DIN Fasteners
Manufacturer
India · Mumbai
Mumbai’s Exotic Alloy DIN Fastener Specialist Since 1998
Akbar Fasteners Pvt. Ltd. manufactures DIN-standard exotic alloy fasteners from our ISO 9001:2015 certified Mumbai facility. The DIN (Deutsches Institut für Normung) metric fastener standards — DIN 931, DIN 933, DIN 934, DIN 975, DIN 125, DIN 127, DIN 912, and DIN 6334 — have become the dominant global standard for metric fasteners in chemical, petrochemical, pharmaceutical, and industrial equipment, progressively superseded by the ISO metric series (ISO 4014, ISO 4017, ISO 4032, etc.) but still widely specified in European engineering drawings, plant documentation, and legacy equipment.
Akbar Fasteners manufactures to both DIN and ISO designations from the same certified exotic alloy bar stock — DIN 931 and ISO 4014 (partial thread hex bolt), DIN 933 and ISO 4017 (full thread hex bolt), DIN 934 and ISO 4032 (standard hex nut) are dimensionally identical with only minor thread tolerance class differences that do not affect exotic alloy fastener procurement. We accept DIN, ISO, and DIN/ISO dual-standard specifications and supply with complete MTC, PMI XRF, COC, and NABL test report documentation.
For European EPC projects, German chemical plant operators, and global facilities using DIN-based engineering drawings, Akbar Fasteners provides the complete DIN exotic alloy fastener package in Hastelloy, Monel, Inconel, Duplex, Super Duplex, Alloy 20, and Titanium from a single ISO 9001:2015 certified Mumbai source.
DIN and ISO — Both Accepted
We accept DIN and ISO designations interchangeably. DIN 931 = ISO 4014 (partial thread), DIN 933 = ISO 4017 (full thread), DIN 934 = ISO 4032 (hex nut). Same certified alloy bar stock, same NABL test reports.
M6–M100 Full Range
DIN standard metric thread M6 through M100 in all exotic alloys. Standard stock M6–M48 in the most common alloys; M52–M100 and fine pitch on order with NABL test reports.
European EPC Project Experience
Regular supply to German, Dutch, Belgian, and Scandinavian chemical plant EPC contractors and operators. DIN documentation format, metric units, heat traceability per European EN standards on request.
Matched Heat — Complete DIN Assembly
DIN 931/933 hex bolts + DIN 934 hex nuts + DIN 125 washers from the same certified exotic alloy heat — one MTC, one PMI report, one COC for the complete DIN fastener assembly.
DIN Fastener Standards Coverage
Akbar Fasteners Pvt. Ltd. manufactures to ten DIN fastener standards in the complete exotic alloy range. Each DIN standard is dimensionally equivalent to the corresponding ISO standard — both accepted on any order.
DIN 931
Hex bolt with unthreaded plain shank — the standard DIN partial thread hex bolt in exotic alloys for structural connections, equipment skid bases, and mechanical joints where shear capacity must be combined with corrosion resistance. The plain shank spans the joint and carries shear; thread at the end engages the nut. M6–M100.
DIN 933
Hex bolt with thread running the complete length — the most common DIN exotic alloy bolt for chemical equipment covers, reactor body connections, agitated vessel bolting, and all flanged or gasketed connections where full thread engagement is required. M6–M100. Most common exotic alloy DIN bolt form.
DIN 934
Standard-height hex nut — the DIN standard nut for exotic alloy hex bolt assemblies in chemical equipment cover bolting, structural connections, and all applications where ASME B18.2.2 heavy hex is not specified. M6–M100. Supplied from the same certified exotic alloy heat as matching DIN 931/933 bolts.
DIN 975
Full-thread metric rod — continuous thread along the complete length, cut to any required length. Used for hanger systems in corrosive chemical plant, tie-rod structural connections, equipment support systems in reducing acid and seawater environments, and replacement of failed carbon steel threaded rod in exotic alloy applications. M6–M100, lengths to 3,000mm.
DIN 976
End-threaded rod — unthreaded shank with threaded sections at each end. Used where a specific thread length at each end is required and the central shank carries tensile load or occupies a specific clearance zone. Lengths to 3,000mm. Available in all exotic alloys from same certified heat as matching DIN 931/934 bolt-nut assemblies.
DIN 125
Standard flat washer in Series A (tight ID for centering) and Series B (clearance ID). Distributes bolt bearing load and provides a matched-alloy contact surface under the nut in corrosive service. M5–M100. Supplied from the same certified exotic alloy heat as DIN 931/933 bolts — zero galvanic potential at the washer-nut bearing interface.
DIN 127
Split-ring helical spring washer — maintains bolt preload against vibration, thermal cycling, and dynamic loading in chemical plant equipment with pump-induced pulsation, agitator vibration, and rotating machinery. M5–M64. Available in exotic alloys for matched-alloy spring washer under DIN 934 nuts in reducing acid and seawater service.
DIN 912
Hex socket cylindrical head screw for confined-access bolting — chemical reactor internals, agitator baffle attachment, heat exchanger internal baffles, instrument flange connections, and seawater pump internals where standard hex head clearance is unavailable. Allen key drive. M4–M36 in all exotic alloys from same ASTM certified bar.
DIN 6334
Long hex coupling nut — length approximately 3× the hex width. Used for joining two sections of DIN 975/976 threaded rod, extending stud bolt engagement depth, and structural tie-rod assemblies in corrosive environments. M6–M100 in exotic alloys. Matched from same certified heat as threaded rod for zero galvanic couple in the rod-nut joint.
DIN 6921
Hex bolt with integrated plain or serrated flange (washer face) under the head — distributes bearing load without a separate washer and eliminates the washer-flange face crevice. Used in FRP-lined vessel nozzle connections, rubber-lined equipment covers, and composite substrate connections in corrosive chemical plant. M6–M64.
DIN 9021
Large outer diameter (fender) washer — OD significantly larger than DIN 125 for distributing bolt load over a greater bearing area through soft substrates. Used with exotic alloy bolts in FRP-lined chemical plant connections, composite equipment covers, and acid-resistant polymer structural connections. M6–M64.
DIN 938 / 939
Double-end studs (DIN 938 short-end, DIN 939 long-end) for tapped-bore equipment connections — one end engages the equipment tapped hole, the other end takes the DIN 934 nut. For European chemical plant where ASME B16.5 is not specified. Used in DIN-flanged chemical process equipment across HCl plant, acid process, and reducing acid environments. M12–M100.
DIN to ISO Fastener Standard Cross-Reference
DIN standards were progressively replaced by ISO metric standards from the 1990s onward. Many engineering drawings still reference DIN numbers. This table shows the direct equivalents — Akbar Fasteners accepts orders under either designation.
| DIN Standard | ISO Equivalent | Fastener Type | Size Range | Exotic Alloys Available |
|---|---|---|---|---|
| BOLTS — HEX HEAD · EXOTIC ALLOY · ASTM B574 · B335 · B865 · B164 CERTIFIED BAR | ||||
| DIN 931 | ISO 4014 | Hex Bolt — Partial Thread | M6–M100 | C276 · C22 · B3 · B2 · K500 · M400 · Alloys |
| DIN 933 | ISO 4017 | Hex Bolt — Full Thread | M6–M100 | C276 · C22 · B3 · B2 · K500 · M400 · Alloys |
| DIN 6921 | ISO 4162 | Flanged Hex Bolt | M6–M64 | C276 · C22 · B3 · K500 · Duplex |
| NUTS — HEX · EXOTIC ALLOY | ||||
| DIN 934 | ISO 4032 | Standard Hex Nut | M6–M100 | C276 · C22 · B3 · B2 · K500 · M400 · Alloys |
| DIN 6334 | ISO 8733 | Coupling Nut (Long Hex) | M6–M100 | C276 · B3 · B2 · K500 · M400 |
| DIN 6923 | ISO 4161 | Flanged Hex Nut | M6–M64 | C276 · C22 · K500 · Duplex |
| WASHERS — EXOTIC ALLOY | ||||
| DIN 125 A/B | ISO 7089/7090 | Plain Flat Washer | M5–M100 | C276 · C22 · B3 · B2 · K500 · M400 · Alloys |
| DIN 127 | ISO 7089 (B) | Spring Helical Washer | M5–M64 | C276 · B3 · B2 · K500 · M400 |
| DIN 9021 | ISO 7093 | Large OD Washer | M6–M64 | C276 · B3 · K500 · Duplex |
| THREADED RODS & SOCKET SCREWS — EXOTIC ALLOY | ||||
| DIN 975 | ISO 888 | Full Thread Rod (3m lengths) | M6–M100 | C276 · C22 · B3 · B2 · K500 · M400 |
| DIN 976 | — | End Thread Rod | M6–M100 | C276 · B3 · K500 · M400 |
| DIN 912 | ISO 4762 | Socket Cap Screw | M4–M36 | C276 · C22 · B3 · K500 · M400 |
| DIN 938/939 | — | Double-End Stud | M12–M100 | C276 · B3 · B2 · K500 |
Both DIN and ISO designations accepted. Fine pitch, custom lengths — sales@akbarfasteners.in
Exotic Alloys Available in DIN Fastener Standards
All alloys from certified UNS-designated mill bar stock. Click any alloy card for the product-specific page with composition data, dimension tables, and standards information.
Hastelloy C276
Hastelloy C22
Hastelloy B3
Hastelloy B2
Monel K500
Monel 400
C276 DIN 125 Washers
C276 DIN 975 Threaded Rods
Hastelloy C4 / C-2000 / G-30
Inconel 625
Duplex 2205 / Super Duplex 2507
Titanium Grade 2 / Grade 5
DIN Fastener Applications
DIN-standard exotic alloy fasteners for European-designed process equipment, German engineering procurement, and global facilities using DIN metric dimensional standards.
European Chemical Plant
German EPC procurement
Oil & Gas
corrosive service hex bolts
Offshore Platforms
Monel / Duplex hex bolts
FGD Systems
Hastelloy C22 C276 bolts
Power Generation
seawater circuit threaded rods
Desalination
brine circuit hex bolt sets
Pharmaceutical
exotic alloy DIN assemblies
HCl & Acid Plants
DIN 975 threaded rods
Complete Documentation Package
Heat & Lot Traceable
Conformance
100% Lots Verified
Tensile · Hardness
TÜV · BV · Lloyds
Need Exotic Alloy
DIN Fasteners Now?
DIN standard · alloy · size · length · quantity · documentation. Akbar Fasteners Pvt. Ltd. responds within 24 hours with full pricing, lead time, and MTC documentation list.
Export: +91 8696 32 4646 · Support: +91 800 9315 333 · export@akbarfasteners.in