DIN 93
Tab Washers
Manufacturer Mumbai
What Is a DIN 93 Tab Washer
Most nut-locking methods rely on friction — a spring washer’s flex, a nylon insert’s grip, a prevailing-torque thread — to resist loosening under vibration. A DIN 93 tab washer works differently: it locks purely by physical obstruction. The washer body sits under the nut as normal, but it has one or two small tabs projecting past its outer diameter. After the nut is torqued to the correct value, those tabs are bent over by hand or with pliers — one flat against a face of the hex nut, and, where a second tab is present, the other against a fixed edge or flat on the component itself.
Once bent, the nut simply cannot rotate without shearing the tab, which makes this one of the most positive and easily verified locking methods available — a quick visual check confirms whether the tab is still bent over or has been disturbed. The trade-off is that it’s a one-time locking action: once bent, the tab typically shouldn’t be reused after removal, and a fresh washer is fitted at reassembly.
Akbar Fasteners Pvt. Ltd. manufactures DIN 93 tab washers in-house at our Mumbai facility, under ISO 9001:2015, with full mill test documentation, and exports this range to over 50 countries.
Where DIN 93 Washers Genuinely Earn Their Place
Positive Mechanical Lock
The bent tab physically blocks rotation rather than relying on friction alone, giving a locking method that doesn’t degrade with vibration cycles.
Visually Verifiable at a Glance
A bent-over tab is easy to inspect during routine maintenance — you can confirm the lock is intact without special tools or torque checks.
Full Size & Weight Reference
A published dimension and weight chart lets you plan quantity and freight before an order is placed, not after.
Simple, Field-Serviceable Installation
Bent by hand or with basic pliers — no special tools required, and easily replaced with a fresh washer at every disassembly.
DIN 93 Tab Washer Dimension & Weight Chart
Standard nominal dimensions and approximate weight by thread size — inner diameter (d1), outer diameter of the washer body (d2), and thickness (s) are the figures to check first against the nut and bolt hole clearance. Weight is given per 100 pieces; actual weight may vary slightly with material and tab length selected.
| Thread Size (d) | Inner Dia. (d1) | Outer Dia. (d2) | Thickness (s) | Tab Length | Approx Weight/100pcs |
|---|---|---|---|---|---|
| M4 | 4.3 mm | 11.0 mm | 0.5 mm | 6 mm | ~0.28 kg |
| M5 | 5.3 mm | 13.0 mm | 0.5 mm | 7 mm | ~0.40 kg |
| M6 | 6.4 mm | 15.5 mm | 0.6 mm | 8 mm | ~0.62 kg |
| M8 | 8.4 mm | 19.5 mm | 0.8 mm | 10 mm | ~1.15 kg |
| M10 | 10.5 mm | 24.0 mm | 1.0 mm | 12 mm | ~1.95 kg |
| M12 | 13.0 mm | 28.0 mm | 1.2 mm | 14 mm | ~2.85 kg |
| M16 | 17.0 mm | 34.0 mm | 1.5 mm | 18 mm | ~4.40 kg |
| M20 | 21.0 mm | 42.0 mm | 2.0 mm | 22 mm | ~7.60 kg |
| M24 | 25.0 mm | 50.0 mm | 2.5 mm | 28 mm | ~11.90 kg |
Figures shown are representative reference values in steel for quick planning purposes and may vary slightly by manufacturer tolerance and tab configuration selected. Please confirm exact dimensions against the current DIN 93 standard document or your engineering drawing, and request our certified dimensional data sheet, before finalizing a purchase order.
Locking Washer Product Range
Tab Washers
Bendable single and double tab locking washers in carbon and stainless steel, M4 to M36.
DIN 128Spring Lock Washers
Curved spring washers providing friction-based resistance to nut loosening under load.
DIN 6798Toothed Lock Washers
Internal or external tooth washers biting into the mating surface for added locking friction.
DIN 125Flat Washers
Standard flat washers for load distribution, supplied to complement any locking washer assembly.
DIN 93 Technical Overview
Available Materials
- Spring Steel Standard Offering
- Stainless Steel A2 / A4 on Request
- Mild Steel Lower Load Applications
- Surface Finish Zinc Plated / Bright
- Custom Material To Specification
Design Variants
- Single Tab Nut Face Only
- Double Tab Nut Face + Component Edge
- Bend Method Hand / Pliers, Field Serviceable
- Reusability Single-Use per Bend
- Testing MTC / NABL on Request
Available Dimensions
- Thread Size M4 – M36
- Thickness 0.5 – 2.5 mm
- Custom Sizes To Drawing
- Standard Reference DIN 93
- Packaging Loose / Boxed / Bulk
Application Areas
Wherever a nut must be visibly, verifiably locked against vibration.
Agricultural Machinery
equipment fastening
General Industrial Machinery
and conveyor systems
Rail & Transport Equipment
needing verifiable locking
Pumps & Rotating Equipment
fastening under vibration
Construction Equipment
assembly and maintenance
Marine & Deck Equipment
visual maintenance checks
Power Transmission Equipment
fastener retention
General Fabrication & Assembly
is preferred over friction
Standard Export Documentation
Prepared as standard practice for every tab washer shipment.
Mill Test Certificate (MTC)
Material composition and hardness verification for every production batch.
Certificate of Conformance
Confirms the shipment matches the purchase order specification, size, and grade in full.
Certificate of Origin (COO)
Confirms India as country of manufacture for destination customs purposes.
Commercial Invoice & Packing List
Itemized value, Incoterm, and detailed carton/weight breakdown for customs clearance.
Dimensional Data Sheet
Certified inner/outer diameter and thickness data against DIN 93 available on request before order confirmation.
Bill of Lading
Ocean or air freight shipping document confirming carrier, mode, and consignee details.
Internationally Recognised Standards Coverage
Related Fastener Grades & Standards
DIN 84 Cheese Head Screws
Slotted machine screws for general electrical and light assembly fastening.
View DIN 84 →DIN 261 T-Head Bolts
T-slot clamping bolts for machine tool tables, with a matching standard dimension and weight chart.
View DIN 261 →Stainless Steel 316 Fasteners
Corrosion-resistant option for tab washers and general fastening in washdown or humid environments.
View SS 316 →Top Nickel Fasteners Manufacturer
See our full in-house nickel alloy manufacturing and documentation capability.
View Manufacturer Page →Send Us Your
Size, Tab Style & Quantity
Tell us your thread size, single or double tab requirement, and material preference — we’ll confirm the correct DIN 93 specification and issue a certified dimensional data sheet with your quote. Akbar Fasteners Pvt. Ltd. responds within 24 hours.
Sales: +91 724 0000 733 · Support: +91 800 9315 333 · sales@akbarfasteners.in