DIN 6798 Tooth Lock Washer | Serrated Marine Lock Washer
DIN 6798 Tooth Lock Washer | Serrated Marine Lock Washer
DIN 6798 Form J (Internal) / Form V (External) | M3–M24 | Carbon Steel Zinc Flakes / Dacromet / SS304 / SS316
DIN 6798 serrated tooth lock washer with multi-point angular teeth for marine engine room equipment, electrical panel fastening, and vibration-prone bolted joints. Available in internal tooth (Form J) and external tooth (Form V) configurations.
Product Overview
TheDIN 6798 Tooth Lock Washer is a serrated spring steel washer featuring multiple teeth bent at precise angles around its periphery or inner ring. When tightened between the nut face and the mating surface, each tooth bites into both surfaces, creating a positive mechanical lock that resists rotational loosening under vibration and dynamic loading.
Unlike a standard split lock washer that relies on a single split-ring spring force, the DIN 6798 tooth lock washer distributes locking engagement across multiple contact points, delivering superior anti-rotation resistance in high-vibration marine environments.
Types: Form J vs Form V
| Feature | Form J (Internal Tooth) | Form V (External Tooth) |
|---|---|---|
| Tooth Position | Teeth on inner diameter | Teeth on outer diameter |
| Visible After Assembly | Hidden under nut face | Visible around nut perimeter |
| Typical Use | Where exposed teeth are unacceptable | Where maximum bite area is needed |
| Marine Application | Electrical panels, instrumentation mounts | Engine mounts, pump bases, pipe clamps |
Technical Specifications
| Parameter | Value |
|---|---|
| Standard | DIN 6798 |
| Forms | Form J (Internal Tooth) / Form V (External Tooth) |
| Size Range | M3 – M24 |
| Material | Spring Steel C60 / C67 / C75 (Carbon Steel); Stainless Steel SS304 / SS316 |
| Hardness | 420–520 HV (Carbon Steel, hardened and tempered) |
| Surface Finish | Zinc Flakes (≥720 h salt spray per DIN EN ISO 9227) / Dacromet / Black Oxide / Plain |
| Tooth Angle Tolerance | ±3° |
| Service Temperature | −40 °C to +200 °C (Carbon Steel); up to +300 °C (SS316) |
Dimensional Data (Form J – Internal Tooth)
| Thread Size | d₁ (mm) | D (mm) | s (mm) |
|---|---|---|---|
| M3 | 3.2 | 7 | 0.5 |
| M4 | 4.3 | 9 | 0.5 |
| M5 | 5.3 | 10 | 0.5 |
| M6 | 6.4 | 12 | 0.8 |
| M8 | 8.4 | 16 | 0.8 |
| M10 | 10.5 | 20 | 1.0 |
| M12 | 13.0 | 24 | 1.0 |
| M16 | 17.0 | 30 | 1.2 |
| M20 | 21.0 | 37 | 1.5 |
| M24 | 25.0 | 44 | 1.5 |
Note: Dimensions are representative per DIN 6798. For Form V (External Tooth), outer diameter D is larger than Form J for the same thread size. Contact us for complete dimensional tables.
Marine Applications
- Engine Room: Generator base plates, pump motor housings, compressor mounts, fuel system brackets
- Electrical Systems: Distribution panel mounting, cable tray fasteners, instrumentation junction boxes
- Deck Equipment: Winch base bolts, cleat fasteners, railing post anchors subject to vibration
- Piping Systems: Pipe clamp bolts, hanger rod connections where dynamic loads cause nut rotation
Material & Finish Selection Guide
| Environment | Recommended Material | Recommended Finish |
|---|---|---|
| Indoor / Dry compartments | Carbon Steel C60/C67 | Zinc Flakes or Black Oxide |
| Engine Room (moderate corrosion) | Carbon Steel C60/C67 | Dacromet (≥720 h SST) |
| Deck / Exposed to seawater | SS316 | Plain (passivated) |
| Electrical panel (non-magnetic) | SS304 | Plain |
Installation Notes
- Ensure mating surfaces are clean and free of oil or corrosion before assembly.
- Place the tooth lock washer directly under the nut face (Form J) or over the bolt head perimeter (Form V).
- Tighten to the specified torque. The teeth will bite into both the nut face and the work surface, creating the mechanical lock.
- Do not reuse DIN 6798 washers after removal — tooth deformation reduces locking effectiveness on re-installation.
- For critical vibration applications, combine with a secondary locking method (e.g., prevailing torque nut or safety wire).
Why Choose SINOFASTENER
- Manufactured per DIN 6798 with tooth angle tolerance ±3° for consistent locking performance
- Full size range M3–M24 in Form J and Form V, available from stock
- Carbon steel, SS304, and SS316 materials with mill certificates traceable to batch
- Dacromet and zinc flake coatings tested per DIN EN ISO 9227 salt spray standard
- Annual production capacity 50,000 tons across all fastener categories
- Material certificates and inspection reports provided with every shipment
FAQ
What is the difference between DIN 6798 Form J and Form V?
Form J (internal tooth) has teeth on the inner diameter, hidden under the nut face after assembly. Form V (external tooth) has teeth on the outer diameter, remaining visible. Choose Form J when exposed teeth are a concern (e.g., electrical panels); choose Form V when maximum locking bite area is required.
Can DIN 6798 tooth lock washers replace split lock washers?
In most vibration-prone applications, yes. DIN 6798 washers provide multi-point locking engagement, which is more effective than the single-point spring force of a split lock washer. However, for high-preload structural bolting (e.g., preloaded flange joints per EN 14399), hardened flat washers are required instead.
What material is best for seawater exposure?
SS316 is recommended for direct seawater or splash zone applications. For engine room use where corrosion is moderate, carbon steel with Dacromet coating provides sufficient protection at lower cost.
Should DIN 6798 washers be reused after removal?
No. The teeth deform during initial installation to create the locking bite. Reusing a deformed washer significantly reduces locking effectiveness. Always replace with new washers during reassembly.
What is the difference between DIN 6798 and DIN 25201?
DIN 6798 covers tooth lock washers (serrated washers), while DIN 25201 covers Nord-Lock-style wedge locking washers. They use completely different locking principles — DIN 6798 uses tooth bite engagement; DIN 25201 uses cam-action wedge locking. They are not interchangeable.
Contact Us
For DIN 6798 tooth lock washer inquiries, please contact:
E-mail:sales@sinofastener.com
SINOFASTENER — Marine Fastener Supplier | Annual Capacity 50,000 Tons
