00

312.00

349.00

444.75

552.00

733.00

930.00

1211.50

1513.00

1810.00

2160.00

2552.00

2800.00

3480.00

4000.00

4920.00

5780.00

6660.00

8680.00

190

127.40

181.00

328.00

365.00

465.25

577.00

769.00

972.00

1266.75

1583.00

1890.00

2250.00

2656.00

2890.00

3620.00

4170.00

5110.00

6000.00

6910.00

8990.00

200

133.60

190.00

344.00

381.00

485.75

602.00

805.00

1014.00

1322.00

1653.00

1970.00

2340.00

2760.00

2980.00

3760.00

4340.00

5300.00

6220.00

7160.00

9300.00

210

139.80

199.00

360.00

397.00

506.25

627.00

841.00

1056.00

1377.25

1723.00

2050.00

2430.00

2864.00

3070.00

3900.00

4510.00

5490.00

6440.00

7410.00

9610.00

220

146.00

208.00

376.00

413.00

526.75

652.00

877.00

1098.00

1432.50

1793.00

2130.00

2520.00

2968.00

3160.00

4040.00

4680.00

5680.00

6660.00

7660.00

9920.00

230

152.20

217.00

392.00

429.00

547.25

677.00

913.00

1140.00

1487.75

1863.00

2210.00

2610.00

3072.00

3250.00

4180.00

4850.00

5870.00

6880.00

7910.00

10230.00

240

158.40

226.00

408.00

445.00

567.75

702.00

949.00

1182.00

1543.00

1933.00

2290.00

2700.00

3176.00

3340.00

4320.00

5020.00

6060.00

7100.00

8160.00

10540.00

250

164.60

235.00

424.00

461.00

588.25

727.00

985.00

1224.00

1598.25

2003.00

2370.00

2790.00

3280.00

3430.00

4460.00

5190.00

6250.00

7320.00

8410.00

10850.00

260

170.80

244.00

440.00

477.00

608.75

752.00

1021.00

1266.00

1653.50

2073.00

2450.00

2880.00

3384.00

3520.00

4600.00

5360.00

6440.00

7540.00

8660.00

11160.00

270

177.00

253.00

456.00

493.00

629.25

777.00

1057.00

1308.00

1708.75

2143.00

2530.00

2970.00

3488.00

3610.00

4740.00

5530.00

6630.00

7760.00

8910.00

11470.00

280

183.20

262.00

472.00

509.00

649.75

802.00

1093.00

1350.00

1764.00

2213.00

2610.00

3060.00

3592.00

3700.00

4880.00

5700.00

6820.00

7980.00

9160.00

11780.00

290

189.40

271.00

488.00

525.00

670.25

827.00

1129.00

1392.00

1819.25

2283.00

2690.00

3150.00

3696.00

3790.00

5020.00

5870.00

7010.00

8200.00

9410.00

12090.00

300

195.60

280.00

504.00

541.00

690.75

852.00

1165.00

1434.00

1874.50

2353.00

2770.00

3240.00

3800.00

3880.00

5160.00

6040.00

7200.00

8420.00

9660.00

12400.00

310

201.80

289.00

520.00

557.00

711.25

877.00

1201.00

1476.00

1929.75

2423.00

2850.00

3330.00

3904.00

3970.00

5300.00

6210.00

7390.00

8640.00

9910.00

12710.00

320

208.00

298.00

536.00

573.00

731.75

902.00

1237.00

1518.00

1985.00

2493.00

2930.00

3420.00

4008.00

4060.00

5440.00

6380.00

7580.00

8860.00

10160.00

13020.00

330

214.20

307.00

552.00

589.00

752.25

927.00

1273.00

1560.00

2040.25

2563.00

3010.00

3510.00

4112.00

4150.00

5580.00

6550.00

7770.00

9080.00

10410.00

13330.00

340

220.40

316.00

568.00

605.00

772.75

952.00

1309.00

1602.00

2095.50

2633.00

3090.00

3600.00

4216.00

4240.00

5720.00

6720.00

7960.00

9300.00

10660.00

13640.00

350

226.60

325.00

584.00

621.00

793.25

977.00

1345.00

1644.00

2150.75

2703.00

3170.00

3690.00

4320.00

4330.00

5860.00

6890.00

8150.00

9520.00

10910.00

13950.00

360

232.80

334.00

600.00

637.00

813.75

1002.00

1381.00

1686.00

2206.00

2773.00

3250.00

3780.00

4424.00

4420.00

6000.00

7060.00

8340.00

9740.00

11160.00

14260.00

370

239.00

343.00

616.00

653.00

834.25

1027.00

1417.00

1728.00

2261.25

2843.00

3330.00

3870.00

4528.00

4510.00

6140.00

7230.00

8530.00

9960.00

11410.00

14570.00

380

245.20

352.00

632.00

669.00

854.75

1052.00

1453.00

1770.00

2316.50

2913.00

3410.00

3960.00

4632.00

4600.00

6280.00

7400.00

8720.00

10180.00

11660.00

14880.00

390

251.40

361.00

648.00

685.00

875.25

1077.00

1489.00

1812.00

2371.75

2983.00

3490.00

4050.00

4736.00

4690.00

6420.00

7570.00

8910.00

10400.00

11910.00

15190.00

400

257.60

370.00

664.00

701.00

895.75

1102.00

1525.00

1854.00

2427.00

3053.00

3570.00

4140.00

4840.00

4780.00

6560.00

7740.00

9100.00

10620.00

12160.00

15500.00

Manufacturing Process of Duplex Steel Fasteners

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Duplex Steel Fasteners Application

FAQs

What are Duplex Steel Fasteners?
They are high-strength hardware components made from a specialized stainless steel alloy featuring an equal 50/50 microstructural mix of ferritic and austenitic grains, yielding double the strength of standard stainless grades.

They are commonly specified for petrochemical refineries, chemical processing plants, naval applications, offshore oil drilling, desalination plants and heavy industrial buildings where large structural loads are typical.

Yeah. Their particular chemical composition makes them resistant to chloride stress corrosion cracking, pitting and crevice attack, making them the perfect choice for prolonged saltwater and marine splash zone exposure.

We manufacture parts in a range of performance grades – from standard Duplex 2205 (UNS S32205/S31803) to the highly alloyed Super Duplex 2507 (UNS S32750) for extreme circumstances.

Yes. Exceptional resistance to organic acids, caustic solutions and highly corrosive industrial chemical process media is achieved by high chromium, nickel, molybdenum and nitrogen concentrations.

They provide a greater strength-to-weight ratio than standard carbon steels, requiring less material mass, eliminating the chance of unexpected stress cracking, and considerably extending the service life of equipment in a severe environment.

Exporter, Manufacturer & Supplier of Duplex Steel Fasteners in various material and sizes.

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